rocksdb/db/version_set.cc
Huisheng Liu 904a60ff63 return timestamp from get (#6409)
Summary:
Added new Get() methods that return timestamp. Dummy implementation is given so that classes derived from DB don't need to be touched to provide their implementation. MultiGet is not included.

ReadRandom perf test (10 minutes) on the same development machine ram drive with the same DB data shows no regression (within marge of error). The test is adapted from https://github.com/facebook/rocksdb/wiki/RocksDB-In-Memory-Workload-Performance-Benchmarks.
    base line (commit 72ee067b9):
        101.712 micros/op 314602 ops/sec;   36.0 MB/s (5658999 of 5658999 found)
    This PR:
        100.288 micros/op 319071 ops/sec;   36.5 MB/s (5674999 of 5674999 found)

./db_bench --db=r:\rocksdb.github --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --cache_size=2147483648 --cache_numshardbits=6 --compression_type=none --compression_ratio=1 --min_level_to_compress=-1 --disable_seek_compaction=1 --hard_rate_limit=2 --write_buffer_size=134217728 --max_write_buffer_number=2 --level0_file_num_compaction_trigger=8 --target_file_size_base=134217728 --max_bytes_for_level_base=1073741824 --disable_wal=0 --wal_dir=r:\rocksdb.github\WAL_LOG --sync=0 --verify_checksum=1 --delete_obsolete_files_period_micros=314572800 --max_background_compactions=4 --max_background_flushes=0 --level0_slowdown_writes_trigger=16 --level0_stop_writes_trigger=24 --statistics=0 --stats_per_interval=0 --stats_interval=1048576 --histogram=0 --use_plain_table=1 --open_files=-1 --mmap_read=1 --mmap_write=0 --memtablerep=prefix_hash --bloom_bits=10 --bloom_locality=1 --duration=600 --benchmarks=readrandom --use_existing_db=1 --num=25000000 --threads=32
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6409

Differential Revision: D20200086

Pulled By: riversand963

fbshipit-source-id: 490edd74d924f62bd8ae9c29c2a6bbbb8410ca50
2020-03-02 16:01:00 -08:00

6006 lines
220 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include "db/version_set.h"
#include <stdio.h>
#include <algorithm>
#include <array>
#include <cinttypes>
#include <list>
#include <map>
#include <set>
#include <string>
#include <unordered_map>
#include <vector>
#include "compaction/compaction.h"
#include "db/internal_stats.h"
#include "db/log_reader.h"
#include "db/log_writer.h"
#include "db/memtable.h"
#include "db/merge_context.h"
#include "db/merge_helper.h"
#include "db/pinned_iterators_manager.h"
#include "db/table_cache.h"
#include "db/version_builder.h"
#include "file/filename.h"
#include "file/random_access_file_reader.h"
#include "file/read_write_util.h"
#include "file/writable_file_writer.h"
#include "monitoring/file_read_sample.h"
#include "monitoring/perf_context_imp.h"
#include "monitoring/persistent_stats_history.h"
#include "rocksdb/env.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/write_buffer_manager.h"
#include "table/format.h"
#include "table/get_context.h"
#include "table/internal_iterator.h"
#include "table/merging_iterator.h"
#include "table/meta_blocks.h"
#include "table/multiget_context.h"
#include "table/plain/plain_table_factory.h"
#include "table/table_reader.h"
#include "table/two_level_iterator.h"
#include "test_util/sync_point.h"
#include "util/coding.h"
#include "util/stop_watch.h"
#include "util/string_util.h"
#include "util/user_comparator_wrapper.h"
namespace ROCKSDB_NAMESPACE {
namespace {
// Find File in LevelFilesBrief data structure
// Within an index range defined by left and right
int FindFileInRange(const InternalKeyComparator& icmp,
const LevelFilesBrief& file_level,
const Slice& key,
uint32_t left,
uint32_t right) {
auto cmp = [&](const FdWithKeyRange& f, const Slice& k) -> bool {
return icmp.InternalKeyComparator::Compare(f.largest_key, k) < 0;
};
const auto &b = file_level.files;
return static_cast<int>(std::lower_bound(b + left,
b + right, key, cmp) - b);
}
Status OverlapWithIterator(const Comparator* ucmp,
const Slice& smallest_user_key,
const Slice& largest_user_key,
InternalIterator* iter,
bool* overlap) {
InternalKey range_start(smallest_user_key, kMaxSequenceNumber,
kValueTypeForSeek);
iter->Seek(range_start.Encode());
if (!iter->status().ok()) {
return iter->status();
}
*overlap = false;
if (iter->Valid()) {
ParsedInternalKey seek_result;
if (!ParseInternalKey(iter->key(), &seek_result)) {
return Status::Corruption("DB have corrupted keys");
}
if (ucmp->CompareWithoutTimestamp(seek_result.user_key, largest_user_key) <=
0) {
*overlap = true;
}
}
return iter->status();
}
// Class to help choose the next file to search for the particular key.
// Searches and returns files level by level.
// We can search level-by-level since entries never hop across
// levels. Therefore we are guaranteed that if we find data
// in a smaller level, later levels are irrelevant (unless we
// are MergeInProgress).
class FilePicker {
public:
FilePicker(std::vector<FileMetaData*>* files, const Slice& user_key,
const Slice& ikey, autovector<LevelFilesBrief>* file_levels,
unsigned int num_levels, FileIndexer* file_indexer,
const Comparator* user_comparator,
const InternalKeyComparator* internal_comparator)
: num_levels_(num_levels),
curr_level_(static_cast<unsigned int>(-1)),
returned_file_level_(static_cast<unsigned int>(-1)),
hit_file_level_(static_cast<unsigned int>(-1)),
search_left_bound_(0),
search_right_bound_(FileIndexer::kLevelMaxIndex),
#ifndef NDEBUG
files_(files),
#endif
level_files_brief_(file_levels),
is_hit_file_last_in_level_(false),
curr_file_level_(nullptr),
user_key_(user_key),
ikey_(ikey),
file_indexer_(file_indexer),
user_comparator_(user_comparator),
internal_comparator_(internal_comparator) {
#ifdef NDEBUG
(void)files;
#endif
// Setup member variables to search first level.
search_ended_ = !PrepareNextLevel();
if (!search_ended_) {
// Prefetch Level 0 table data to avoid cache miss if possible.
for (unsigned int i = 0; i < (*level_files_brief_)[0].num_files; ++i) {
auto* r = (*level_files_brief_)[0].files[i].fd.table_reader;
if (r) {
r->Prepare(ikey);
}
}
}
}
int GetCurrentLevel() const { return curr_level_; }
FdWithKeyRange* GetNextFile() {
while (!search_ended_) { // Loops over different levels.
while (curr_index_in_curr_level_ < curr_file_level_->num_files) {
// Loops over all files in current level.
FdWithKeyRange* f = &curr_file_level_->files[curr_index_in_curr_level_];
hit_file_level_ = curr_level_;
is_hit_file_last_in_level_ =
curr_index_in_curr_level_ == curr_file_level_->num_files - 1;
int cmp_largest = -1;
// Do key range filtering of files or/and fractional cascading if:
// (1) not all the files are in level 0, or
// (2) there are more than 3 current level files
// If there are only 3 or less current level files in the system, we skip
// the key range filtering. In this case, more likely, the system is
// highly tuned to minimize number of tables queried by each query,
// so it is unlikely that key range filtering is more efficient than
// querying the files.
if (num_levels_ > 1 || curr_file_level_->num_files > 3) {
// Check if key is within a file's range. If search left bound and
// right bound point to the same find, we are sure key falls in
// range.
assert(curr_level_ == 0 ||
curr_index_in_curr_level_ == start_index_in_curr_level_ ||
user_comparator_->CompareWithoutTimestamp(
user_key_, ExtractUserKey(f->smallest_key)) <= 0);
int cmp_smallest = user_comparator_->CompareWithoutTimestamp(
user_key_, ExtractUserKey(f->smallest_key));
if (cmp_smallest >= 0) {
cmp_largest = user_comparator_->CompareWithoutTimestamp(
user_key_, ExtractUserKey(f->largest_key));
}
// Setup file search bound for the next level based on the
// comparison results
if (curr_level_ > 0) {
file_indexer_->GetNextLevelIndex(curr_level_,
curr_index_in_curr_level_,
cmp_smallest, cmp_largest,
&search_left_bound_,
&search_right_bound_);
}
// Key falls out of current file's range
if (cmp_smallest < 0 || cmp_largest > 0) {
if (curr_level_ == 0) {
++curr_index_in_curr_level_;
continue;
} else {
// Search next level.
break;
}
}
}
#ifndef NDEBUG
// Sanity check to make sure that the files are correctly sorted
if (prev_file_) {
if (curr_level_ != 0) {
int comp_sign = internal_comparator_->Compare(
prev_file_->largest_key, f->smallest_key);
assert(comp_sign < 0);
} else {
// level == 0, the current file cannot be newer than the previous
// one. Use compressed data structure, has no attribute seqNo
assert(curr_index_in_curr_level_ > 0);
assert(!NewestFirstBySeqNo(files_[0][curr_index_in_curr_level_],
files_[0][curr_index_in_curr_level_-1]));
}
}
prev_file_ = f;
#endif
returned_file_level_ = curr_level_;
if (curr_level_ > 0 && cmp_largest < 0) {
// No more files to search in this level.
search_ended_ = !PrepareNextLevel();
} else {
++curr_index_in_curr_level_;
}
return f;
}
// Start searching next level.
search_ended_ = !PrepareNextLevel();
}
// Search ended.
return nullptr;
}
// getter for current file level
// for GET_HIT_L0, GET_HIT_L1 & GET_HIT_L2_AND_UP counts
unsigned int GetHitFileLevel() { return hit_file_level_; }
// Returns true if the most recent "hit file" (i.e., one returned by
// GetNextFile()) is at the last index in its level.
bool IsHitFileLastInLevel() { return is_hit_file_last_in_level_; }
private:
unsigned int num_levels_;
unsigned int curr_level_;
unsigned int returned_file_level_;
unsigned int hit_file_level_;
int32_t search_left_bound_;
int32_t search_right_bound_;
#ifndef NDEBUG
std::vector<FileMetaData*>* files_;
#endif
autovector<LevelFilesBrief>* level_files_brief_;
bool search_ended_;
bool is_hit_file_last_in_level_;
LevelFilesBrief* curr_file_level_;
unsigned int curr_index_in_curr_level_;
unsigned int start_index_in_curr_level_;
Slice user_key_;
Slice ikey_;
FileIndexer* file_indexer_;
const Comparator* user_comparator_;
const InternalKeyComparator* internal_comparator_;
#ifndef NDEBUG
FdWithKeyRange* prev_file_;
#endif
// Setup local variables to search next level.
// Returns false if there are no more levels to search.
bool PrepareNextLevel() {
curr_level_++;
while (curr_level_ < num_levels_) {
curr_file_level_ = &(*level_files_brief_)[curr_level_];
if (curr_file_level_->num_files == 0) {
// When current level is empty, the search bound generated from upper
// level must be [0, -1] or [0, FileIndexer::kLevelMaxIndex] if it is
// also empty.
assert(search_left_bound_ == 0);
assert(search_right_bound_ == -1 ||
search_right_bound_ == FileIndexer::kLevelMaxIndex);
// Since current level is empty, it will need to search all files in
// the next level
search_left_bound_ = 0;
search_right_bound_ = FileIndexer::kLevelMaxIndex;
curr_level_++;
continue;
}
// Some files may overlap each other. We find
// all files that overlap user_key and process them in order from
// newest to oldest. In the context of merge-operator, this can occur at
// any level. Otherwise, it only occurs at Level-0 (since Put/Deletes
// are always compacted into a single entry).
int32_t start_index;
if (curr_level_ == 0) {
// On Level-0, we read through all files to check for overlap.
start_index = 0;
} else {
// On Level-n (n>=1), files are sorted. Binary search to find the
// earliest file whose largest key >= ikey. Search left bound and
// right bound are used to narrow the range.
if (search_left_bound_ <= search_right_bound_) {
if (search_right_bound_ == FileIndexer::kLevelMaxIndex) {
search_right_bound_ =
static_cast<int32_t>(curr_file_level_->num_files) - 1;
}
// `search_right_bound_` is an inclusive upper-bound, but since it was
// determined based on user key, it is still possible the lookup key
// falls to the right of `search_right_bound_`'s corresponding file.
// So, pass a limit one higher, which allows us to detect this case.
start_index =
FindFileInRange(*internal_comparator_, *curr_file_level_, ikey_,
static_cast<uint32_t>(search_left_bound_),
static_cast<uint32_t>(search_right_bound_) + 1);
if (start_index == search_right_bound_ + 1) {
// `ikey_` comes after `search_right_bound_`. The lookup key does
// not exist on this level, so let's skip this level and do a full
// binary search on the next level.
search_left_bound_ = 0;
search_right_bound_ = FileIndexer::kLevelMaxIndex;
curr_level_++;
continue;
}
} else {
// search_left_bound > search_right_bound, key does not exist in
// this level. Since no comparison is done in this level, it will
// need to search all files in the next level.
search_left_bound_ = 0;
search_right_bound_ = FileIndexer::kLevelMaxIndex;
curr_level_++;
continue;
}
}
start_index_in_curr_level_ = start_index;
curr_index_in_curr_level_ = start_index;
#ifndef NDEBUG
prev_file_ = nullptr;
#endif
return true;
}
// curr_level_ = num_levels_. So, no more levels to search.
return false;
}
};
class FilePickerMultiGet {
private:
struct FilePickerContext;
public:
FilePickerMultiGet(MultiGetRange* range,
autovector<LevelFilesBrief>* file_levels,
unsigned int num_levels, FileIndexer* file_indexer,
const Comparator* user_comparator,
const InternalKeyComparator* internal_comparator)
: num_levels_(num_levels),
curr_level_(static_cast<unsigned int>(-1)),
returned_file_level_(static_cast<unsigned int>(-1)),
hit_file_level_(static_cast<unsigned int>(-1)),
range_(range),
batch_iter_(range->begin()),
batch_iter_prev_(range->begin()),
maybe_repeat_key_(false),
current_level_range_(*range, range->begin(), range->end()),
current_file_range_(*range, range->begin(), range->end()),
level_files_brief_(file_levels),
is_hit_file_last_in_level_(false),
curr_file_level_(nullptr),
file_indexer_(file_indexer),
user_comparator_(user_comparator),
internal_comparator_(internal_comparator) {
for (auto iter = range_->begin(); iter != range_->end(); ++iter) {
fp_ctx_array_[iter.index()] =
FilePickerContext(0, FileIndexer::kLevelMaxIndex);
}
// Setup member variables to search first level.
search_ended_ = !PrepareNextLevel();
if (!search_ended_) {
// REVISIT
// Prefetch Level 0 table data to avoid cache miss if possible.
// As of now, only PlainTableReader and CuckooTableReader do any
// prefetching. This may not be necessary anymore once we implement
// batching in those table readers
for (unsigned int i = 0; i < (*level_files_brief_)[0].num_files; ++i) {
auto* r = (*level_files_brief_)[0].files[i].fd.table_reader;
if (r) {
for (auto iter = range_->begin(); iter != range_->end(); ++iter) {
r->Prepare(iter->ikey);
}
}
}
}
}
int GetCurrentLevel() const { return curr_level_; }
// Iterates through files in the current level until it finds a file that
// contains atleast one key from the MultiGet batch
bool GetNextFileInLevelWithKeys(MultiGetRange* next_file_range,
size_t* file_index, FdWithKeyRange** fd,
bool* is_last_key_in_file) {
size_t curr_file_index = *file_index;
FdWithKeyRange* f = nullptr;
bool file_hit = false;
int cmp_largest = -1;
if (curr_file_index >= curr_file_level_->num_files) {
// In the unlikely case the next key is a duplicate of the current key,
// and the current key is the last in the level and the internal key
// was not found, we need to skip lookup for the remaining keys and
// reset the search bounds
if (batch_iter_ != current_level_range_.end()) {
++batch_iter_;
for (; batch_iter_ != current_level_range_.end(); ++batch_iter_) {
struct FilePickerContext& fp_ctx = fp_ctx_array_[batch_iter_.index()];
fp_ctx.search_left_bound = 0;
fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex;
}
}
return false;
}
// Loops over keys in the MultiGet batch until it finds a file with
// atleast one of the keys. Then it keeps moving forward until the
// last key in the batch that falls in that file
while (batch_iter_ != current_level_range_.end() &&
(fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level ==
curr_file_index ||
!file_hit)) {
struct FilePickerContext& fp_ctx = fp_ctx_array_[batch_iter_.index()];
f = &curr_file_level_->files[fp_ctx.curr_index_in_curr_level];
Slice& user_key = batch_iter_->ukey;
// Do key range filtering of files or/and fractional cascading if:
// (1) not all the files are in level 0, or
// (2) there are more than 3 current level files
// If there are only 3 or less current level files in the system, we
// skip the key range filtering. In this case, more likely, the system
// is highly tuned to minimize number of tables queried by each query,
// so it is unlikely that key range filtering is more efficient than
// querying the files.
if (num_levels_ > 1 || curr_file_level_->num_files > 3) {
// Check if key is within a file's range. If search left bound and
// right bound point to the same find, we are sure key falls in
// range.
assert(curr_level_ == 0 ||
fp_ctx.curr_index_in_curr_level ==
fp_ctx.start_index_in_curr_level ||
user_comparator_->Compare(user_key,
ExtractUserKey(f->smallest_key)) <= 0);
int cmp_smallest = user_comparator_->Compare(
user_key, ExtractUserKey(f->smallest_key));
if (cmp_smallest >= 0) {
cmp_largest = user_comparator_->Compare(
user_key, ExtractUserKey(f->largest_key));
} else {
cmp_largest = -1;
}
// Setup file search bound for the next level based on the
// comparison results
if (curr_level_ > 0) {
file_indexer_->GetNextLevelIndex(
curr_level_, fp_ctx.curr_index_in_curr_level, cmp_smallest,
cmp_largest, &fp_ctx.search_left_bound,
&fp_ctx.search_right_bound);
}
// Key falls out of current file's range
if (cmp_smallest < 0 || cmp_largest > 0) {
next_file_range->SkipKey(batch_iter_);
} else {
file_hit = true;
}
} else {
file_hit = true;
}
if (cmp_largest == 0) {
// cmp_largest is 0, which means the next key will not be in this
// file, so stop looking further. Also don't increment megt_iter_
// as we may have to look for this key in the next file if we don't
// find it in this one
break;
} else {
if (curr_level_ == 0) {
// We need to look through all files in level 0
++fp_ctx.curr_index_in_curr_level;
}
++batch_iter_;
}
if (!file_hit) {
curr_file_index =
(batch_iter_ != current_level_range_.end())
? fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level
: curr_file_level_->num_files;
}
}
*fd = f;
*file_index = curr_file_index;
*is_last_key_in_file = cmp_largest == 0;
return file_hit;
}
FdWithKeyRange* GetNextFile() {
while (!search_ended_) {
// Start searching next level.
if (batch_iter_ == current_level_range_.end()) {
search_ended_ = !PrepareNextLevel();
continue;
} else {
if (maybe_repeat_key_) {
maybe_repeat_key_ = false;
// Check if we found the final value for the last key in the
// previous lookup range. If we did, then there's no need to look
// any further for that key, so advance batch_iter_. Else, keep
// batch_iter_ positioned on that key so we look it up again in
// the next file
// For L0, always advance the key because we will look in the next
// file regardless for all keys not found yet
if (current_level_range_.CheckKeyDone(batch_iter_) ||
curr_level_ == 0) {
++batch_iter_;
}
}
// batch_iter_prev_ will become the start key for the next file
// lookup
batch_iter_prev_ = batch_iter_;
}
MultiGetRange next_file_range(current_level_range_, batch_iter_prev_,
current_level_range_.end());
size_t curr_file_index =
(batch_iter_ != current_level_range_.end())
? fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level
: curr_file_level_->num_files;
FdWithKeyRange* f;
bool is_last_key_in_file;
if (!GetNextFileInLevelWithKeys(&next_file_range, &curr_file_index, &f,
&is_last_key_in_file)) {
search_ended_ = !PrepareNextLevel();
} else {
MultiGetRange::Iterator upper_key = batch_iter_;
if (is_last_key_in_file) {
// Since cmp_largest is 0, batch_iter_ still points to the last key
// that falls in this file, instead of the next one. Increment
// upper_key so we can set the range properly for SST MultiGet
++upper_key;
++(fp_ctx_array_[batch_iter_.index()].curr_index_in_curr_level);
maybe_repeat_key_ = true;
}
// Set the range for this file
current_file_range_ =
MultiGetRange(next_file_range, batch_iter_prev_, upper_key);
returned_file_level_ = curr_level_;
hit_file_level_ = curr_level_;
is_hit_file_last_in_level_ =
curr_file_index == curr_file_level_->num_files - 1;
return f;
}
}
// Search ended
return nullptr;
}
// getter for current file level
// for GET_HIT_L0, GET_HIT_L1 & GET_HIT_L2_AND_UP counts
unsigned int GetHitFileLevel() { return hit_file_level_; }
// Returns true if the most recent "hit file" (i.e., one returned by
// GetNextFile()) is at the last index in its level.
bool IsHitFileLastInLevel() { return is_hit_file_last_in_level_; }
const MultiGetRange& CurrentFileRange() { return current_file_range_; }
private:
unsigned int num_levels_;
unsigned int curr_level_;
unsigned int returned_file_level_;
unsigned int hit_file_level_;
struct FilePickerContext {
int32_t search_left_bound;
int32_t search_right_bound;
unsigned int curr_index_in_curr_level;
unsigned int start_index_in_curr_level;
FilePickerContext(int32_t left, int32_t right)
: search_left_bound(left), search_right_bound(right),
curr_index_in_curr_level(0), start_index_in_curr_level(0) {}
FilePickerContext() = default;
};
std::array<FilePickerContext, MultiGetContext::MAX_BATCH_SIZE> fp_ctx_array_;
MultiGetRange* range_;
// Iterator to iterate through the keys in a MultiGet batch, that gets reset
// at the beginning of each level. Each call to GetNextFile() will position
// batch_iter_ at or right after the last key that was found in the returned
// SST file
MultiGetRange::Iterator batch_iter_;
// An iterator that records the previous position of batch_iter_, i.e last
// key found in the previous SST file, in order to serve as the start of
// the batch key range for the next SST file
MultiGetRange::Iterator batch_iter_prev_;
bool maybe_repeat_key_;
MultiGetRange current_level_range_;
MultiGetRange current_file_range_;
autovector<LevelFilesBrief>* level_files_brief_;
bool search_ended_;
bool is_hit_file_last_in_level_;
LevelFilesBrief* curr_file_level_;
FileIndexer* file_indexer_;
const Comparator* user_comparator_;
const InternalKeyComparator* internal_comparator_;
// Setup local variables to search next level.
// Returns false if there are no more levels to search.
bool PrepareNextLevel() {
if (curr_level_ == 0) {
MultiGetRange::Iterator mget_iter = current_level_range_.begin();
if (fp_ctx_array_[mget_iter.index()].curr_index_in_curr_level <
curr_file_level_->num_files) {
batch_iter_prev_ = current_level_range_.begin();
batch_iter_ = current_level_range_.begin();
return true;
}
}
curr_level_++;
// Reset key range to saved value
while (curr_level_ < num_levels_) {
bool level_contains_keys = false;
curr_file_level_ = &(*level_files_brief_)[curr_level_];
if (curr_file_level_->num_files == 0) {
// When current level is empty, the search bound generated from upper
// level must be [0, -1] or [0, FileIndexer::kLevelMaxIndex] if it is
// also empty.
for (auto mget_iter = current_level_range_.begin();
mget_iter != current_level_range_.end(); ++mget_iter) {
struct FilePickerContext& fp_ctx = fp_ctx_array_[mget_iter.index()];
assert(fp_ctx.search_left_bound == 0);
assert(fp_ctx.search_right_bound == -1 ||
fp_ctx.search_right_bound == FileIndexer::kLevelMaxIndex);
// Since current level is empty, it will need to search all files in
// the next level
fp_ctx.search_left_bound = 0;
fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex;
}
// Skip all subsequent empty levels
do {
++curr_level_;
} while ((curr_level_ < num_levels_) &&
(*level_files_brief_)[curr_level_].num_files == 0);
continue;
}
// Some files may overlap each other. We find
// all files that overlap user_key and process them in order from
// newest to oldest. In the context of merge-operator, this can occur at
// any level. Otherwise, it only occurs at Level-0 (since Put/Deletes
// are always compacted into a single entry).
int32_t start_index = -1;
current_level_range_ =
MultiGetRange(*range_, range_->begin(), range_->end());
for (auto mget_iter = current_level_range_.begin();
mget_iter != current_level_range_.end(); ++mget_iter) {
struct FilePickerContext& fp_ctx = fp_ctx_array_[mget_iter.index()];
if (curr_level_ == 0) {
// On Level-0, we read through all files to check for overlap.
start_index = 0;
level_contains_keys = true;
} else {
// On Level-n (n>=1), files are sorted. Binary search to find the
// earliest file whose largest key >= ikey. Search left bound and
// right bound are used to narrow the range.
if (fp_ctx.search_left_bound <= fp_ctx.search_right_bound) {
if (fp_ctx.search_right_bound == FileIndexer::kLevelMaxIndex) {
fp_ctx.search_right_bound =
static_cast<int32_t>(curr_file_level_->num_files) - 1;
}
// `search_right_bound_` is an inclusive upper-bound, but since it
// was determined based on user key, it is still possible the lookup
// key falls to the right of `search_right_bound_`'s corresponding
// file. So, pass a limit one higher, which allows us to detect this
// case.
Slice& ikey = mget_iter->ikey;
start_index = FindFileInRange(
*internal_comparator_, *curr_file_level_, ikey,
static_cast<uint32_t>(fp_ctx.search_left_bound),
static_cast<uint32_t>(fp_ctx.search_right_bound) + 1);
if (start_index == fp_ctx.search_right_bound + 1) {
// `ikey_` comes after `search_right_bound_`. The lookup key does
// not exist on this level, so let's skip this level and do a full
// binary search on the next level.
fp_ctx.search_left_bound = 0;
fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex;
current_level_range_.SkipKey(mget_iter);
continue;
} else {
level_contains_keys = true;
}
} else {
// search_left_bound > search_right_bound, key does not exist in
// this level. Since no comparison is done in this level, it will
// need to search all files in the next level.
fp_ctx.search_left_bound = 0;
fp_ctx.search_right_bound = FileIndexer::kLevelMaxIndex;
current_level_range_.SkipKey(mget_iter);
continue;
}
}
fp_ctx.start_index_in_curr_level = start_index;
fp_ctx.curr_index_in_curr_level = start_index;
}
if (level_contains_keys) {
batch_iter_prev_ = current_level_range_.begin();
batch_iter_ = current_level_range_.begin();
return true;
}
curr_level_++;
}
// curr_level_ = num_levels_. So, no more levels to search.
return false;
}
};
} // anonymous namespace
VersionStorageInfo::~VersionStorageInfo() { delete[] files_; }
Version::~Version() {
assert(refs_ == 0);
// Remove from linked list
prev_->next_ = next_;
next_->prev_ = prev_;
// Drop references to files
for (int level = 0; level < storage_info_.num_levels_; level++) {
for (size_t i = 0; i < storage_info_.files_[level].size(); i++) {
FileMetaData* f = storage_info_.files_[level][i];
assert(f->refs > 0);
f->refs--;
if (f->refs <= 0) {
assert(cfd_ != nullptr);
uint32_t path_id = f->fd.GetPathId();
assert(path_id < cfd_->ioptions()->cf_paths.size());
vset_->obsolete_files_.push_back(
ObsoleteFileInfo(f, cfd_->ioptions()->cf_paths[path_id].path));
}
}
}
}
int FindFile(const InternalKeyComparator& icmp,
const LevelFilesBrief& file_level,
const Slice& key) {
return FindFileInRange(icmp, file_level, key, 0,
static_cast<uint32_t>(file_level.num_files));
}
void DoGenerateLevelFilesBrief(LevelFilesBrief* file_level,
const std::vector<FileMetaData*>& files,
Arena* arena) {
assert(file_level);
assert(arena);
size_t num = files.size();
file_level->num_files = num;
char* mem = arena->AllocateAligned(num * sizeof(FdWithKeyRange));
file_level->files = new (mem)FdWithKeyRange[num];
for (size_t i = 0; i < num; i++) {
Slice smallest_key = files[i]->smallest.Encode();
Slice largest_key = files[i]->largest.Encode();
// Copy key slice to sequential memory
size_t smallest_size = smallest_key.size();
size_t largest_size = largest_key.size();
mem = arena->AllocateAligned(smallest_size + largest_size);
memcpy(mem, smallest_key.data(), smallest_size);
memcpy(mem + smallest_size, largest_key.data(), largest_size);
FdWithKeyRange& f = file_level->files[i];
f.fd = files[i]->fd;
f.file_metadata = files[i];
f.smallest_key = Slice(mem, smallest_size);
f.largest_key = Slice(mem + smallest_size, largest_size);
}
}
static bool AfterFile(const Comparator* ucmp,
const Slice* user_key, const FdWithKeyRange* f) {
// nullptr user_key occurs before all keys and is therefore never after *f
return (user_key != nullptr &&
ucmp->CompareWithoutTimestamp(*user_key,
ExtractUserKey(f->largest_key)) > 0);
}
static bool BeforeFile(const Comparator* ucmp,
const Slice* user_key, const FdWithKeyRange* f) {
// nullptr user_key occurs after all keys and is therefore never before *f
return (user_key != nullptr &&
ucmp->CompareWithoutTimestamp(*user_key,
ExtractUserKey(f->smallest_key)) < 0);
}
bool SomeFileOverlapsRange(
const InternalKeyComparator& icmp,
bool disjoint_sorted_files,
const LevelFilesBrief& file_level,
const Slice* smallest_user_key,
const Slice* largest_user_key) {
const Comparator* ucmp = icmp.user_comparator();
if (!disjoint_sorted_files) {
// Need to check against all files
for (size_t i = 0; i < file_level.num_files; i++) {
const FdWithKeyRange* f = &(file_level.files[i]);
if (AfterFile(ucmp, smallest_user_key, f) ||
BeforeFile(ucmp, largest_user_key, f)) {
// No overlap
} else {
return true; // Overlap
}
}
return false;
}
// Binary search over file list
uint32_t index = 0;
if (smallest_user_key != nullptr) {
// Find the leftmost possible internal key for smallest_user_key
InternalKey small;
small.SetMinPossibleForUserKey(*smallest_user_key);
index = FindFile(icmp, file_level, small.Encode());
}
if (index >= file_level.num_files) {
// beginning of range is after all files, so no overlap.
return false;
}
return !BeforeFile(ucmp, largest_user_key, &file_level.files[index]);
}
namespace {
class LevelIterator final : public InternalIterator {
public:
LevelIterator(TableCache* table_cache, const ReadOptions& read_options,
const FileOptions& file_options,
const InternalKeyComparator& icomparator,
const LevelFilesBrief* flevel,
const SliceTransform* prefix_extractor, bool should_sample,
HistogramImpl* file_read_hist, TableReaderCaller caller,
bool skip_filters, int level, RangeDelAggregator* range_del_agg,
const std::vector<AtomicCompactionUnitBoundary>*
compaction_boundaries = nullptr)
: table_cache_(table_cache),
read_options_(read_options),
file_options_(file_options),
icomparator_(icomparator),
user_comparator_(icomparator.user_comparator()),
flevel_(flevel),
prefix_extractor_(prefix_extractor),
file_read_hist_(file_read_hist),
should_sample_(should_sample),
caller_(caller),
skip_filters_(skip_filters),
file_index_(flevel_->num_files),
level_(level),
range_del_agg_(range_del_agg),
pinned_iters_mgr_(nullptr),
compaction_boundaries_(compaction_boundaries) {
// Empty level is not supported.
assert(flevel_ != nullptr && flevel_->num_files > 0);
}
~LevelIterator() override { delete file_iter_.Set(nullptr); }
void Seek(const Slice& target) override;
void SeekForPrev(const Slice& target) override;
void SeekToFirst() override;
void SeekToLast() override;
void Next() final override;
bool NextAndGetResult(IterateResult* result) override;
void Prev() override;
bool Valid() const override { return file_iter_.Valid(); }
Slice key() const override {
assert(Valid());
return file_iter_.key();
}
Slice value() const override {
assert(Valid());
return file_iter_.value();
}
Status status() const override {
return file_iter_.iter() ? file_iter_.status() : Status::OK();
}
inline bool MayBeOutOfLowerBound() override {
assert(Valid());
return may_be_out_of_lower_bound_ && file_iter_.MayBeOutOfLowerBound();
}
inline bool MayBeOutOfUpperBound() override {
assert(Valid());
return file_iter_.MayBeOutOfUpperBound();
}
void SetPinnedItersMgr(PinnedIteratorsManager* pinned_iters_mgr) override {
pinned_iters_mgr_ = pinned_iters_mgr;
if (file_iter_.iter()) {
file_iter_.SetPinnedItersMgr(pinned_iters_mgr);
}
}
bool IsKeyPinned() const override {
return pinned_iters_mgr_ && pinned_iters_mgr_->PinningEnabled() &&
file_iter_.iter() && file_iter_.IsKeyPinned();
}
bool IsValuePinned() const override {
return pinned_iters_mgr_ && pinned_iters_mgr_->PinningEnabled() &&
file_iter_.iter() && file_iter_.IsValuePinned();
}
private:
// Return true if at least one invalid file is seen and skipped.
bool SkipEmptyFileForward();
void SkipEmptyFileBackward();
void SetFileIterator(InternalIterator* iter);
void InitFileIterator(size_t new_file_index);
// Called by both of Next() and NextAndGetResult(). Force inline.
void NextImpl() {
assert(Valid());
file_iter_.Next();
SkipEmptyFileForward();
}
const Slice& file_smallest_key(size_t file_index) {
assert(file_index < flevel_->num_files);
return flevel_->files[file_index].smallest_key;
}
bool KeyReachedUpperBound(const Slice& internal_key) {
return read_options_.iterate_upper_bound != nullptr &&
user_comparator_.CompareWithoutTimestamp(
ExtractUserKey(internal_key),
*read_options_.iterate_upper_bound) >= 0;
}
InternalIterator* NewFileIterator() {
assert(file_index_ < flevel_->num_files);
auto file_meta = flevel_->files[file_index_];
if (should_sample_) {
sample_file_read_inc(file_meta.file_metadata);
}
const InternalKey* smallest_compaction_key = nullptr;
const InternalKey* largest_compaction_key = nullptr;
if (compaction_boundaries_ != nullptr) {
smallest_compaction_key = (*compaction_boundaries_)[file_index_].smallest;
largest_compaction_key = (*compaction_boundaries_)[file_index_].largest;
}
CheckMayBeOutOfLowerBound();
return table_cache_->NewIterator(
read_options_, file_options_, icomparator_, *file_meta.file_metadata,
range_del_agg_, prefix_extractor_,
nullptr /* don't need reference to table */, file_read_hist_, caller_,
/*arena=*/nullptr, skip_filters_, level_, smallest_compaction_key,
largest_compaction_key);
}
// Check if current file being fully within iterate_lower_bound.
//
// Note MyRocks may update iterate bounds between seek. To workaround it,
// we need to check and update may_be_out_of_lower_bound_ accordingly.
void CheckMayBeOutOfLowerBound() {
if (read_options_.iterate_lower_bound != nullptr &&
file_index_ < flevel_->num_files) {
may_be_out_of_lower_bound_ =
user_comparator_.Compare(
ExtractUserKey(file_smallest_key(file_index_)),
*read_options_.iterate_lower_bound) < 0;
}
}
TableCache* table_cache_;
const ReadOptions read_options_;
const FileOptions& file_options_;
const InternalKeyComparator& icomparator_;
const UserComparatorWrapper user_comparator_;
const LevelFilesBrief* flevel_;
mutable FileDescriptor current_value_;
// `prefix_extractor_` may be non-null even for total order seek. Checking
// this variable is not the right way to identify whether prefix iterator
// is used.
const SliceTransform* prefix_extractor_;
HistogramImpl* file_read_hist_;
bool should_sample_;
TableReaderCaller caller_;
bool skip_filters_;
bool may_be_out_of_lower_bound_ = true;
size_t file_index_;
int level_;
RangeDelAggregator* range_del_agg_;
IteratorWrapper file_iter_; // May be nullptr
PinnedIteratorsManager* pinned_iters_mgr_;
// To be propagated to RangeDelAggregator in order to safely truncate range
// tombstones.
const std::vector<AtomicCompactionUnitBoundary>* compaction_boundaries_;
};
void LevelIterator::Seek(const Slice& target) {
// Check whether the seek key fall under the same file
bool need_to_reseek = true;
if (file_iter_.iter() != nullptr && file_index_ < flevel_->num_files) {
const FdWithKeyRange& cur_file = flevel_->files[file_index_];
if (icomparator_.InternalKeyComparator::Compare(
target, cur_file.largest_key) <= 0 &&
icomparator_.InternalKeyComparator::Compare(
target, cur_file.smallest_key) >= 0) {
need_to_reseek = false;
assert(static_cast<size_t>(FindFile(icomparator_, *flevel_, target)) ==
file_index_);
}
}
if (need_to_reseek) {
TEST_SYNC_POINT("LevelIterator::Seek:BeforeFindFile");
size_t new_file_index = FindFile(icomparator_, *flevel_, target);
InitFileIterator(new_file_index);
}
if (file_iter_.iter() != nullptr) {
file_iter_.Seek(target);
}
if (SkipEmptyFileForward() && prefix_extractor_ != nullptr &&
!read_options_.total_order_seek && !read_options_.auto_prefix_mode &&
file_iter_.iter() != nullptr && file_iter_.Valid()) {
// We've skipped the file we initially positioned to. In the prefix
// seek case, it is likely that the file is skipped because of
// prefix bloom or hash, where more keys are skipped. We then check
// the current key and invalidate the iterator if the prefix is
// already passed.
// When doing prefix iterator seek, when keys for one prefix have
// been exhausted, it can jump to any key that is larger. Here we are
// enforcing a stricter contract than that, in order to make it easier for
// higher layers (merging and DB iterator) to reason the correctness:
// 1. Within the prefix, the result should be accurate.
// 2. If keys for the prefix is exhausted, it is either positioned to the
// next key after the prefix, or make the iterator invalid.
// A side benefit will be that it invalidates the iterator earlier so that
// the upper level merging iterator can merge fewer child iterators.
Slice target_user_key = ExtractUserKey(target);
Slice file_user_key = ExtractUserKey(file_iter_.key());
if (prefix_extractor_->InDomain(target_user_key) &&
(!prefix_extractor_->InDomain(file_user_key) ||
user_comparator_.Compare(
prefix_extractor_->Transform(target_user_key),
prefix_extractor_->Transform(file_user_key)) != 0)) {
SetFileIterator(nullptr);
}
}
CheckMayBeOutOfLowerBound();
}
void LevelIterator::SeekForPrev(const Slice& target) {
size_t new_file_index = FindFile(icomparator_, *flevel_, target);
if (new_file_index >= flevel_->num_files) {
new_file_index = flevel_->num_files - 1;
}
InitFileIterator(new_file_index);
if (file_iter_.iter() != nullptr) {
file_iter_.SeekForPrev(target);
SkipEmptyFileBackward();
}
CheckMayBeOutOfLowerBound();
}
void LevelIterator::SeekToFirst() {
InitFileIterator(0);
if (file_iter_.iter() != nullptr) {
file_iter_.SeekToFirst();
}
SkipEmptyFileForward();
CheckMayBeOutOfLowerBound();
}
void LevelIterator::SeekToLast() {
InitFileIterator(flevel_->num_files - 1);
if (file_iter_.iter() != nullptr) {
file_iter_.SeekToLast();
}
SkipEmptyFileBackward();
CheckMayBeOutOfLowerBound();
}
void LevelIterator::Next() { NextImpl(); }
bool LevelIterator::NextAndGetResult(IterateResult* result) {
NextImpl();
bool is_valid = Valid();
if (is_valid) {
result->key = key();
result->may_be_out_of_upper_bound = MayBeOutOfUpperBound();
}
return is_valid;
}
void LevelIterator::Prev() {
assert(Valid());
file_iter_.Prev();
SkipEmptyFileBackward();
}
bool LevelIterator::SkipEmptyFileForward() {
bool seen_empty_file = false;
while (file_iter_.iter() == nullptr ||
(!file_iter_.Valid() && file_iter_.status().ok() &&
!file_iter_.iter()->IsOutOfBound())) {
seen_empty_file = true;
// Move to next file
if (file_index_ >= flevel_->num_files - 1) {
// Already at the last file
SetFileIterator(nullptr);
break;
}
if (KeyReachedUpperBound(file_smallest_key(file_index_ + 1))) {
SetFileIterator(nullptr);
break;
}
InitFileIterator(file_index_ + 1);
if (file_iter_.iter() != nullptr) {
file_iter_.SeekToFirst();
}
}
return seen_empty_file;
}
void LevelIterator::SkipEmptyFileBackward() {
while (file_iter_.iter() == nullptr ||
(!file_iter_.Valid() && file_iter_.status().ok())) {
// Move to previous file
if (file_index_ == 0) {
// Already the first file
SetFileIterator(nullptr);
return;
}
InitFileIterator(file_index_ - 1);
if (file_iter_.iter() != nullptr) {
file_iter_.SeekToLast();
}
}
}
void LevelIterator::SetFileIterator(InternalIterator* iter) {
if (pinned_iters_mgr_ && iter) {
iter->SetPinnedItersMgr(pinned_iters_mgr_);
}
InternalIterator* old_iter = file_iter_.Set(iter);
if (pinned_iters_mgr_ && pinned_iters_mgr_->PinningEnabled()) {
pinned_iters_mgr_->PinIterator(old_iter);
} else {
delete old_iter;
}
}
void LevelIterator::InitFileIterator(size_t new_file_index) {
if (new_file_index >= flevel_->num_files) {
file_index_ = new_file_index;
SetFileIterator(nullptr);
return;
} else {
// If the file iterator shows incomplete, we try it again if users seek
// to the same file, as this time we may go to a different data block
// which is cached in block cache.
//
if (file_iter_.iter() != nullptr && !file_iter_.status().IsIncomplete() &&
new_file_index == file_index_) {
// file_iter_ is already constructed with this iterator, so
// no need to change anything
} else {
file_index_ = new_file_index;
InternalIterator* iter = NewFileIterator();
SetFileIterator(iter);
}
}
}
} // anonymous namespace
// A wrapper of version builder which references the current version in
// constructor and unref it in the destructor.
// Both of the constructor and destructor need to be called inside DB Mutex.
class BaseReferencedVersionBuilder {
public:
explicit BaseReferencedVersionBuilder(ColumnFamilyData* cfd)
: version_builder_(new VersionBuilder(
cfd->current()->version_set()->file_options(), cfd->table_cache(),
cfd->current()->storage_info(), cfd->ioptions()->info_log)),
version_(cfd->current()) {
version_->Ref();
}
~BaseReferencedVersionBuilder() {
version_->Unref();
}
VersionBuilder* version_builder() { return version_builder_.get(); }
private:
std::unique_ptr<VersionBuilder> version_builder_;
Version* version_;
};
Status Version::GetTableProperties(std::shared_ptr<const TableProperties>* tp,
const FileMetaData* file_meta,
const std::string* fname) const {
auto table_cache = cfd_->table_cache();
auto ioptions = cfd_->ioptions();
Status s = table_cache->GetTableProperties(
file_options_, cfd_->internal_comparator(), file_meta->fd, tp,
mutable_cf_options_.prefix_extractor.get(), true /* no io */);
if (s.ok()) {
return s;
}
// We only ignore error type `Incomplete` since it's by design that we
// disallow table when it's not in table cache.
if (!s.IsIncomplete()) {
return s;
}
// 2. Table is not present in table cache, we'll read the table properties
// directly from the properties block in the file.
std::unique_ptr<FSRandomAccessFile> file;
std::string file_name;
if (fname != nullptr) {
file_name = *fname;
} else {
file_name =
TableFileName(ioptions->cf_paths, file_meta->fd.GetNumber(),
file_meta->fd.GetPathId());
}
s = ioptions->fs->NewRandomAccessFile(file_name, file_options_, &file,
nullptr);
if (!s.ok()) {
return s;
}
TableProperties* raw_table_properties;
// By setting the magic number to kInvalidTableMagicNumber, we can by
// pass the magic number check in the footer.
std::unique_ptr<RandomAccessFileReader> file_reader(
new RandomAccessFileReader(
std::move(file), file_name, nullptr /* env */, nullptr /* stats */,
0 /* hist_type */, nullptr /* file_read_hist */,
nullptr /* rate_limiter */, ioptions->listeners));
s = ReadTableProperties(
file_reader.get(), file_meta->fd.GetFileSize(),
Footer::kInvalidTableMagicNumber /* table's magic number */, *ioptions,
&raw_table_properties, false /* compression_type_missing */);
if (!s.ok()) {
return s;
}
RecordTick(ioptions->statistics, NUMBER_DIRECT_LOAD_TABLE_PROPERTIES);
*tp = std::shared_ptr<const TableProperties>(raw_table_properties);
return s;
}
Status Version::GetPropertiesOfAllTables(TablePropertiesCollection* props) {
Status s;
for (int level = 0; level < storage_info_.num_levels_; level++) {
s = GetPropertiesOfAllTables(props, level);
if (!s.ok()) {
return s;
}
}
return Status::OK();
}
Status Version::TablesRangeTombstoneSummary(int max_entries_to_print,
std::string* out_str) {
if (max_entries_to_print <= 0) {
return Status::OK();
}
int num_entries_left = max_entries_to_print;
std::stringstream ss;
for (int level = 0; level < storage_info_.num_levels_; level++) {
for (const auto& file_meta : storage_info_.files_[level]) {
auto fname =
TableFileName(cfd_->ioptions()->cf_paths, file_meta->fd.GetNumber(),
file_meta->fd.GetPathId());
ss << "=== file : " << fname << " ===\n";
TableCache* table_cache = cfd_->table_cache();
std::unique_ptr<FragmentedRangeTombstoneIterator> tombstone_iter;
Status s = table_cache->GetRangeTombstoneIterator(
ReadOptions(), cfd_->internal_comparator(), *file_meta,
&tombstone_iter);
if (!s.ok()) {
return s;
}
if (tombstone_iter) {
tombstone_iter->SeekToFirst();
while (tombstone_iter->Valid() && num_entries_left > 0) {
ss << "start: " << tombstone_iter->start_key().ToString(true)
<< " end: " << tombstone_iter->end_key().ToString(true)
<< " seq: " << tombstone_iter->seq() << '\n';
tombstone_iter->Next();
num_entries_left--;
}
if (num_entries_left <= 0) {
break;
}
}
}
if (num_entries_left <= 0) {
break;
}
}
assert(num_entries_left >= 0);
if (num_entries_left <= 0) {
ss << "(results may not be complete)\n";
}
*out_str = ss.str();
return Status::OK();
}
Status Version::GetPropertiesOfAllTables(TablePropertiesCollection* props,
int level) {
for (const auto& file_meta : storage_info_.files_[level]) {
auto fname =
TableFileName(cfd_->ioptions()->cf_paths, file_meta->fd.GetNumber(),
file_meta->fd.GetPathId());
// 1. If the table is already present in table cache, load table
// properties from there.
std::shared_ptr<const TableProperties> table_properties;
Status s = GetTableProperties(&table_properties, file_meta, &fname);
if (s.ok()) {
props->insert({fname, table_properties});
} else {
return s;
}
}
return Status::OK();
}
Status Version::GetPropertiesOfTablesInRange(
const Range* range, std::size_t n, TablePropertiesCollection* props) const {
for (int level = 0; level < storage_info_.num_non_empty_levels(); level++) {
for (decltype(n) i = 0; i < n; i++) {
// Convert user_key into a corresponding internal key.
InternalKey k1(range[i].start, kMaxSequenceNumber, kValueTypeForSeek);
InternalKey k2(range[i].limit, kMaxSequenceNumber, kValueTypeForSeek);
std::vector<FileMetaData*> files;
storage_info_.GetOverlappingInputs(level, &k1, &k2, &files, -1, nullptr,
false);
for (const auto& file_meta : files) {
auto fname =
TableFileName(cfd_->ioptions()->cf_paths,
file_meta->fd.GetNumber(), file_meta->fd.GetPathId());
if (props->count(fname) == 0) {
// 1. If the table is already present in table cache, load table
// properties from there.
std::shared_ptr<const TableProperties> table_properties;
Status s = GetTableProperties(&table_properties, file_meta, &fname);
if (s.ok()) {
props->insert({fname, table_properties});
} else {
return s;
}
}
}
}
}
return Status::OK();
}
Status Version::GetAggregatedTableProperties(
std::shared_ptr<const TableProperties>* tp, int level) {
TablePropertiesCollection props;
Status s;
if (level < 0) {
s = GetPropertiesOfAllTables(&props);
} else {
s = GetPropertiesOfAllTables(&props, level);
}
if (!s.ok()) {
return s;
}
auto* new_tp = new TableProperties();
for (const auto& item : props) {
new_tp->Add(*item.second);
}
tp->reset(new_tp);
return Status::OK();
}
size_t Version::GetMemoryUsageByTableReaders() {
size_t total_usage = 0;
for (auto& file_level : storage_info_.level_files_brief_) {
for (size_t i = 0; i < file_level.num_files; i++) {
total_usage += cfd_->table_cache()->GetMemoryUsageByTableReader(
file_options_, cfd_->internal_comparator(), file_level.files[i].fd,
mutable_cf_options_.prefix_extractor.get());
}
}
return total_usage;
}
void Version::GetColumnFamilyMetaData(ColumnFamilyMetaData* cf_meta) {
assert(cf_meta);
assert(cfd_);
cf_meta->name = cfd_->GetName();
cf_meta->size = 0;
cf_meta->file_count = 0;
cf_meta->levels.clear();
auto* ioptions = cfd_->ioptions();
auto* vstorage = storage_info();
for (int level = 0; level < cfd_->NumberLevels(); level++) {
uint64_t level_size = 0;
cf_meta->file_count += vstorage->LevelFiles(level).size();
std::vector<SstFileMetaData> files;
for (const auto& file : vstorage->LevelFiles(level)) {
uint32_t path_id = file->fd.GetPathId();
std::string file_path;
if (path_id < ioptions->cf_paths.size()) {
file_path = ioptions->cf_paths[path_id].path;
} else {
assert(!ioptions->cf_paths.empty());
file_path = ioptions->cf_paths.back().path;
}
const uint64_t file_number = file->fd.GetNumber();
files.emplace_back(SstFileMetaData{
MakeTableFileName("", file_number), file_number, file_path,
static_cast<size_t>(file->fd.GetFileSize()), file->fd.smallest_seqno,
file->fd.largest_seqno, file->smallest.user_key().ToString(),
file->largest.user_key().ToString(),
file->stats.num_reads_sampled.load(std::memory_order_relaxed),
file->being_compacted, file->oldest_blob_file_number,
file->TryGetOldestAncesterTime(), file->TryGetFileCreationTime(),
file->file_checksum, file->file_checksum_func_name});
files.back().num_entries = file->num_entries;
files.back().num_deletions = file->num_deletions;
level_size += file->fd.GetFileSize();
}
cf_meta->levels.emplace_back(
level, level_size, std::move(files));
cf_meta->size += level_size;
}
}
uint64_t Version::GetSstFilesSize() {
uint64_t sst_files_size = 0;
for (int level = 0; level < storage_info_.num_levels_; level++) {
for (const auto& file_meta : storage_info_.LevelFiles(level)) {
sst_files_size += file_meta->fd.GetFileSize();
}
}
return sst_files_size;
}
void Version::GetCreationTimeOfOldestFile(uint64_t* creation_time) {
uint64_t oldest_time = port::kMaxUint64;
for (int level = 0; level < storage_info_.num_non_empty_levels_; level++) {
for (FileMetaData* meta : storage_info_.LevelFiles(level)) {
assert(meta->fd.table_reader != nullptr);
uint64_t file_creation_time = meta->TryGetFileCreationTime();
if (file_creation_time == kUnknownFileCreationTime) {
*creation_time = 0;
return;
}
if (file_creation_time < oldest_time) {
oldest_time = file_creation_time;
}
}
}
*creation_time = oldest_time;
}
uint64_t VersionStorageInfo::GetEstimatedActiveKeys() const {
// Estimation will be inaccurate when:
// (1) there exist merge keys
// (2) keys are directly overwritten
// (3) deletion on non-existing keys
// (4) low number of samples
if (current_num_samples_ == 0) {
return 0;
}
if (current_num_non_deletions_ <= current_num_deletions_) {
return 0;
}
uint64_t est = current_num_non_deletions_ - current_num_deletions_;
uint64_t file_count = 0;
for (int level = 0; level < num_levels_; ++level) {
file_count += files_[level].size();
}
if (current_num_samples_ < file_count) {
// casting to avoid overflowing
return
static_cast<uint64_t>(
(est * static_cast<double>(file_count) / current_num_samples_)
);
} else {
return est;
}
}
double VersionStorageInfo::GetEstimatedCompressionRatioAtLevel(
int level) const {
assert(level < num_levels_);
uint64_t sum_file_size_bytes = 0;
uint64_t sum_data_size_bytes = 0;
for (auto* file_meta : files_[level]) {
sum_file_size_bytes += file_meta->fd.GetFileSize();
sum_data_size_bytes += file_meta->raw_key_size + file_meta->raw_value_size;
}
if (sum_file_size_bytes == 0) {
return -1.0;
}
return static_cast<double>(sum_data_size_bytes) / sum_file_size_bytes;
}
void Version::AddIterators(const ReadOptions& read_options,
const FileOptions& soptions,
MergeIteratorBuilder* merge_iter_builder,
RangeDelAggregator* range_del_agg) {
assert(storage_info_.finalized_);
for (int level = 0; level < storage_info_.num_non_empty_levels(); level++) {
AddIteratorsForLevel(read_options, soptions, merge_iter_builder, level,
range_del_agg);
}
}
void Version::AddIteratorsForLevel(const ReadOptions& read_options,
const FileOptions& soptions,
MergeIteratorBuilder* merge_iter_builder,
int level,
RangeDelAggregator* range_del_agg) {
assert(storage_info_.finalized_);
if (level >= storage_info_.num_non_empty_levels()) {
// This is an empty level
return;
} else if (storage_info_.LevelFilesBrief(level).num_files == 0) {
// No files in this level
return;
}
bool should_sample = should_sample_file_read();
auto* arena = merge_iter_builder->GetArena();
if (level == 0) {
// Merge all level zero files together since they may overlap
for (size_t i = 0; i < storage_info_.LevelFilesBrief(0).num_files; i++) {
const auto& file = storage_info_.LevelFilesBrief(0).files[i];
merge_iter_builder->AddIterator(cfd_->table_cache()->NewIterator(
read_options, soptions, cfd_->internal_comparator(),
*file.file_metadata, range_del_agg,
mutable_cf_options_.prefix_extractor.get(), nullptr,
cfd_->internal_stats()->GetFileReadHist(0),
TableReaderCaller::kUserIterator, arena,
/*skip_filters=*/false, /*level=*/0,
/*smallest_compaction_key=*/nullptr,
/*largest_compaction_key=*/nullptr));
}
if (should_sample) {
// Count ones for every L0 files. This is done per iterator creation
// rather than Seek(), while files in other levels are recored per seek.
// If users execute one range query per iterator, there may be some
// discrepancy here.
for (FileMetaData* meta : storage_info_.LevelFiles(0)) {
sample_file_read_inc(meta);
}
}
} else if (storage_info_.LevelFilesBrief(level).num_files > 0) {
// For levels > 0, we can use a concatenating iterator that sequentially
// walks through the non-overlapping files in the level, opening them
// lazily.
auto* mem = arena->AllocateAligned(sizeof(LevelIterator));
merge_iter_builder->AddIterator(new (mem) LevelIterator(
cfd_->table_cache(), read_options, soptions,
cfd_->internal_comparator(), &storage_info_.LevelFilesBrief(level),
mutable_cf_options_.prefix_extractor.get(), should_sample_file_read(),
cfd_->internal_stats()->GetFileReadHist(level),
TableReaderCaller::kUserIterator, IsFilterSkipped(level), level,
range_del_agg, /*largest_compaction_key=*/nullptr));
}
}
Status Version::OverlapWithLevelIterator(const ReadOptions& read_options,
const FileOptions& file_options,
const Slice& smallest_user_key,
const Slice& largest_user_key,
int level, bool* overlap) {
assert(storage_info_.finalized_);
auto icmp = cfd_->internal_comparator();
auto ucmp = icmp.user_comparator();
Arena arena;
Status status;
ReadRangeDelAggregator range_del_agg(&icmp,
kMaxSequenceNumber /* upper_bound */);
*overlap = false;
if (level == 0) {
for (size_t i = 0; i < storage_info_.LevelFilesBrief(0).num_files; i++) {
const auto file = &storage_info_.LevelFilesBrief(0).files[i];
if (AfterFile(ucmp, &smallest_user_key, file) ||
BeforeFile(ucmp, &largest_user_key, file)) {
continue;
}
ScopedArenaIterator iter(cfd_->table_cache()->NewIterator(
read_options, file_options, cfd_->internal_comparator(),
*file->file_metadata, &range_del_agg,
mutable_cf_options_.prefix_extractor.get(), nullptr,
cfd_->internal_stats()->GetFileReadHist(0),
TableReaderCaller::kUserIterator, &arena,
/*skip_filters=*/false, /*level=*/0,
/*smallest_compaction_key=*/nullptr,
/*largest_compaction_key=*/nullptr));
status = OverlapWithIterator(
ucmp, smallest_user_key, largest_user_key, iter.get(), overlap);
if (!status.ok() || *overlap) {
break;
}
}
} else if (storage_info_.LevelFilesBrief(level).num_files > 0) {
auto mem = arena.AllocateAligned(sizeof(LevelIterator));
ScopedArenaIterator iter(new (mem) LevelIterator(
cfd_->table_cache(), read_options, file_options,
cfd_->internal_comparator(), &storage_info_.LevelFilesBrief(level),
mutable_cf_options_.prefix_extractor.get(), should_sample_file_read(),
cfd_->internal_stats()->GetFileReadHist(level),
TableReaderCaller::kUserIterator, IsFilterSkipped(level), level,
&range_del_agg));
status = OverlapWithIterator(
ucmp, smallest_user_key, largest_user_key, iter.get(), overlap);
}
if (status.ok() && *overlap == false &&
range_del_agg.IsRangeOverlapped(smallest_user_key, largest_user_key)) {
*overlap = true;
}
return status;
}
VersionStorageInfo::VersionStorageInfo(
const InternalKeyComparator* internal_comparator,
const Comparator* user_comparator, int levels,
CompactionStyle compaction_style, VersionStorageInfo* ref_vstorage,
bool _force_consistency_checks)
: internal_comparator_(internal_comparator),
user_comparator_(user_comparator),
// cfd is nullptr if Version is dummy
num_levels_(levels),
num_non_empty_levels_(0),
file_indexer_(user_comparator),
compaction_style_(compaction_style),
files_(new std::vector<FileMetaData*>[num_levels_]),
base_level_(num_levels_ == 1 ? -1 : 1),
level_multiplier_(0.0),
files_by_compaction_pri_(num_levels_),
level0_non_overlapping_(false),
next_file_to_compact_by_size_(num_levels_),
compaction_score_(num_levels_),
compaction_level_(num_levels_),
l0_delay_trigger_count_(0),
accumulated_file_size_(0),
accumulated_raw_key_size_(0),
accumulated_raw_value_size_(0),
accumulated_num_non_deletions_(0),
accumulated_num_deletions_(0),
current_num_non_deletions_(0),
current_num_deletions_(0),
current_num_samples_(0),
estimated_compaction_needed_bytes_(0),
finalized_(false),
force_consistency_checks_(_force_consistency_checks) {
if (ref_vstorage != nullptr) {
accumulated_file_size_ = ref_vstorage->accumulated_file_size_;
accumulated_raw_key_size_ = ref_vstorage->accumulated_raw_key_size_;
accumulated_raw_value_size_ = ref_vstorage->accumulated_raw_value_size_;
accumulated_num_non_deletions_ =
ref_vstorage->accumulated_num_non_deletions_;
accumulated_num_deletions_ = ref_vstorage->accumulated_num_deletions_;
current_num_non_deletions_ = ref_vstorage->current_num_non_deletions_;
current_num_deletions_ = ref_vstorage->current_num_deletions_;
current_num_samples_ = ref_vstorage->current_num_samples_;
oldest_snapshot_seqnum_ = ref_vstorage->oldest_snapshot_seqnum_;
}
}
Version::Version(ColumnFamilyData* column_family_data, VersionSet* vset,
const FileOptions& file_opt,
const MutableCFOptions mutable_cf_options,
uint64_t version_number)
: env_(vset->env_),
cfd_(column_family_data),
info_log_((cfd_ == nullptr) ? nullptr : cfd_->ioptions()->info_log),
db_statistics_((cfd_ == nullptr) ? nullptr
: cfd_->ioptions()->statistics),
table_cache_((cfd_ == nullptr) ? nullptr : cfd_->table_cache()),
merge_operator_((cfd_ == nullptr) ? nullptr
: cfd_->ioptions()->merge_operator),
storage_info_(
(cfd_ == nullptr) ? nullptr : &cfd_->internal_comparator(),
(cfd_ == nullptr) ? nullptr : cfd_->user_comparator(),
cfd_ == nullptr ? 0 : cfd_->NumberLevels(),
cfd_ == nullptr ? kCompactionStyleLevel
: cfd_->ioptions()->compaction_style,
(cfd_ == nullptr || cfd_->current() == nullptr)
? nullptr
: cfd_->current()->storage_info(),
cfd_ == nullptr ? false : cfd_->ioptions()->force_consistency_checks),
vset_(vset),
next_(this),
prev_(this),
refs_(0),
file_options_(file_opt),
mutable_cf_options_(mutable_cf_options),
version_number_(version_number) {}
void Version::Get(const ReadOptions& read_options, const LookupKey& k,
PinnableSlice* value, std::string* timestamp, Status* status,
MergeContext* merge_context,
SequenceNumber* max_covering_tombstone_seq, bool* value_found,
bool* key_exists, SequenceNumber* seq, ReadCallback* callback,
bool* is_blob, bool do_merge) {
Slice ikey = k.internal_key();
Slice user_key = k.user_key();
assert(status->ok() || status->IsMergeInProgress());
if (key_exists != nullptr) {
// will falsify below if not found
*key_exists = true;
}
PinnedIteratorsManager pinned_iters_mgr;
uint64_t tracing_get_id = BlockCacheTraceHelper::kReservedGetId;
if (vset_ && vset_->block_cache_tracer_ &&
vset_->block_cache_tracer_->is_tracing_enabled()) {
tracing_get_id = vset_->block_cache_tracer_->NextGetId();
}
GetContext get_context(
user_comparator(), merge_operator_, info_log_, db_statistics_,
status->ok() ? GetContext::kNotFound : GetContext::kMerge, user_key,
do_merge ? value : nullptr, do_merge ? timestamp : nullptr, value_found,
merge_context, do_merge, max_covering_tombstone_seq, this->env_, seq,
merge_operator_ ? &pinned_iters_mgr : nullptr, callback, is_blob,
tracing_get_id);
// Pin blocks that we read to hold merge operands
if (merge_operator_) {
pinned_iters_mgr.StartPinning();
}
FilePicker fp(
storage_info_.files_, user_key, ikey, &storage_info_.level_files_brief_,
storage_info_.num_non_empty_levels_, &storage_info_.file_indexer_,
user_comparator(), internal_comparator());
FdWithKeyRange* f = fp.GetNextFile();
while (f != nullptr) {
if (*max_covering_tombstone_seq > 0) {
// The remaining files we look at will only contain covered keys, so we
// stop here.
break;
}
if (get_context.sample()) {
sample_file_read_inc(f->file_metadata);
}
bool timer_enabled =
GetPerfLevel() >= PerfLevel::kEnableTimeExceptForMutex &&
get_perf_context()->per_level_perf_context_enabled;
StopWatchNano timer(env_, timer_enabled /* auto_start */);
*status = table_cache_->Get(
read_options, *internal_comparator(), *f->file_metadata, ikey,
&get_context, mutable_cf_options_.prefix_extractor.get(),
cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()),
IsFilterSkipped(static_cast<int>(fp.GetHitFileLevel()),
fp.IsHitFileLastInLevel()),
fp.GetCurrentLevel());
// TODO: examine the behavior for corrupted key
if (timer_enabled) {
PERF_COUNTER_BY_LEVEL_ADD(get_from_table_nanos, timer.ElapsedNanos(),
fp.GetCurrentLevel());
}
if (!status->ok()) {
return;
}
// report the counters before returning
if (get_context.State() != GetContext::kNotFound &&
get_context.State() != GetContext::kMerge &&
db_statistics_ != nullptr) {
get_context.ReportCounters();
}
switch (get_context.State()) {
case GetContext::kNotFound:
// Keep searching in other files
break;
case GetContext::kMerge:
// TODO: update per-level perfcontext user_key_return_count for kMerge
break;
case GetContext::kFound:
if (fp.GetHitFileLevel() == 0) {
RecordTick(db_statistics_, GET_HIT_L0);
} else if (fp.GetHitFileLevel() == 1) {
RecordTick(db_statistics_, GET_HIT_L1);
} else if (fp.GetHitFileLevel() >= 2) {
RecordTick(db_statistics_, GET_HIT_L2_AND_UP);
}
PERF_COUNTER_BY_LEVEL_ADD(user_key_return_count, 1,
fp.GetHitFileLevel());
return;
case GetContext::kDeleted:
// Use empty error message for speed
*status = Status::NotFound();
return;
case GetContext::kCorrupt:
*status = Status::Corruption("corrupted key for ", user_key);
return;
case GetContext::kBlobIndex:
ROCKS_LOG_ERROR(info_log_, "Encounter unexpected blob index.");
*status = Status::NotSupported(
"Encounter unexpected blob index. Please open DB with "
"ROCKSDB_NAMESPACE::blob_db::BlobDB instead.");
return;
}
f = fp.GetNextFile();
}
if (db_statistics_ != nullptr) {
get_context.ReportCounters();
}
if (GetContext::kMerge == get_context.State()) {
if (!do_merge) {
*status = Status::OK();
return;
}
if (!merge_operator_) {
*status = Status::InvalidArgument(
"merge_operator is not properly initialized.");
return;
}
// merge_operands are in saver and we hit the beginning of the key history
// do a final merge of nullptr and operands;
std::string* str_value = value != nullptr ? value->GetSelf() : nullptr;
*status = MergeHelper::TimedFullMerge(
merge_operator_, user_key, nullptr, merge_context->GetOperands(),
str_value, info_log_, db_statistics_, env_,
nullptr /* result_operand */, true);
if (LIKELY(value != nullptr)) {
value->PinSelf();
}
} else {
if (key_exists != nullptr) {
*key_exists = false;
}
*status = Status::NotFound(); // Use an empty error message for speed
}
}
void Version::MultiGet(const ReadOptions& read_options, MultiGetRange* range,
ReadCallback* callback, bool* is_blob) {
PinnedIteratorsManager pinned_iters_mgr;
// Pin blocks that we read to hold merge operands
if (merge_operator_) {
pinned_iters_mgr.StartPinning();
}
uint64_t tracing_mget_id = BlockCacheTraceHelper::kReservedGetId;
if (vset_ && vset_->block_cache_tracer_ &&
vset_->block_cache_tracer_->is_tracing_enabled()) {
tracing_mget_id = vset_->block_cache_tracer_->NextGetId();
}
// Even though we know the batch size won't be > MAX_BATCH_SIZE,
// use autovector in order to avoid unnecessary construction of GetContext
// objects, which is expensive
autovector<GetContext, 16> get_ctx;
for (auto iter = range->begin(); iter != range->end(); ++iter) {
assert(iter->s->ok() || iter->s->IsMergeInProgress());
get_ctx.emplace_back(
user_comparator(), merge_operator_, info_log_, db_statistics_,
iter->s->ok() ? GetContext::kNotFound : GetContext::kMerge, iter->ukey,
iter->value, /*timestamp*/ nullptr, nullptr, &(iter->merge_context),
true, &iter->max_covering_tombstone_seq, this->env_, nullptr,
merge_operator_ ? &pinned_iters_mgr : nullptr, callback, is_blob,
tracing_mget_id);
// MergeInProgress status, if set, has been transferred to the get_context
// state, so we set status to ok here. From now on, the iter status will
// be used for IO errors, and get_context state will be used for any
// key level errors
*(iter->s) = Status::OK();
}
int get_ctx_index = 0;
for (auto iter = range->begin(); iter != range->end();
++iter, get_ctx_index++) {
iter->get_context = &(get_ctx[get_ctx_index]);
}
MultiGetRange file_picker_range(*range, range->begin(), range->end());
FilePickerMultiGet fp(
&file_picker_range,
&storage_info_.level_files_brief_, storage_info_.num_non_empty_levels_,
&storage_info_.file_indexer_, user_comparator(), internal_comparator());
FdWithKeyRange* f = fp.GetNextFile();
while (f != nullptr) {
MultiGetRange file_range = fp.CurrentFileRange();
bool timer_enabled =
GetPerfLevel() >= PerfLevel::kEnableTimeExceptForMutex &&
get_perf_context()->per_level_perf_context_enabled;
StopWatchNano timer(env_, timer_enabled /* auto_start */);
Status s = table_cache_->MultiGet(
read_options, *internal_comparator(), *f->file_metadata, &file_range,
mutable_cf_options_.prefix_extractor.get(),
cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()),
IsFilterSkipped(static_cast<int>(fp.GetHitFileLevel()),
fp.IsHitFileLastInLevel()),
fp.GetCurrentLevel());
// TODO: examine the behavior for corrupted key
if (timer_enabled) {
PERF_COUNTER_BY_LEVEL_ADD(get_from_table_nanos, timer.ElapsedNanos(),
fp.GetCurrentLevel());
}
if (!s.ok()) {
// TODO: Set status for individual keys appropriately
for (auto iter = file_range.begin(); iter != file_range.end(); ++iter) {
*iter->s = s;
file_range.MarkKeyDone(iter);
}
return;
}
uint64_t batch_size = 0;
for (auto iter = file_range.begin(); iter != file_range.end(); ++iter) {
GetContext& get_context = *iter->get_context;
Status* status = iter->s;
// The Status in the KeyContext takes precedence over GetContext state
// Status may be an error if there were any IO errors in the table
// reader. We never expect Status to be NotFound(), as that is
// determined by get_context
assert(!status->IsNotFound());
if (!status->ok()) {
file_range.MarkKeyDone(iter);
continue;
}
if (get_context.sample()) {
sample_file_read_inc(f->file_metadata);
}
batch_size++;
// report the counters before returning
if (get_context.State() != GetContext::kNotFound &&
get_context.State() != GetContext::kMerge &&
db_statistics_ != nullptr) {
get_context.ReportCounters();
} else {
if (iter->max_covering_tombstone_seq > 0) {
// The remaining files we look at will only contain covered keys, so
// we stop here for this key
file_picker_range.SkipKey(iter);
}
}
switch (get_context.State()) {
case GetContext::kNotFound:
// Keep searching in other files
break;
case GetContext::kMerge:
// TODO: update per-level perfcontext user_key_return_count for kMerge
break;
case GetContext::kFound:
if (fp.GetHitFileLevel() == 0) {
RecordTick(db_statistics_, GET_HIT_L0);
} else if (fp.GetHitFileLevel() == 1) {
RecordTick(db_statistics_, GET_HIT_L1);
} else if (fp.GetHitFileLevel() >= 2) {
RecordTick(db_statistics_, GET_HIT_L2_AND_UP);
}
PERF_COUNTER_BY_LEVEL_ADD(user_key_return_count, 1,
fp.GetHitFileLevel());
file_range.MarkKeyDone(iter);
continue;
case GetContext::kDeleted:
// Use empty error message for speed
*status = Status::NotFound();
file_range.MarkKeyDone(iter);
continue;
case GetContext::kCorrupt:
*status =
Status::Corruption("corrupted key for ", iter->lkey->user_key());
file_range.MarkKeyDone(iter);
continue;
case GetContext::kBlobIndex:
ROCKS_LOG_ERROR(info_log_, "Encounter unexpected blob index.");
*status = Status::NotSupported(
"Encounter unexpected blob index. Please open DB with "
"ROCKSDB_NAMESPACE::blob_db::BlobDB instead.");
file_range.MarkKeyDone(iter);
continue;
}
}
RecordInHistogram(db_statistics_, SST_BATCH_SIZE, batch_size);
if (file_picker_range.empty()) {
break;
}
f = fp.GetNextFile();
}
// Process any left over keys
for (auto iter = range->begin(); iter != range->end(); ++iter) {
GetContext& get_context = *iter->get_context;
Status* status = iter->s;
Slice user_key = iter->lkey->user_key();
if (db_statistics_ != nullptr) {
get_context.ReportCounters();
}
if (GetContext::kMerge == get_context.State()) {
if (!merge_operator_) {
*status = Status::InvalidArgument(
"merge_operator is not properly initialized.");
range->MarkKeyDone(iter);
continue;
}
// merge_operands are in saver and we hit the beginning of the key history
// do a final merge of nullptr and operands;
std::string* str_value =
iter->value != nullptr ? iter->value->GetSelf() : nullptr;
*status = MergeHelper::TimedFullMerge(
merge_operator_, user_key, nullptr, iter->merge_context.GetOperands(),
str_value, info_log_, db_statistics_, env_,
nullptr /* result_operand */, true);
if (LIKELY(iter->value != nullptr)) {
iter->value->PinSelf();
}
} else {
range->MarkKeyDone(iter);
*status = Status::NotFound(); // Use an empty error message for speed
}
}
}
bool Version::IsFilterSkipped(int level, bool is_file_last_in_level) {
// Reaching the bottom level implies misses at all upper levels, so we'll
// skip checking the filters when we predict a hit.
return cfd_->ioptions()->optimize_filters_for_hits &&
(level > 0 || is_file_last_in_level) &&
level == storage_info_.num_non_empty_levels() - 1;
}
void VersionStorageInfo::GenerateLevelFilesBrief() {
level_files_brief_.resize(num_non_empty_levels_);
for (int level = 0; level < num_non_empty_levels_; level++) {
DoGenerateLevelFilesBrief(
&level_files_brief_[level], files_[level], &arena_);
}
}
void Version::PrepareApply(
const MutableCFOptions& mutable_cf_options,
bool update_stats) {
UpdateAccumulatedStats(update_stats);
storage_info_.UpdateNumNonEmptyLevels();
storage_info_.CalculateBaseBytes(*cfd_->ioptions(), mutable_cf_options);
storage_info_.UpdateFilesByCompactionPri(cfd_->ioptions()->compaction_pri);
storage_info_.GenerateFileIndexer();
storage_info_.GenerateLevelFilesBrief();
storage_info_.GenerateLevel0NonOverlapping();
storage_info_.GenerateBottommostFiles();
}
bool Version::MaybeInitializeFileMetaData(FileMetaData* file_meta) {
if (file_meta->init_stats_from_file ||
file_meta->compensated_file_size > 0) {
return false;
}
std::shared_ptr<const TableProperties> tp;
Status s = GetTableProperties(&tp, file_meta);
file_meta->init_stats_from_file = true;
if (!s.ok()) {
ROCKS_LOG_ERROR(vset_->db_options_->info_log,
"Unable to load table properties for file %" PRIu64
" --- %s\n",
file_meta->fd.GetNumber(), s.ToString().c_str());
return false;
}
if (tp.get() == nullptr) return false;
file_meta->num_entries = tp->num_entries;
file_meta->num_deletions = tp->num_deletions;
file_meta->raw_value_size = tp->raw_value_size;
file_meta->raw_key_size = tp->raw_key_size;
return true;
}
void VersionStorageInfo::UpdateAccumulatedStats(FileMetaData* file_meta) {
TEST_SYNC_POINT_CALLBACK("VersionStorageInfo::UpdateAccumulatedStats",
nullptr);
assert(file_meta->init_stats_from_file);
accumulated_file_size_ += file_meta->fd.GetFileSize();
accumulated_raw_key_size_ += file_meta->raw_key_size;
accumulated_raw_value_size_ += file_meta->raw_value_size;
accumulated_num_non_deletions_ +=
file_meta->num_entries - file_meta->num_deletions;
accumulated_num_deletions_ += file_meta->num_deletions;
current_num_non_deletions_ +=
file_meta->num_entries - file_meta->num_deletions;
current_num_deletions_ += file_meta->num_deletions;
current_num_samples_++;
}
void VersionStorageInfo::RemoveCurrentStats(FileMetaData* file_meta) {
if (file_meta->init_stats_from_file) {
current_num_non_deletions_ -=
file_meta->num_entries - file_meta->num_deletions;
current_num_deletions_ -= file_meta->num_deletions;
current_num_samples_--;
}
}
void Version::UpdateAccumulatedStats(bool update_stats) {
if (update_stats) {
// maximum number of table properties loaded from files.
const int kMaxInitCount = 20;
int init_count = 0;
// here only the first kMaxInitCount files which haven't been
// initialized from file will be updated with num_deletions.
// The motivation here is to cap the maximum I/O per Version creation.
// The reason for choosing files from lower-level instead of higher-level
// is that such design is able to propagate the initialization from
// lower-level to higher-level: When the num_deletions of lower-level
// files are updated, it will make the lower-level files have accurate
// compensated_file_size, making lower-level to higher-level compaction
// will be triggered, which creates higher-level files whose num_deletions
// will be updated here.
for (int level = 0;
level < storage_info_.num_levels_ && init_count < kMaxInitCount;
++level) {
for (auto* file_meta : storage_info_.files_[level]) {
if (MaybeInitializeFileMetaData(file_meta)) {
// each FileMeta will be initialized only once.
storage_info_.UpdateAccumulatedStats(file_meta);
// when option "max_open_files" is -1, all the file metadata has
// already been read, so MaybeInitializeFileMetaData() won't incur
// any I/O cost. "max_open_files=-1" means that the table cache passed
// to the VersionSet and then to the ColumnFamilySet has a size of
// TableCache::kInfiniteCapacity
if (vset_->GetColumnFamilySet()->get_table_cache()->GetCapacity() ==
TableCache::kInfiniteCapacity) {
continue;
}
if (++init_count >= kMaxInitCount) {
break;
}
}
}
}
// In case all sampled-files contain only deletion entries, then we
// load the table-property of a file in higher-level to initialize
// that value.
for (int level = storage_info_.num_levels_ - 1;
storage_info_.accumulated_raw_value_size_ == 0 && level >= 0;
--level) {
for (int i = static_cast<int>(storage_info_.files_[level].size()) - 1;
storage_info_.accumulated_raw_value_size_ == 0 && i >= 0; --i) {
if (MaybeInitializeFileMetaData(storage_info_.files_[level][i])) {
storage_info_.UpdateAccumulatedStats(storage_info_.files_[level][i]);
}
}
}
}
storage_info_.ComputeCompensatedSizes();
}
void VersionStorageInfo::ComputeCompensatedSizes() {
static const int kDeletionWeightOnCompaction = 2;
uint64_t average_value_size = GetAverageValueSize();
// compute the compensated size
for (int level = 0; level < num_levels_; level++) {
for (auto* file_meta : files_[level]) {
// Here we only compute compensated_file_size for those file_meta
// which compensated_file_size is uninitialized (== 0). This is true only
// for files that have been created right now and no other thread has
// access to them. That's why we can safely mutate compensated_file_size.
if (file_meta->compensated_file_size == 0) {
file_meta->compensated_file_size = file_meta->fd.GetFileSize();
// Here we only boost the size of deletion entries of a file only
// when the number of deletion entries is greater than the number of
// non-deletion entries in the file. The motivation here is that in
// a stable workload, the number of deletion entries should be roughly
// equal to the number of non-deletion entries. If we compensate the
// size of deletion entries in a stable workload, the deletion
// compensation logic might introduce unwanted effet which changes the
// shape of LSM tree.
if (file_meta->num_deletions * 2 >= file_meta->num_entries) {
file_meta->compensated_file_size +=
(file_meta->num_deletions * 2 - file_meta->num_entries) *
average_value_size * kDeletionWeightOnCompaction;
}
}
}
}
}
int VersionStorageInfo::MaxInputLevel() const {
if (compaction_style_ == kCompactionStyleLevel) {
return num_levels() - 2;
}
return 0;
}
int VersionStorageInfo::MaxOutputLevel(bool allow_ingest_behind) const {
if (allow_ingest_behind) {
assert(num_levels() > 1);
return num_levels() - 2;
}
return num_levels() - 1;
}
void VersionStorageInfo::EstimateCompactionBytesNeeded(
const MutableCFOptions& mutable_cf_options) {
// Only implemented for level-based compaction
if (compaction_style_ != kCompactionStyleLevel) {
estimated_compaction_needed_bytes_ = 0;
return;
}
// Start from Level 0, if level 0 qualifies compaction to level 1,
// we estimate the size of compaction.
// Then we move on to the next level and see whether it qualifies compaction
// to the next level. The size of the level is estimated as the actual size
// on the level plus the input bytes from the previous level if there is any.
// If it exceeds, take the exceeded bytes as compaction input and add the size
// of the compaction size to tatal size.
// We keep doing it to Level 2, 3, etc, until the last level and return the
// accumulated bytes.
uint64_t bytes_compact_to_next_level = 0;
uint64_t level_size = 0;
for (auto* f : files_[0]) {
level_size += f->fd.GetFileSize();
}
// Level 0
bool level0_compact_triggered = false;
if (static_cast<int>(files_[0].size()) >=
mutable_cf_options.level0_file_num_compaction_trigger ||
level_size >= mutable_cf_options.max_bytes_for_level_base) {
level0_compact_triggered = true;
estimated_compaction_needed_bytes_ = level_size;
bytes_compact_to_next_level = level_size;
} else {
estimated_compaction_needed_bytes_ = 0;
}
// Level 1 and up.
uint64_t bytes_next_level = 0;
for (int level = base_level(); level <= MaxInputLevel(); level++) {
level_size = 0;
if (bytes_next_level > 0) {
#ifndef NDEBUG
uint64_t level_size2 = 0;
for (auto* f : files_[level]) {
level_size2 += f->fd.GetFileSize();
}
assert(level_size2 == bytes_next_level);
#endif
level_size = bytes_next_level;
bytes_next_level = 0;
} else {
for (auto* f : files_[level]) {
level_size += f->fd.GetFileSize();
}
}
if (level == base_level() && level0_compact_triggered) {
// Add base level size to compaction if level0 compaction triggered.
estimated_compaction_needed_bytes_ += level_size;
}
// Add size added by previous compaction
level_size += bytes_compact_to_next_level;
bytes_compact_to_next_level = 0;
uint64_t level_target = MaxBytesForLevel(level);
if (level_size > level_target) {
bytes_compact_to_next_level = level_size - level_target;
// Estimate the actual compaction fan-out ratio as size ratio between
// the two levels.
assert(bytes_next_level == 0);
if (level + 1 < num_levels_) {
for (auto* f : files_[level + 1]) {
bytes_next_level += f->fd.GetFileSize();
}
}
if (bytes_next_level > 0) {
assert(level_size > 0);
estimated_compaction_needed_bytes_ += static_cast<uint64_t>(
static_cast<double>(bytes_compact_to_next_level) *
(static_cast<double>(bytes_next_level) /
static_cast<double>(level_size) +
1));
}
}
}
}
namespace {
uint32_t GetExpiredTtlFilesCount(const ImmutableCFOptions& ioptions,
const MutableCFOptions& mutable_cf_options,
const std::vector<FileMetaData*>& files) {
uint32_t ttl_expired_files_count = 0;
int64_t _current_time;
auto status = ioptions.env->GetCurrentTime(&_current_time);
if (status.ok()) {
const uint64_t current_time = static_cast<uint64_t>(_current_time);
for (FileMetaData* f : files) {
if (!f->being_compacted) {
uint64_t oldest_ancester_time = f->TryGetOldestAncesterTime();
if (oldest_ancester_time != 0 &&
oldest_ancester_time < (current_time - mutable_cf_options.ttl)) {
ttl_expired_files_count++;
}
}
}
}
return ttl_expired_files_count;
}
} // anonymous namespace
void VersionStorageInfo::ComputeCompactionScore(
const ImmutableCFOptions& immutable_cf_options,
const MutableCFOptions& mutable_cf_options) {
for (int level = 0; level <= MaxInputLevel(); level++) {
double score;
if (level == 0) {
// We treat level-0 specially by bounding the number of files
// instead of number of bytes for two reasons:
//
// (1) With larger write-buffer sizes, it is nice not to do too
// many level-0 compactions.
//
// (2) The files in level-0 are merged on every read and
// therefore we wish to avoid too many files when the individual
// file size is small (perhaps because of a small write-buffer
// setting, or very high compression ratios, or lots of
// overwrites/deletions).
int num_sorted_runs = 0;
uint64_t total_size = 0;
for (auto* f : files_[level]) {
if (!f->being_compacted) {
total_size += f->compensated_file_size;
num_sorted_runs++;
}
}
if (compaction_style_ == kCompactionStyleUniversal) {
// For universal compaction, we use level0 score to indicate
// compaction score for the whole DB. Adding other levels as if
// they are L0 files.
for (int i = 1; i < num_levels(); i++) {
if (!files_[i].empty() && !files_[i][0]->being_compacted) {
num_sorted_runs++;
}
}
}
if (compaction_style_ == kCompactionStyleFIFO) {
score = static_cast<double>(total_size) /
mutable_cf_options.compaction_options_fifo.max_table_files_size;
if (mutable_cf_options.compaction_options_fifo.allow_compaction) {
score = std::max(
static_cast<double>(num_sorted_runs) /
mutable_cf_options.level0_file_num_compaction_trigger,
score);
}
if (mutable_cf_options.ttl > 0) {
score = std::max(
static_cast<double>(GetExpiredTtlFilesCount(
immutable_cf_options, mutable_cf_options, files_[level])),
score);
}
} else {
score = static_cast<double>(num_sorted_runs) /
mutable_cf_options.level0_file_num_compaction_trigger;
if (compaction_style_ == kCompactionStyleLevel && num_levels() > 1) {
// Level-based involves L0->L0 compactions that can lead to oversized
// L0 files. Take into account size as well to avoid later giant
// compactions to the base level.
score = std::max(
score, static_cast<double>(total_size) /
mutable_cf_options.max_bytes_for_level_base);
}
}
} else {
// Compute the ratio of current size to size limit.
uint64_t level_bytes_no_compacting = 0;
for (auto f : files_[level]) {
if (!f->being_compacted) {
level_bytes_no_compacting += f->compensated_file_size;
}
}
score = static_cast<double>(level_bytes_no_compacting) /
MaxBytesForLevel(level);
}
compaction_level_[level] = level;
compaction_score_[level] = score;
}
// sort all the levels based on their score. Higher scores get listed
// first. Use bubble sort because the number of entries are small.
for (int i = 0; i < num_levels() - 2; i++) {
for (int j = i + 1; j < num_levels() - 1; j++) {
if (compaction_score_[i] < compaction_score_[j]) {
double score = compaction_score_[i];
int level = compaction_level_[i];
compaction_score_[i] = compaction_score_[j];
compaction_level_[i] = compaction_level_[j];
compaction_score_[j] = score;
compaction_level_[j] = level;
}
}
}
ComputeFilesMarkedForCompaction();
ComputeBottommostFilesMarkedForCompaction();
if (mutable_cf_options.ttl > 0) {
ComputeExpiredTtlFiles(immutable_cf_options, mutable_cf_options.ttl);
}
if (mutable_cf_options.periodic_compaction_seconds > 0) {
ComputeFilesMarkedForPeriodicCompaction(
immutable_cf_options, mutable_cf_options.periodic_compaction_seconds);
}
EstimateCompactionBytesNeeded(mutable_cf_options);
}
void VersionStorageInfo::ComputeFilesMarkedForCompaction() {
files_marked_for_compaction_.clear();
int last_qualify_level = 0;
// Do not include files from the last level with data
// If table properties collector suggests a file on the last level,
// we should not move it to a new level.
for (int level = num_levels() - 1; level >= 1; level--) {
if (!files_[level].empty()) {
last_qualify_level = level - 1;
break;
}
}
for (int level = 0; level <= last_qualify_level; level++) {
for (auto* f : files_[level]) {
if (!f->being_compacted && f->marked_for_compaction) {
files_marked_for_compaction_.emplace_back(level, f);
}
}
}
}
void VersionStorageInfo::ComputeExpiredTtlFiles(
const ImmutableCFOptions& ioptions, const uint64_t ttl) {
assert(ttl > 0);
expired_ttl_files_.clear();
int64_t _current_time;
auto status = ioptions.env->GetCurrentTime(&_current_time);
if (!status.ok()) {
return;
}
const uint64_t current_time = static_cast<uint64_t>(_current_time);
for (int level = 0; level < num_levels() - 1; level++) {
for (FileMetaData* f : files_[level]) {
if (!f->being_compacted) {
uint64_t oldest_ancester_time = f->TryGetOldestAncesterTime();
if (oldest_ancester_time > 0 &&
oldest_ancester_time < (current_time - ttl)) {
expired_ttl_files_.emplace_back(level, f);
}
}
}
}
}
void VersionStorageInfo::ComputeFilesMarkedForPeriodicCompaction(
const ImmutableCFOptions& ioptions,
const uint64_t periodic_compaction_seconds) {
assert(periodic_compaction_seconds > 0);
files_marked_for_periodic_compaction_.clear();
int64_t temp_current_time;
auto status = ioptions.env->GetCurrentTime(&temp_current_time);
if (!status.ok()) {
return;
}
const uint64_t current_time = static_cast<uint64_t>(temp_current_time);
// If periodic_compaction_seconds is larger than current time, periodic
// compaction can't possibly be triggered.
if (periodic_compaction_seconds > current_time) {
return;
}
const uint64_t allowed_time_limit =
current_time - periodic_compaction_seconds;
for (int level = 0; level < num_levels(); level++) {
for (auto f : files_[level]) {
if (!f->being_compacted) {
// Compute a file's modification time in the following order:
// 1. Use file_creation_time table property if it is > 0.
// 2. Use creation_time table property if it is > 0.
// 3. Use file's mtime metadata if the above two table properties are 0.
// Don't consider the file at all if the modification time cannot be
// correctly determined based on the above conditions.
uint64_t file_modification_time = f->TryGetFileCreationTime();
if (file_modification_time == kUnknownFileCreationTime) {
file_modification_time = f->TryGetOldestAncesterTime();
}
if (file_modification_time == kUnknownOldestAncesterTime) {
auto file_path = TableFileName(ioptions.cf_paths, f->fd.GetNumber(),
f->fd.GetPathId());
status = ioptions.env->GetFileModificationTime(
file_path, &file_modification_time);
if (!status.ok()) {
ROCKS_LOG_WARN(ioptions.info_log,
"Can't get file modification time: %s: %s",
file_path.c_str(), status.ToString().c_str());
continue;
}
}
if (file_modification_time > 0 &&
file_modification_time < allowed_time_limit) {
files_marked_for_periodic_compaction_.emplace_back(level, f);
}
}
}
}
}
namespace {
// used to sort files by size
struct Fsize {
size_t index;
FileMetaData* file;
};
// Compator that is used to sort files based on their size
// In normal mode: descending size
bool CompareCompensatedSizeDescending(const Fsize& first, const Fsize& second) {
return (first.file->compensated_file_size >
second.file->compensated_file_size);
}
} // anonymous namespace
void VersionStorageInfo::AddFile(int level, FileMetaData* f, Logger* info_log) {
auto* level_files = &files_[level];
// Must not overlap
#ifndef NDEBUG
if (level > 0 && !level_files->empty() &&
internal_comparator_->Compare(
(*level_files)[level_files->size() - 1]->largest, f->smallest) >= 0) {
auto* f2 = (*level_files)[level_files->size() - 1];
if (info_log != nullptr) {
Error(info_log, "Adding new file %" PRIu64
" range (%s, %s) to level %d but overlapping "
"with existing file %" PRIu64 " %s %s",
f->fd.GetNumber(), f->smallest.DebugString(true).c_str(),
f->largest.DebugString(true).c_str(), level, f2->fd.GetNumber(),
f2->smallest.DebugString(true).c_str(),
f2->largest.DebugString(true).c_str());
LogFlush(info_log);
}
assert(false);
}
#else
(void)info_log;
#endif
f->refs++;
level_files->push_back(f);
}
// Version::PrepareApply() need to be called before calling the function, or
// following functions called:
// 1. UpdateNumNonEmptyLevels();
// 2. CalculateBaseBytes();
// 3. UpdateFilesByCompactionPri();
// 4. GenerateFileIndexer();
// 5. GenerateLevelFilesBrief();
// 6. GenerateLevel0NonOverlapping();
// 7. GenerateBottommostFiles();
void VersionStorageInfo::SetFinalized() {
finalized_ = true;
#ifndef NDEBUG
if (compaction_style_ != kCompactionStyleLevel) {
// Not level based compaction.
return;
}
assert(base_level_ < 0 || num_levels() == 1 ||
(base_level_ >= 1 && base_level_ < num_levels()));
// Verify all levels newer than base_level are empty except L0
for (int level = 1; level < base_level(); level++) {
assert(NumLevelBytes(level) == 0);
}
uint64_t max_bytes_prev_level = 0;
for (int level = base_level(); level < num_levels() - 1; level++) {
if (LevelFiles(level).size() == 0) {
continue;
}
assert(MaxBytesForLevel(level) >= max_bytes_prev_level);
max_bytes_prev_level = MaxBytesForLevel(level);
}
int num_empty_non_l0_level = 0;
for (int level = 0; level < num_levels(); level++) {
assert(LevelFiles(level).size() == 0 ||
LevelFiles(level).size() == LevelFilesBrief(level).num_files);
if (level > 0 && NumLevelBytes(level) > 0) {
num_empty_non_l0_level++;
}
if (LevelFiles(level).size() > 0) {
assert(level < num_non_empty_levels());
}
}
assert(compaction_level_.size() > 0);
assert(compaction_level_.size() == compaction_score_.size());
#endif
}
void VersionStorageInfo::UpdateNumNonEmptyLevels() {
num_non_empty_levels_ = num_levels_;
for (int i = num_levels_ - 1; i >= 0; i--) {
if (files_[i].size() != 0) {
return;
} else {
num_non_empty_levels_ = i;
}
}
}
namespace {
// Sort `temp` based on ratio of overlapping size over file size
void SortFileByOverlappingRatio(
const InternalKeyComparator& icmp, const std::vector<FileMetaData*>& files,
const std::vector<FileMetaData*>& next_level_files,
std::vector<Fsize>* temp) {
std::unordered_map<uint64_t, uint64_t> file_to_order;
auto next_level_it = next_level_files.begin();
for (auto& file : files) {
uint64_t overlapping_bytes = 0;
// Skip files in next level that is smaller than current file
while (next_level_it != next_level_files.end() &&
icmp.Compare((*next_level_it)->largest, file->smallest) < 0) {
next_level_it++;
}
while (next_level_it != next_level_files.end() &&
icmp.Compare((*next_level_it)->smallest, file->largest) < 0) {
overlapping_bytes += (*next_level_it)->fd.file_size;
if (icmp.Compare((*next_level_it)->largest, file->largest) > 0) {
// next level file cross large boundary of current file.
break;
}
next_level_it++;
}
assert(file->compensated_file_size != 0);
file_to_order[file->fd.GetNumber()] =
overlapping_bytes * 1024u / file->compensated_file_size;
}
std::sort(temp->begin(), temp->end(),
[&](const Fsize& f1, const Fsize& f2) -> bool {
return file_to_order[f1.file->fd.GetNumber()] <
file_to_order[f2.file->fd.GetNumber()];
});
}
} // namespace
void VersionStorageInfo::UpdateFilesByCompactionPri(
CompactionPri compaction_pri) {
if (compaction_style_ == kCompactionStyleNone ||
compaction_style_ == kCompactionStyleFIFO ||
compaction_style_ == kCompactionStyleUniversal) {
// don't need this
return;
}
// No need to sort the highest level because it is never compacted.
for (int level = 0; level < num_levels() - 1; level++) {
const std::vector<FileMetaData*>& files = files_[level];
auto& files_by_compaction_pri = files_by_compaction_pri_[level];
assert(files_by_compaction_pri.size() == 0);
// populate a temp vector for sorting based on size
std::vector<Fsize> temp(files.size());
for (size_t i = 0; i < files.size(); i++) {
temp[i].index = i;
temp[i].file = files[i];
}
// sort the top number_of_files_to_sort_ based on file size
size_t num = VersionStorageInfo::kNumberFilesToSort;
if (num > temp.size()) {
num = temp.size();
}
switch (compaction_pri) {
case kByCompensatedSize:
std::partial_sort(temp.begin(), temp.begin() + num, temp.end(),
CompareCompensatedSizeDescending);
break;
case kOldestLargestSeqFirst:
std::sort(temp.begin(), temp.end(),
[](const Fsize& f1, const Fsize& f2) -> bool {
return f1.file->fd.largest_seqno <
f2.file->fd.largest_seqno;
});
break;
case kOldestSmallestSeqFirst:
std::sort(temp.begin(), temp.end(),
[](const Fsize& f1, const Fsize& f2) -> bool {
return f1.file->fd.smallest_seqno <
f2.file->fd.smallest_seqno;
});
break;
case kMinOverlappingRatio:
SortFileByOverlappingRatio(*internal_comparator_, files_[level],
files_[level + 1], &temp);
break;
default:
assert(false);
}
assert(temp.size() == files.size());
// initialize files_by_compaction_pri_
for (size_t i = 0; i < temp.size(); i++) {
files_by_compaction_pri.push_back(static_cast<int>(temp[i].index));
}
next_file_to_compact_by_size_[level] = 0;
assert(files_[level].size() == files_by_compaction_pri_[level].size());
}
}
void VersionStorageInfo::GenerateLevel0NonOverlapping() {
assert(!finalized_);
level0_non_overlapping_ = true;
if (level_files_brief_.size() == 0) {
return;
}
// A copy of L0 files sorted by smallest key
std::vector<FdWithKeyRange> level0_sorted_file(
level_files_brief_[0].files,
level_files_brief_[0].files + level_files_brief_[0].num_files);
std::sort(level0_sorted_file.begin(), level0_sorted_file.end(),
[this](const FdWithKeyRange& f1, const FdWithKeyRange& f2) -> bool {
return (internal_comparator_->Compare(f1.smallest_key,
f2.smallest_key) < 0);
});
for (size_t i = 1; i < level0_sorted_file.size(); ++i) {
FdWithKeyRange& f = level0_sorted_file[i];
FdWithKeyRange& prev = level0_sorted_file[i - 1];
if (internal_comparator_->Compare(prev.largest_key, f.smallest_key) >= 0) {
level0_non_overlapping_ = false;
break;
}
}
}
void VersionStorageInfo::GenerateBottommostFiles() {
assert(!finalized_);
assert(bottommost_files_.empty());
for (size_t level = 0; level < level_files_brief_.size(); ++level) {
for (size_t file_idx = 0; file_idx < level_files_brief_[level].num_files;
++file_idx) {
const FdWithKeyRange& f = level_files_brief_[level].files[file_idx];
int l0_file_idx;
if (level == 0) {
l0_file_idx = static_cast<int>(file_idx);
} else {
l0_file_idx = -1;
}
Slice smallest_user_key = ExtractUserKey(f.smallest_key);
Slice largest_user_key = ExtractUserKey(f.largest_key);
if (!RangeMightExistAfterSortedRun(smallest_user_key, largest_user_key,
static_cast<int>(level),
l0_file_idx)) {
bottommost_files_.emplace_back(static_cast<int>(level),
f.file_metadata);
}
}
}
}
void VersionStorageInfo::UpdateOldestSnapshot(SequenceNumber seqnum) {
assert(seqnum >= oldest_snapshot_seqnum_);
oldest_snapshot_seqnum_ = seqnum;
if (oldest_snapshot_seqnum_ > bottommost_files_mark_threshold_) {
ComputeBottommostFilesMarkedForCompaction();
}
}
void VersionStorageInfo::ComputeBottommostFilesMarkedForCompaction() {
bottommost_files_marked_for_compaction_.clear();
bottommost_files_mark_threshold_ = kMaxSequenceNumber;
for (auto& level_and_file : bottommost_files_) {
if (!level_and_file.second->being_compacted &&
level_and_file.second->fd.largest_seqno != 0 &&
level_and_file.second->num_deletions > 1) {
// largest_seqno might be nonzero due to containing the final key in an
// earlier compaction, whose seqnum we didn't zero out. Multiple deletions
// ensures the file really contains deleted or overwritten keys.
if (level_and_file.second->fd.largest_seqno < oldest_snapshot_seqnum_) {
bottommost_files_marked_for_compaction_.push_back(level_and_file);
} else {
bottommost_files_mark_threshold_ =
std::min(bottommost_files_mark_threshold_,
level_and_file.second->fd.largest_seqno);
}
}
}
}
void Version::Ref() {
++refs_;
}
bool Version::Unref() {
assert(refs_ >= 1);
--refs_;
if (refs_ == 0) {
delete this;
return true;
}
return false;
}
bool VersionStorageInfo::OverlapInLevel(int level,
const Slice* smallest_user_key,
const Slice* largest_user_key) {
if (level >= num_non_empty_levels_) {
// empty level, no overlap
return false;
}
return SomeFileOverlapsRange(*internal_comparator_, (level > 0),
level_files_brief_[level], smallest_user_key,
largest_user_key);
}
// Store in "*inputs" all files in "level" that overlap [begin,end]
// If hint_index is specified, then it points to a file in the
// overlapping range.
// The file_index returns a pointer to any file in an overlapping range.
void VersionStorageInfo::GetOverlappingInputs(
int level, const InternalKey* begin, const InternalKey* end,
std::vector<FileMetaData*>* inputs, int hint_index, int* file_index,
bool expand_range, InternalKey** next_smallest) const {
if (level >= num_non_empty_levels_) {
// this level is empty, no overlapping inputs
return;
}
inputs->clear();
if (file_index) {
*file_index = -1;
}
const Comparator* user_cmp = user_comparator_;
if (level > 0) {
GetOverlappingInputsRangeBinarySearch(level, begin, end, inputs, hint_index,
file_index, false, next_smallest);
return;
}
if (next_smallest) {
// next_smallest key only makes sense for non-level 0, where files are
// non-overlapping
*next_smallest = nullptr;
}
Slice user_begin, user_end;
if (begin != nullptr) {
user_begin = begin->user_key();
}
if (end != nullptr) {
user_end = end->user_key();
}
// index stores the file index need to check.
std::list<size_t> index;
for (size_t i = 0; i < level_files_brief_[level].num_files; i++) {
index.emplace_back(i);
}
while (!index.empty()) {
bool found_overlapping_file = false;
auto iter = index.begin();
while (iter != index.end()) {
FdWithKeyRange* f = &(level_files_brief_[level].files[*iter]);
const Slice file_start = ExtractUserKey(f->smallest_key);
const Slice file_limit = ExtractUserKey(f->largest_key);
if (begin != nullptr &&
user_cmp->CompareWithoutTimestamp(file_limit, user_begin) < 0) {
// "f" is completely before specified range; skip it
iter++;
} else if (end != nullptr &&
user_cmp->CompareWithoutTimestamp(file_start, user_end) > 0) {
// "f" is completely after specified range; skip it
iter++;
} else {
// if overlap
inputs->emplace_back(files_[level][*iter]);
found_overlapping_file = true;
// record the first file index.
if (file_index && *file_index == -1) {
*file_index = static_cast<int>(*iter);
}
// the related file is overlap, erase to avoid checking again.
iter = index.erase(iter);
if (expand_range) {
if (begin != nullptr &&
user_cmp->CompareWithoutTimestamp(file_start, user_begin) < 0) {
user_begin = file_start;
}
if (end != nullptr &&
user_cmp->CompareWithoutTimestamp(file_limit, user_end) > 0) {
user_end = file_limit;
}
}
}
}
// if all the files left are not overlap, break
if (!found_overlapping_file) {
break;
}
}
}
// Store in "*inputs" files in "level" that within range [begin,end]
// Guarantee a "clean cut" boundary between the files in inputs
// and the surrounding files and the maxinum number of files.
// This will ensure that no parts of a key are lost during compaction.
// If hint_index is specified, then it points to a file in the range.
// The file_index returns a pointer to any file in an overlapping range.
void VersionStorageInfo::GetCleanInputsWithinInterval(
int level, const InternalKey* begin, const InternalKey* end,
std::vector<FileMetaData*>* inputs, int hint_index, int* file_index) const {
inputs->clear();
if (file_index) {
*file_index = -1;
}
if (level >= num_non_empty_levels_ || level == 0 ||
level_files_brief_[level].num_files == 0) {
// this level is empty, no inputs within range
// also don't support clean input interval within L0
return;
}
GetOverlappingInputsRangeBinarySearch(level, begin, end, inputs,
hint_index, file_index,
true /* within_interval */);
}
// Store in "*inputs" all files in "level" that overlap [begin,end]
// Employ binary search to find at least one file that overlaps the
// specified range. From that file, iterate backwards and
// forwards to find all overlapping files.
// if within_range is set, then only store the maximum clean inputs
// within range [begin, end]. "clean" means there is a boudnary
// between the files in "*inputs" and the surrounding files
void VersionStorageInfo::GetOverlappingInputsRangeBinarySearch(
int level, const InternalKey* begin, const InternalKey* end,
std::vector<FileMetaData*>* inputs, int hint_index, int* file_index,
bool within_interval, InternalKey** next_smallest) const {
assert(level > 0);
auto user_cmp = user_comparator_;
const FdWithKeyRange* files = level_files_brief_[level].files;
const int num_files = static_cast<int>(level_files_brief_[level].num_files);
// begin to use binary search to find lower bound
// and upper bound.
int start_index = 0;
int end_index = num_files;
if (begin != nullptr) {
// if within_interval is true, with file_key would find
// not overlapping ranges in std::lower_bound.
auto cmp = [&user_cmp, &within_interval](const FdWithKeyRange& f,
const InternalKey* k) {
auto& file_key = within_interval ? f.file_metadata->smallest
: f.file_metadata->largest;
return sstableKeyCompare(user_cmp, file_key, *k) < 0;
};
start_index = static_cast<int>(
std::lower_bound(files,
files + (hint_index == -1 ? num_files : hint_index),
begin, cmp) -
files);
if (start_index > 0 && within_interval) {
bool is_overlapping = true;
while (is_overlapping && start_index < num_files) {
auto& pre_limit = files[start_index - 1].file_metadata->largest;
auto& cur_start = files[start_index].file_metadata->smallest;
is_overlapping = sstableKeyCompare(user_cmp, pre_limit, cur_start) == 0;
start_index += is_overlapping;
}
}
}
if (end != nullptr) {
// if within_interval is true, with file_key would find
// not overlapping ranges in std::upper_bound.
auto cmp = [&user_cmp, &within_interval](const InternalKey* k,
const FdWithKeyRange& f) {
auto& file_key = within_interval ? f.file_metadata->largest
: f.file_metadata->smallest;
return sstableKeyCompare(user_cmp, *k, file_key) < 0;
};
end_index = static_cast<int>(
std::upper_bound(files + start_index, files + num_files, end, cmp) -
files);
if (end_index < num_files && within_interval) {
bool is_overlapping = true;
while (is_overlapping && end_index > start_index) {
auto& next_start = files[end_index].file_metadata->smallest;
auto& cur_limit = files[end_index - 1].file_metadata->largest;
is_overlapping =
sstableKeyCompare(user_cmp, cur_limit, next_start) == 0;
end_index -= is_overlapping;
}
}
}
assert(start_index <= end_index);
// If there were no overlapping files, return immediately.
if (start_index == end_index) {
if (next_smallest) {
*next_smallest = nullptr;
}
return;
}
assert(start_index < end_index);
// returns the index where an overlap is found
if (file_index) {
*file_index = start_index;
}
// insert overlapping files into vector
for (int i = start_index; i < end_index; i++) {
inputs->push_back(files_[level][i]);
}
if (next_smallest != nullptr) {
// Provide the next key outside the range covered by inputs
if (end_index < static_cast<int>(files_[level].size())) {
**next_smallest = files_[level][end_index]->smallest;
} else {
*next_smallest = nullptr;
}
}
}
uint64_t VersionStorageInfo::NumLevelBytes(int level) const {
assert(level >= 0);
assert(level < num_levels());
return TotalFileSize(files_[level]);
}
const char* VersionStorageInfo::LevelSummary(
LevelSummaryStorage* scratch) const {
int len = 0;
if (compaction_style_ == kCompactionStyleLevel && num_levels() > 1) {
assert(base_level_ < static_cast<int>(level_max_bytes_.size()));
if (level_multiplier_ != 0.0) {
len = snprintf(
scratch->buffer, sizeof(scratch->buffer),
"base level %d level multiplier %.2f max bytes base %" PRIu64 " ",
base_level_, level_multiplier_, level_max_bytes_[base_level_]);
}
}
len +=
snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len, "files[");
for (int i = 0; i < num_levels(); i++) {
int sz = sizeof(scratch->buffer) - len;
int ret = snprintf(scratch->buffer + len, sz, "%d ", int(files_[i].size()));
if (ret < 0 || ret >= sz) break;
len += ret;
}
if (len > 0) {
// overwrite the last space
--len;
}
len += snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len,
"] max score %.2f", compaction_score_[0]);
if (!files_marked_for_compaction_.empty()) {
snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len,
" (%" ROCKSDB_PRIszt " files need compaction)",
files_marked_for_compaction_.size());
}
return scratch->buffer;
}
const char* VersionStorageInfo::LevelFileSummary(FileSummaryStorage* scratch,
int level) const {
int len = snprintf(scratch->buffer, sizeof(scratch->buffer), "files_size[");
for (const auto& f : files_[level]) {
int sz = sizeof(scratch->buffer) - len;
char sztxt[16];
AppendHumanBytes(f->fd.GetFileSize(), sztxt, sizeof(sztxt));
int ret = snprintf(scratch->buffer + len, sz,
"#%" PRIu64 "(seq=%" PRIu64 ",sz=%s,%d) ",
f->fd.GetNumber(), f->fd.smallest_seqno, sztxt,
static_cast<int>(f->being_compacted));
if (ret < 0 || ret >= sz)
break;
len += ret;
}
// overwrite the last space (only if files_[level].size() is non-zero)
if (files_[level].size() && len > 0) {
--len;
}
snprintf(scratch->buffer + len, sizeof(scratch->buffer) - len, "]");
return scratch->buffer;
}
int64_t VersionStorageInfo::MaxNextLevelOverlappingBytes() {
uint64_t result = 0;
std::vector<FileMetaData*> overlaps;
for (int level = 1; level < num_levels() - 1; level++) {
for (const auto& f : files_[level]) {
GetOverlappingInputs(level + 1, &f->smallest, &f->largest, &overlaps);
const uint64_t sum = TotalFileSize(overlaps);
if (sum > result) {
result = sum;
}
}
}
return result;
}
uint64_t VersionStorageInfo::MaxBytesForLevel(int level) const {
// Note: the result for level zero is not really used since we set
// the level-0 compaction threshold based on number of files.
assert(level >= 0);
assert(level < static_cast<int>(level_max_bytes_.size()));
return level_max_bytes_[level];
}
void VersionStorageInfo::CalculateBaseBytes(const ImmutableCFOptions& ioptions,
const MutableCFOptions& options) {
// Special logic to set number of sorted runs.
// It is to match the previous behavior when all files are in L0.
int num_l0_count = static_cast<int>(files_[0].size());
if (compaction_style_ == kCompactionStyleUniversal) {
// For universal compaction, we use level0 score to indicate
// compaction score for the whole DB. Adding other levels as if
// they are L0 files.
for (int i = 1; i < num_levels(); i++) {
if (!files_[i].empty()) {
num_l0_count++;
}
}
}
set_l0_delay_trigger_count(num_l0_count);
level_max_bytes_.resize(ioptions.num_levels);
if (!ioptions.level_compaction_dynamic_level_bytes) {
base_level_ = (ioptions.compaction_style == kCompactionStyleLevel) ? 1 : -1;
// Calculate for static bytes base case
for (int i = 0; i < ioptions.num_levels; ++i) {
if (i == 0 && ioptions.compaction_style == kCompactionStyleUniversal) {
level_max_bytes_[i] = options.max_bytes_for_level_base;
} else if (i > 1) {
level_max_bytes_[i] = MultiplyCheckOverflow(
MultiplyCheckOverflow(level_max_bytes_[i - 1],
options.max_bytes_for_level_multiplier),
options.MaxBytesMultiplerAdditional(i - 1));
} else {
level_max_bytes_[i] = options.max_bytes_for_level_base;
}
}
} else {
uint64_t max_level_size = 0;
int first_non_empty_level = -1;
// Find size of non-L0 level of most data.
// Cannot use the size of the last level because it can be empty or less
// than previous levels after compaction.
for (int i = 1; i < num_levels_; i++) {
uint64_t total_size = 0;
for (const auto& f : files_[i]) {
total_size += f->fd.GetFileSize();
}
if (total_size > 0 && first_non_empty_level == -1) {
first_non_empty_level = i;
}
if (total_size > max_level_size) {
max_level_size = total_size;
}
}
// Prefill every level's max bytes to disallow compaction from there.
for (int i = 0; i < num_levels_; i++) {
level_max_bytes_[i] = std::numeric_limits<uint64_t>::max();
}
if (max_level_size == 0) {
// No data for L1 and up. L0 compacts to last level directly.
// No compaction from L1+ needs to be scheduled.
base_level_ = num_levels_ - 1;
} else {
uint64_t l0_size = 0;
for (const auto& f : files_[0]) {
l0_size += f->fd.GetFileSize();
}
uint64_t base_bytes_max =
std::max(options.max_bytes_for_level_base, l0_size);
uint64_t base_bytes_min = static_cast<uint64_t>(
base_bytes_max / options.max_bytes_for_level_multiplier);
// Try whether we can make last level's target size to be max_level_size
uint64_t cur_level_size = max_level_size;
for (int i = num_levels_ - 2; i >= first_non_empty_level; i--) {
// Round up after dividing
cur_level_size = static_cast<uint64_t>(
cur_level_size / options.max_bytes_for_level_multiplier);
}
// Calculate base level and its size.
uint64_t base_level_size;
if (cur_level_size <= base_bytes_min) {
// Case 1. If we make target size of last level to be max_level_size,
// target size of the first non-empty level would be smaller than
// base_bytes_min. We set it be base_bytes_min.
base_level_size = base_bytes_min + 1U;
base_level_ = first_non_empty_level;
ROCKS_LOG_INFO(ioptions.info_log,
"More existing levels in DB than needed. "
"max_bytes_for_level_multiplier may not be guaranteed.");
} else {
// Find base level (where L0 data is compacted to).
base_level_ = first_non_empty_level;
while (base_level_ > 1 && cur_level_size > base_bytes_max) {
--base_level_;
cur_level_size = static_cast<uint64_t>(
cur_level_size / options.max_bytes_for_level_multiplier);
}
if (cur_level_size > base_bytes_max) {
// Even L1 will be too large
assert(base_level_ == 1);
base_level_size = base_bytes_max;
} else {
base_level_size = cur_level_size;
}
}
level_multiplier_ = options.max_bytes_for_level_multiplier;
assert(base_level_size > 0);
if (l0_size > base_level_size &&
(l0_size > options.max_bytes_for_level_base ||
static_cast<int>(files_[0].size() / 2) >=
options.level0_file_num_compaction_trigger)) {
// We adjust the base level according to actual L0 size, and adjust
// the level multiplier accordingly, when:
// 1. the L0 size is larger than level size base, or
// 2. number of L0 files reaches twice the L0->L1 compaction trigger
// We don't do this otherwise to keep the LSM-tree structure stable
// unless the L0 compation is backlogged.
base_level_size = l0_size;
if (base_level_ == num_levels_ - 1) {
level_multiplier_ = 1.0;
} else {
level_multiplier_ = std::pow(
static_cast<double>(max_level_size) /
static_cast<double>(base_level_size),
1.0 / static_cast<double>(num_levels_ - base_level_ - 1));
}
}
uint64_t level_size = base_level_size;
for (int i = base_level_; i < num_levels_; i++) {
if (i > base_level_) {
level_size = MultiplyCheckOverflow(level_size, level_multiplier_);
}
// Don't set any level below base_bytes_max. Otherwise, the LSM can
// assume an hourglass shape where L1+ sizes are smaller than L0. This
// causes compaction scoring, which depends on level sizes, to favor L1+
// at the expense of L0, which may fill up and stall.
level_max_bytes_[i] = std::max(level_size, base_bytes_max);
}
}
}
}
uint64_t VersionStorageInfo::EstimateLiveDataSize() const {
// Estimate the live data size by adding up the size of the last level for all
// key ranges. Note: Estimate depends on the ordering of files in level 0
// because files in level 0 can be overlapping.
uint64_t size = 0;
auto ikey_lt = [this](InternalKey* x, InternalKey* y) {
return internal_comparator_->Compare(*x, *y) < 0;
};
// (Ordered) map of largest keys in non-overlapping files
std::map<InternalKey*, FileMetaData*, decltype(ikey_lt)> ranges(ikey_lt);
for (int l = num_levels_ - 1; l >= 0; l--) {
bool found_end = false;
for (auto file : files_[l]) {
// Find the first file where the largest key is larger than the smallest
// key of the current file. If this file does not overlap with the
// current file, none of the files in the map does. If there is
// no potential overlap, we can safely insert the rest of this level
// (if the level is not 0) into the map without checking again because
// the elements in the level are sorted and non-overlapping.
auto lb = (found_end && l != 0) ?
ranges.end() : ranges.lower_bound(&file->smallest);
found_end = (lb == ranges.end());
if (found_end || internal_comparator_->Compare(
file->largest, (*lb).second->smallest) < 0) {
ranges.emplace_hint(lb, &file->largest, file);
size += file->fd.file_size;
}
}
}
return size;
}
bool VersionStorageInfo::RangeMightExistAfterSortedRun(
const Slice& smallest_user_key, const Slice& largest_user_key,
int last_level, int last_l0_idx) {
assert((last_l0_idx != -1) == (last_level == 0));
// TODO(ajkr): this preserves earlier behavior where we considered an L0 file
// bottommost only if it's the oldest L0 file and there are no files on older
// levels. It'd be better to consider it bottommost if there's no overlap in
// older levels/files.
if (last_level == 0 &&
last_l0_idx != static_cast<int>(LevelFiles(0).size() - 1)) {
return true;
}
// Checks whether there are files living beyond the `last_level`. If lower
// levels have files, it checks for overlap between [`smallest_key`,
// `largest_key`] and those files. Bottomlevel optimizations can be made if
// there are no files in lower levels or if there is no overlap with the files
// in the lower levels.
for (int level = last_level + 1; level < num_levels(); level++) {
// The range is not in the bottommost level if there are files in lower
// levels when the `last_level` is 0 or if there are files in lower levels
// which overlap with [`smallest_key`, `largest_key`].
if (files_[level].size() > 0 &&
(last_level == 0 ||
OverlapInLevel(level, &smallest_user_key, &largest_user_key))) {
return true;
}
}
return false;
}
void Version::AddLiveFiles(std::vector<FileDescriptor>* live) {
for (int level = 0; level < storage_info_.num_levels(); level++) {
const std::vector<FileMetaData*>& files = storage_info_.files_[level];
for (const auto& file : files) {
live->push_back(file->fd);
}
}
}
std::string Version::DebugString(bool hex, bool print_stats) const {
std::string r;
for (int level = 0; level < storage_info_.num_levels_; level++) {
// E.g.,
// --- level 1 ---
// 17:123[1 .. 124]['a' .. 'd']
// 20:43[124 .. 128]['e' .. 'g']
//
// if print_stats=true:
// 17:123[1 .. 124]['a' .. 'd'](4096)
r.append("--- level ");
AppendNumberTo(&r, level);
r.append(" --- version# ");
AppendNumberTo(&r, version_number_);
r.append(" ---\n");
const std::vector<FileMetaData*>& files = storage_info_.files_[level];
for (size_t i = 0; i < files.size(); i++) {
r.push_back(' ');
AppendNumberTo(&r, files[i]->fd.GetNumber());
r.push_back(':');
AppendNumberTo(&r, files[i]->fd.GetFileSize());
r.append("[");
AppendNumberTo(&r, files[i]->fd.smallest_seqno);
r.append(" .. ");
AppendNumberTo(&r, files[i]->fd.largest_seqno);
r.append("]");
r.append("[");
r.append(files[i]->smallest.DebugString(hex));
r.append(" .. ");
r.append(files[i]->largest.DebugString(hex));
r.append("]");
if (files[i]->oldest_blob_file_number != kInvalidBlobFileNumber) {
r.append(" blob_file:");
AppendNumberTo(&r, files[i]->oldest_blob_file_number);
}
if (print_stats) {
r.append("(");
r.append(ToString(
files[i]->stats.num_reads_sampled.load(std::memory_order_relaxed)));
r.append(")");
}
r.append("\n");
}
}
return r;
}
// this is used to batch writes to the manifest file
struct VersionSet::ManifestWriter {
Status status;
bool done;
InstrumentedCondVar cv;
ColumnFamilyData* cfd;
const MutableCFOptions mutable_cf_options;
const autovector<VersionEdit*>& edit_list;
explicit ManifestWriter(InstrumentedMutex* mu, ColumnFamilyData* _cfd,
const MutableCFOptions& cf_options,
const autovector<VersionEdit*>& e)
: done(false),
cv(mu),
cfd(_cfd),
mutable_cf_options(cf_options),
edit_list(e) {}
};
Status AtomicGroupReadBuffer::AddEdit(VersionEdit* edit) {
assert(edit);
if (edit->is_in_atomic_group_) {
TEST_SYNC_POINT("AtomicGroupReadBuffer::AddEdit:AtomicGroup");
if (replay_buffer_.empty()) {
replay_buffer_.resize(edit->remaining_entries_ + 1);
TEST_SYNC_POINT_CALLBACK(
"AtomicGroupReadBuffer::AddEdit:FirstInAtomicGroup", edit);
}
read_edits_in_atomic_group_++;
if (read_edits_in_atomic_group_ + edit->remaining_entries_ !=
static_cast<uint32_t>(replay_buffer_.size())) {
TEST_SYNC_POINT_CALLBACK(
"AtomicGroupReadBuffer::AddEdit:IncorrectAtomicGroupSize", edit);
return Status::Corruption("corrupted atomic group");
}
replay_buffer_[read_edits_in_atomic_group_ - 1] = *edit;
if (read_edits_in_atomic_group_ == replay_buffer_.size()) {
TEST_SYNC_POINT_CALLBACK(
"AtomicGroupReadBuffer::AddEdit:LastInAtomicGroup", edit);
return Status::OK();
}
return Status::OK();
}
// A normal edit.
if (!replay_buffer().empty()) {
TEST_SYNC_POINT_CALLBACK(
"AtomicGroupReadBuffer::AddEdit:AtomicGroupMixedWithNormalEdits", edit);
return Status::Corruption("corrupted atomic group");
}
return Status::OK();
}
bool AtomicGroupReadBuffer::IsFull() const {
return read_edits_in_atomic_group_ == replay_buffer_.size();
}
bool AtomicGroupReadBuffer::IsEmpty() const { return replay_buffer_.empty(); }
void AtomicGroupReadBuffer::Clear() {
read_edits_in_atomic_group_ = 0;
replay_buffer_.clear();
}
VersionSet::VersionSet(const std::string& dbname,
const ImmutableDBOptions* _db_options,
const FileOptions& storage_options, Cache* table_cache,
WriteBufferManager* write_buffer_manager,
WriteController* write_controller,
BlockCacheTracer* const block_cache_tracer)
: column_family_set_(new ColumnFamilySet(
dbname, _db_options, storage_options, table_cache,
write_buffer_manager, write_controller, block_cache_tracer)),
env_(_db_options->env),
fs_(_db_options->fs.get()),
dbname_(dbname),
db_options_(_db_options),
next_file_number_(2),
manifest_file_number_(0), // Filled by Recover()
options_file_number_(0),
pending_manifest_file_number_(0),
last_sequence_(0),
last_allocated_sequence_(0),
last_published_sequence_(0),
prev_log_number_(0),
current_version_number_(0),
manifest_file_size_(0),
file_options_(storage_options),
block_cache_tracer_(block_cache_tracer) {}
VersionSet::~VersionSet() {
// we need to delete column_family_set_ because its destructor depends on
// VersionSet
Cache* table_cache = column_family_set_->get_table_cache();
column_family_set_.reset();
for (auto& file : obsolete_files_) {
if (file.metadata->table_reader_handle) {
table_cache->Release(file.metadata->table_reader_handle);
TableCache::Evict(table_cache, file.metadata->fd.GetNumber());
}
file.DeleteMetadata();
}
obsolete_files_.clear();
}
void VersionSet::AppendVersion(ColumnFamilyData* column_family_data,
Version* v) {
// compute new compaction score
v->storage_info()->ComputeCompactionScore(
*column_family_data->ioptions(),
*column_family_data->GetLatestMutableCFOptions());
// Mark v finalized
v->storage_info_.SetFinalized();
// Make "v" current
assert(v->refs_ == 0);
Version* current = column_family_data->current();
assert(v != current);
if (current != nullptr) {
assert(current->refs_ > 0);
current->Unref();
}
column_family_data->SetCurrent(v);
v->Ref();
// Append to linked list
v->prev_ = column_family_data->dummy_versions()->prev_;
v->next_ = column_family_data->dummy_versions();
v->prev_->next_ = v;
v->next_->prev_ = v;
}
Status VersionSet::ProcessManifestWrites(
std::deque<ManifestWriter>& writers, InstrumentedMutex* mu,
Directory* db_directory, bool new_descriptor_log,
const ColumnFamilyOptions* new_cf_options) {
assert(!writers.empty());
ManifestWriter& first_writer = writers.front();
ManifestWriter* last_writer = &first_writer;
assert(!manifest_writers_.empty());
assert(manifest_writers_.front() == &first_writer);
autovector<VersionEdit*> batch_edits;
autovector<Version*> versions;
autovector<const MutableCFOptions*> mutable_cf_options_ptrs;
std::vector<std::unique_ptr<BaseReferencedVersionBuilder>> builder_guards;
if (first_writer.edit_list.front()->IsColumnFamilyManipulation()) {
// No group commits for column family add or drop
LogAndApplyCFHelper(first_writer.edit_list.front());
batch_edits.push_back(first_writer.edit_list.front());
} else {
auto it = manifest_writers_.cbegin();
size_t group_start = std::numeric_limits<size_t>::max();
while (it != manifest_writers_.cend()) {
if ((*it)->edit_list.front()->IsColumnFamilyManipulation()) {
// no group commits for column family add or drop
break;
}
last_writer = *(it++);
assert(last_writer != nullptr);
assert(last_writer->cfd != nullptr);
if (last_writer->cfd->IsDropped()) {
// If we detect a dropped CF at this point, and the corresponding
// version edits belong to an atomic group, then we need to find out
// the preceding version edits in the same atomic group, and update
// their `remaining_entries_` member variable because we are NOT going
// to write the version edits' of dropped CF to the MANIFEST. If we
// don't update, then Recover can report corrupted atomic group because
// the `remaining_entries_` do not match.
if (!batch_edits.empty()) {
if (batch_edits.back()->is_in_atomic_group_ &&
batch_edits.back()->remaining_entries_ > 0) {
assert(group_start < batch_edits.size());
const auto& edit_list = last_writer->edit_list;
size_t k = 0;
while (k < edit_list.size()) {
if (!edit_list[k]->is_in_atomic_group_) {
break;
} else if (edit_list[k]->remaining_entries_ == 0) {
++k;
break;
}
++k;
}
for (auto i = group_start; i < batch_edits.size(); ++i) {
assert(static_cast<uint32_t>(k) <=
batch_edits.back()->remaining_entries_);
batch_edits[i]->remaining_entries_ -= static_cast<uint32_t>(k);
}
}
}
continue;
}
// We do a linear search on versions because versions is small.
// TODO(yanqin) maybe consider unordered_map
Version* version = nullptr;
VersionBuilder* builder = nullptr;
for (int i = 0; i != static_cast<int>(versions.size()); ++i) {
uint32_t cf_id = last_writer->cfd->GetID();
if (versions[i]->cfd()->GetID() == cf_id) {
version = versions[i];
assert(!builder_guards.empty() &&
builder_guards.size() == versions.size());
builder = builder_guards[i]->version_builder();
TEST_SYNC_POINT_CALLBACK(
"VersionSet::ProcessManifestWrites:SameColumnFamily", &cf_id);
break;
}
}
if (version == nullptr) {
version = new Version(last_writer->cfd, this, file_options_,
last_writer->mutable_cf_options,
current_version_number_++);
versions.push_back(version);
mutable_cf_options_ptrs.push_back(&last_writer->mutable_cf_options);
builder_guards.emplace_back(
new BaseReferencedVersionBuilder(last_writer->cfd));
builder = builder_guards.back()->version_builder();
}
assert(builder != nullptr); // make checker happy
for (const auto& e : last_writer->edit_list) {
if (e->is_in_atomic_group_) {
if (batch_edits.empty() || !batch_edits.back()->is_in_atomic_group_ ||
(batch_edits.back()->is_in_atomic_group_ &&
batch_edits.back()->remaining_entries_ == 0)) {
group_start = batch_edits.size();
}
} else if (group_start != std::numeric_limits<size_t>::max()) {
group_start = std::numeric_limits<size_t>::max();
}
Status s = LogAndApplyHelper(last_writer->cfd, builder, e, mu);
if (!s.ok()) {
// free up the allocated memory
for (auto v : versions) {
delete v;
}
return s;
}
batch_edits.push_back(e);
}
}
for (int i = 0; i < static_cast<int>(versions.size()); ++i) {
assert(!builder_guards.empty() &&
builder_guards.size() == versions.size());
auto* builder = builder_guards[i]->version_builder();
Status s = builder->SaveTo(versions[i]->storage_info());
if (!s.ok()) {
// free up the allocated memory
for (auto v : versions) {
delete v;
}
return s;
}
}
}
#ifndef NDEBUG
// Verify that version edits of atomic groups have correct
// remaining_entries_.
size_t k = 0;
while (k < batch_edits.size()) {
while (k < batch_edits.size() && !batch_edits[k]->is_in_atomic_group_) {
++k;
}
if (k == batch_edits.size()) {
break;
}
size_t i = k;
while (i < batch_edits.size()) {
if (!batch_edits[i]->is_in_atomic_group_) {
break;
}
assert(i - k + batch_edits[i]->remaining_entries_ ==
batch_edits[k]->remaining_entries_);
if (batch_edits[i]->remaining_entries_ == 0) {
++i;
break;
}
++i;
}
assert(batch_edits[i - 1]->is_in_atomic_group_);
assert(0 == batch_edits[i - 1]->remaining_entries_);
std::vector<VersionEdit*> tmp;
for (size_t j = k; j != i; ++j) {
tmp.emplace_back(batch_edits[j]);
}
TEST_SYNC_POINT_CALLBACK(
"VersionSet::ProcessManifestWrites:CheckOneAtomicGroup", &tmp);
k = i;
}
#endif // NDEBUG
uint64_t new_manifest_file_size = 0;
Status s;
assert(pending_manifest_file_number_ == 0);
if (!descriptor_log_ ||
manifest_file_size_ > db_options_->max_manifest_file_size) {
TEST_SYNC_POINT("VersionSet::ProcessManifestWrites:BeforeNewManifest");
new_descriptor_log = true;
} else {
pending_manifest_file_number_ = manifest_file_number_;
}
// Local cached copy of state variable(s). WriteCurrentStateToManifest()
// reads its content after releasing db mutex to avoid race with
// SwitchMemtable().
std::unordered_map<uint32_t, MutableCFState> curr_state;
if (new_descriptor_log) {
pending_manifest_file_number_ = NewFileNumber();
batch_edits.back()->SetNextFile(next_file_number_.load());
// if we are writing out new snapshot make sure to persist max column
// family.
if (column_family_set_->GetMaxColumnFamily() > 0) {
first_writer.edit_list.front()->SetMaxColumnFamily(
column_family_set_->GetMaxColumnFamily());
}
for (const auto* cfd : *column_family_set_) {
assert(curr_state.find(cfd->GetID()) == curr_state.end());
curr_state[cfd->GetID()] = {cfd->GetLogNumber()};
}
}
{
FileOptions opt_file_opts = fs_->OptimizeForManifestWrite(file_options_);
mu->Unlock();
TEST_SYNC_POINT("VersionSet::LogAndApply:WriteManifest");
if (!first_writer.edit_list.front()->IsColumnFamilyManipulation()) {
for (int i = 0; i < static_cast<int>(versions.size()); ++i) {
assert(!builder_guards.empty() &&
builder_guards.size() == versions.size());
assert(!mutable_cf_options_ptrs.empty() &&
builder_guards.size() == versions.size());
ColumnFamilyData* cfd = versions[i]->cfd_;
s = builder_guards[i]->version_builder()->LoadTableHandlers(
cfd->internal_stats(), cfd->ioptions()->optimize_filters_for_hits,
true /* prefetch_index_and_filter_in_cache */,
false /* is_initial_load */,
mutable_cf_options_ptrs[i]->prefix_extractor.get());
if (!s.ok()) {
if (db_options_->paranoid_checks) {
break;
}
s = Status::OK();
}
}
}
if (s.ok() && new_descriptor_log) {
// This is fine because everything inside of this block is serialized --
// only one thread can be here at the same time
// create new manifest file
ROCKS_LOG_INFO(db_options_->info_log, "Creating manifest %" PRIu64 "\n",
pending_manifest_file_number_);
std::string descriptor_fname =
DescriptorFileName(dbname_, pending_manifest_file_number_);
std::unique_ptr<FSWritableFile> descriptor_file;
s = NewWritableFile(fs_, descriptor_fname, &descriptor_file,
opt_file_opts);
if (s.ok()) {
descriptor_file->SetPreallocationBlockSize(
db_options_->manifest_preallocation_size);
std::unique_ptr<WritableFileWriter> file_writer(new WritableFileWriter(
std::move(descriptor_file), descriptor_fname, opt_file_opts, env_,
nullptr, db_options_->listeners));
descriptor_log_.reset(
new log::Writer(std::move(file_writer), 0, false));
s = WriteCurrentStateToManifest(curr_state, descriptor_log_.get());
}
}
if (s.ok()) {
if (!first_writer.edit_list.front()->IsColumnFamilyManipulation()) {
for (int i = 0; i < static_cast<int>(versions.size()); ++i) {
versions[i]->PrepareApply(*mutable_cf_options_ptrs[i], true);
}
}
// Write new records to MANIFEST log
#ifndef NDEBUG
size_t idx = 0;
#endif
for (auto& e : batch_edits) {
std::string record;
if (!e->EncodeTo(&record)) {
s = Status::Corruption("Unable to encode VersionEdit:" +
e->DebugString(true));
break;
}
TEST_KILL_RANDOM("VersionSet::LogAndApply:BeforeAddRecord",
rocksdb_kill_odds * REDUCE_ODDS2);
#ifndef NDEBUG
if (batch_edits.size() > 1 && batch_edits.size() - 1 == idx) {
TEST_SYNC_POINT_CALLBACK(
"VersionSet::ProcessManifestWrites:BeforeWriteLastVersionEdit:0",
nullptr);
TEST_SYNC_POINT(
"VersionSet::ProcessManifestWrites:BeforeWriteLastVersionEdit:1");
}
++idx;
#endif /* !NDEBUG */
s = descriptor_log_->AddRecord(record);
if (!s.ok()) {
break;
}
}
if (s.ok()) {
s = SyncManifest(env_, db_options_, descriptor_log_->file());
}
if (!s.ok()) {
ROCKS_LOG_ERROR(db_options_->info_log, "MANIFEST write %s\n",
s.ToString().c_str());
}
}
// If we just created a new descriptor file, install it by writing a
// new CURRENT file that points to it.
if (s.ok() && new_descriptor_log) {
s = SetCurrentFile(env_, dbname_, pending_manifest_file_number_,
db_directory);
TEST_SYNC_POINT("VersionSet::ProcessManifestWrites:AfterNewManifest");
}
if (s.ok()) {
// find offset in manifest file where this version is stored.
new_manifest_file_size = descriptor_log_->file()->GetFileSize();
}
if (first_writer.edit_list.front()->is_column_family_drop_) {
TEST_SYNC_POINT("VersionSet::LogAndApply::ColumnFamilyDrop:0");
TEST_SYNC_POINT("VersionSet::LogAndApply::ColumnFamilyDrop:1");
TEST_SYNC_POINT("VersionSet::LogAndApply::ColumnFamilyDrop:2");
}
LogFlush(db_options_->info_log);
TEST_SYNC_POINT("VersionSet::LogAndApply:WriteManifestDone");
mu->Lock();
}
// Append the old manifest file to the obsolete_manifest_ list to be deleted
// by PurgeObsoleteFiles later.
if (s.ok() && new_descriptor_log) {
obsolete_manifests_.emplace_back(
DescriptorFileName("", manifest_file_number_));
}
// Install the new versions
if (s.ok()) {
if (first_writer.edit_list.front()->is_column_family_add_) {
assert(batch_edits.size() == 1);
assert(new_cf_options != nullptr);
CreateColumnFamily(*new_cf_options, first_writer.edit_list.front());
} else if (first_writer.edit_list.front()->is_column_family_drop_) {
assert(batch_edits.size() == 1);
first_writer.cfd->SetDropped();
first_writer.cfd->UnrefAndTryDelete();
} else {
// Each version in versions corresponds to a column family.
// For each column family, update its log number indicating that logs
// with number smaller than this should be ignored.
for (const auto version : versions) {
uint64_t max_log_number_in_batch = 0;
uint32_t cf_id = version->cfd_->GetID();
for (const auto& e : batch_edits) {
if (e->has_log_number_ && e->column_family_ == cf_id) {
max_log_number_in_batch =
std::max(max_log_number_in_batch, e->log_number_);
}
}
if (max_log_number_in_batch != 0) {
assert(version->cfd_->GetLogNumber() <= max_log_number_in_batch);
version->cfd_->SetLogNumber(max_log_number_in_batch);
}
}
uint64_t last_min_log_number_to_keep = 0;
for (auto& e : batch_edits) {
if (e->has_min_log_number_to_keep_) {
last_min_log_number_to_keep =
std::max(last_min_log_number_to_keep, e->min_log_number_to_keep_);
}
}
if (last_min_log_number_to_keep != 0) {
// Should only be set in 2PC mode.
MarkMinLogNumberToKeep2PC(last_min_log_number_to_keep);
}
for (int i = 0; i < static_cast<int>(versions.size()); ++i) {
ColumnFamilyData* cfd = versions[i]->cfd_;
AppendVersion(cfd, versions[i]);
}
}
manifest_file_number_ = pending_manifest_file_number_;
manifest_file_size_ = new_manifest_file_size;
prev_log_number_ = first_writer.edit_list.front()->prev_log_number_;
} else {
std::string version_edits;
for (auto& e : batch_edits) {
version_edits += ("\n" + e->DebugString(true));
}
ROCKS_LOG_ERROR(db_options_->info_log,
"Error in committing version edit to MANIFEST: %s",
version_edits.c_str());
for (auto v : versions) {
delete v;
}
// If manifest append failed for whatever reason, the file could be
// corrupted. So we need to force the next version update to start a
// new manifest file.
descriptor_log_.reset();
if (new_descriptor_log) {
ROCKS_LOG_INFO(db_options_->info_log,
"Deleting manifest %" PRIu64 " current manifest %" PRIu64
"\n",
manifest_file_number_, pending_manifest_file_number_);
env_->DeleteFile(
DescriptorFileName(dbname_, pending_manifest_file_number_));
}
}
pending_manifest_file_number_ = 0;
// wake up all the waiting writers
while (true) {
ManifestWriter* ready = manifest_writers_.front();
manifest_writers_.pop_front();
bool need_signal = true;
for (const auto& w : writers) {
if (&w == ready) {
need_signal = false;
break;
}
}
ready->status = s;
ready->done = true;
if (need_signal) {
ready->cv.Signal();
}
if (ready == last_writer) {
break;
}
}
if (!manifest_writers_.empty()) {
manifest_writers_.front()->cv.Signal();
}
return s;
}
// 'datas' is gramatically incorrect. We still use this notation to indicate
// that this variable represents a collection of column_family_data.
Status VersionSet::LogAndApply(
const autovector<ColumnFamilyData*>& column_family_datas,
const autovector<const MutableCFOptions*>& mutable_cf_options_list,
const autovector<autovector<VersionEdit*>>& edit_lists,
InstrumentedMutex* mu, Directory* db_directory, bool new_descriptor_log,
const ColumnFamilyOptions* new_cf_options) {
mu->AssertHeld();
int num_edits = 0;
for (const auto& elist : edit_lists) {
num_edits += static_cast<int>(elist.size());
}
if (num_edits == 0) {
return Status::OK();
} else if (num_edits > 1) {
#ifndef NDEBUG
for (const auto& edit_list : edit_lists) {
for (const auto& edit : edit_list) {
assert(!edit->IsColumnFamilyManipulation());
}
}
#endif /* ! NDEBUG */
}
int num_cfds = static_cast<int>(column_family_datas.size());
if (num_cfds == 1 && column_family_datas[0] == nullptr) {
assert(edit_lists.size() == 1 && edit_lists[0].size() == 1);
assert(edit_lists[0][0]->is_column_family_add_);
assert(new_cf_options != nullptr);
}
std::deque<ManifestWriter> writers;
if (num_cfds > 0) {
assert(static_cast<size_t>(num_cfds) == mutable_cf_options_list.size());
assert(static_cast<size_t>(num_cfds) == edit_lists.size());
}
for (int i = 0; i < num_cfds; ++i) {
writers.emplace_back(mu, column_family_datas[i],
*mutable_cf_options_list[i], edit_lists[i]);
manifest_writers_.push_back(&writers[i]);
}
assert(!writers.empty());
ManifestWriter& first_writer = writers.front();
while (!first_writer.done && &first_writer != manifest_writers_.front()) {
first_writer.cv.Wait();
}
if (first_writer.done) {
// All non-CF-manipulation operations can be grouped together and committed
// to MANIFEST. They should all have finished. The status code is stored in
// the first manifest writer.
#ifndef NDEBUG
for (const auto& writer : writers) {
assert(writer.done);
}
#endif /* !NDEBUG */
return first_writer.status;
}
int num_undropped_cfds = 0;
for (auto cfd : column_family_datas) {
// if cfd == nullptr, it is a column family add.
if (cfd == nullptr || !cfd->IsDropped()) {
++num_undropped_cfds;
}
}
if (0 == num_undropped_cfds) {
for (int i = 0; i != num_cfds; ++i) {
manifest_writers_.pop_front();
}
// Notify new head of manifest write queue.
if (!manifest_writers_.empty()) {
manifest_writers_.front()->cv.Signal();
}
return Status::ColumnFamilyDropped();
}
return ProcessManifestWrites(writers, mu, db_directory, new_descriptor_log,
new_cf_options);
}
void VersionSet::LogAndApplyCFHelper(VersionEdit* edit) {
assert(edit->IsColumnFamilyManipulation());
edit->SetNextFile(next_file_number_.load());
// The log might have data that is not visible to memtbale and hence have not
// updated the last_sequence_ yet. It is also possible that the log has is
// expecting some new data that is not written yet. Since LastSequence is an
// upper bound on the sequence, it is ok to record
// last_allocated_sequence_ as the last sequence.
edit->SetLastSequence(db_options_->two_write_queues ? last_allocated_sequence_
: last_sequence_);
if (edit->is_column_family_drop_) {
// if we drop column family, we have to make sure to save max column family,
// so that we don't reuse existing ID
edit->SetMaxColumnFamily(column_family_set_->GetMaxColumnFamily());
}
}
Status VersionSet::LogAndApplyHelper(ColumnFamilyData* cfd,
VersionBuilder* builder, VersionEdit* edit,
InstrumentedMutex* mu) {
#ifdef NDEBUG
(void)cfd;
#endif
mu->AssertHeld();
assert(!edit->IsColumnFamilyManipulation());
if (edit->has_log_number_) {
assert(edit->log_number_ >= cfd->GetLogNumber());
assert(edit->log_number_ < next_file_number_.load());
}
if (!edit->has_prev_log_number_) {
edit->SetPrevLogNumber(prev_log_number_);
}
edit->SetNextFile(next_file_number_.load());
// The log might have data that is not visible to memtbale and hence have not
// updated the last_sequence_ yet. It is also possible that the log has is
// expecting some new data that is not written yet. Since LastSequence is an
// upper bound on the sequence, it is ok to record
// last_allocated_sequence_ as the last sequence.
edit->SetLastSequence(db_options_->two_write_queues ? last_allocated_sequence_
: last_sequence_);
Status s = builder->Apply(edit);
return s;
}
Status VersionSet::ApplyOneVersionEditToBuilder(
VersionEdit& edit,
const std::unordered_map<std::string, ColumnFamilyOptions>& name_to_options,
std::unordered_map<int, std::string>& column_families_not_found,
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>&
builders,
VersionEditParams* version_edit_params) {
// Not found means that user didn't supply that column
// family option AND we encountered column family add
// record. Once we encounter column family drop record,
// we will delete the column family from
// column_families_not_found.
bool cf_in_not_found = (column_families_not_found.find(edit.column_family_) !=
column_families_not_found.end());
// in builders means that user supplied that column family
// option AND that we encountered column family add record
bool cf_in_builders = builders.find(edit.column_family_) != builders.end();
// they can't both be true
assert(!(cf_in_not_found && cf_in_builders));
ColumnFamilyData* cfd = nullptr;
if (edit.is_column_family_add_) {
if (cf_in_builders || cf_in_not_found) {
return Status::Corruption(
"Manifest adding the same column family twice: " +
edit.column_family_name_);
}
auto cf_options = name_to_options.find(edit.column_family_name_);
// implicitly add persistent_stats column family without requiring user
// to specify
bool is_persistent_stats_column_family =
edit.column_family_name_.compare(kPersistentStatsColumnFamilyName) == 0;
if (cf_options == name_to_options.end() &&
!is_persistent_stats_column_family) {
column_families_not_found.insert(
{edit.column_family_, edit.column_family_name_});
} else {
// recover persistent_stats CF from a DB that already contains it
if (is_persistent_stats_column_family) {
ColumnFamilyOptions cfo;
OptimizeForPersistentStats(&cfo);
cfd = CreateColumnFamily(cfo, &edit);
} else {
cfd = CreateColumnFamily(cf_options->second, &edit);
}
cfd->set_initialized();
builders.insert(std::make_pair(
edit.column_family_, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(cfd))));
}
} else if (edit.is_column_family_drop_) {
if (cf_in_builders) {
auto builder = builders.find(edit.column_family_);
assert(builder != builders.end());
builders.erase(builder);
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
assert(cfd != nullptr);
if (cfd->UnrefAndTryDelete()) {
cfd = nullptr;
} else {
// who else can have reference to cfd!?
assert(false);
}
} else if (cf_in_not_found) {
column_families_not_found.erase(edit.column_family_);
} else {
return Status::Corruption(
"Manifest - dropping non-existing column family");
}
} else if (!cf_in_not_found) {
if (!cf_in_builders) {
return Status::Corruption(
"Manifest record referencing unknown column family");
}
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
// this should never happen since cf_in_builders is true
assert(cfd != nullptr);
// if it is not column family add or column family drop,
// then it's a file add/delete, which should be forwarded
// to builder
auto builder = builders.find(edit.column_family_);
assert(builder != builders.end());
Status s = builder->second->version_builder()->Apply(&edit);
if (!s.ok()) {
return s;
}
}
return ExtractInfoFromVersionEdit(cfd, edit, version_edit_params);
}
Status VersionSet::ExtractInfoFromVersionEdit(
ColumnFamilyData* cfd, const VersionEdit& from_edit,
VersionEditParams* version_edit_params) {
if (cfd != nullptr) {
if (from_edit.has_db_id_) {
version_edit_params->SetDBId(from_edit.db_id_);
}
if (from_edit.has_log_number_) {
if (cfd->GetLogNumber() > from_edit.log_number_) {
ROCKS_LOG_WARN(
db_options_->info_log,
"MANIFEST corruption detected, but ignored - Log numbers in "
"records NOT monotonically increasing");
} else {
cfd->SetLogNumber(from_edit.log_number_);
version_edit_params->SetLogNumber(from_edit.log_number_);
}
}
if (from_edit.has_comparator_ &&
from_edit.comparator_ != cfd->user_comparator()->Name()) {
return Status::InvalidArgument(
cfd->user_comparator()->Name(),
"does not match existing comparator " + from_edit.comparator_);
}
}
if (from_edit.has_prev_log_number_) {
version_edit_params->SetPrevLogNumber(from_edit.prev_log_number_);
}
if (from_edit.has_next_file_number_) {
version_edit_params->SetNextFile(from_edit.next_file_number_);
}
if (from_edit.has_max_column_family_) {
version_edit_params->SetMaxColumnFamily(from_edit.max_column_family_);
}
if (from_edit.has_min_log_number_to_keep_) {
version_edit_params->min_log_number_to_keep_ =
std::max(version_edit_params->min_log_number_to_keep_,
from_edit.min_log_number_to_keep_);
}
if (from_edit.has_last_sequence_) {
version_edit_params->SetLastSequence(from_edit.last_sequence_);
}
return Status::OK();
}
Status VersionSet::GetCurrentManifestPath(const std::string& dbname,
FileSystem* fs,
std::string* manifest_path,
uint64_t* manifest_file_number) {
assert(fs != nullptr);
assert(manifest_path != nullptr);
assert(manifest_file_number != nullptr);
std::string fname;
Status s = ReadFileToString(fs, CurrentFileName(dbname), &fname);
if (!s.ok()) {
return s;
}
if (fname.empty() || fname.back() != '\n') {
return Status::Corruption("CURRENT file does not end with newline");
}
// remove the trailing '\n'
fname.resize(fname.size() - 1);
FileType type;
bool parse_ok = ParseFileName(fname, manifest_file_number, &type);
if (!parse_ok || type != kDescriptorFile) {
return Status::Corruption("CURRENT file corrupted");
}
*manifest_path = dbname;
if (dbname.back() != '/') {
manifest_path->push_back('/');
}
*manifest_path += fname;
return Status::OK();
}
Status VersionSet::ReadAndRecover(
log::Reader* reader, AtomicGroupReadBuffer* read_buffer,
const std::unordered_map<std::string, ColumnFamilyOptions>& name_to_options,
std::unordered_map<int, std::string>& column_families_not_found,
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>&
builders,
VersionEditParams* version_edit_params, std::string* db_id) {
assert(reader != nullptr);
assert(read_buffer != nullptr);
Status s;
Slice record;
std::string scratch;
size_t recovered_edits = 0;
while (reader->ReadRecord(&record, &scratch) && s.ok()) {
VersionEdit edit;
s = edit.DecodeFrom(record);
if (!s.ok()) {
break;
}
if (edit.has_db_id_) {
db_id_ = edit.GetDbId();
if (db_id != nullptr) {
db_id->assign(edit.GetDbId());
}
}
s = read_buffer->AddEdit(&edit);
if (!s.ok()) {
break;
}
if (edit.is_in_atomic_group_) {
if (read_buffer->IsFull()) {
// Apply edits in an atomic group when we have read all edits in the
// group.
for (auto& e : read_buffer->replay_buffer()) {
s = ApplyOneVersionEditToBuilder(e, name_to_options,
column_families_not_found, builders,
version_edit_params);
if (!s.ok()) {
break;
}
recovered_edits++;
}
if (!s.ok()) {
break;
}
read_buffer->Clear();
}
} else {
// Apply a normal edit immediately.
s = ApplyOneVersionEditToBuilder(edit, name_to_options,
column_families_not_found, builders,
version_edit_params);
if (s.ok()) {
recovered_edits++;
}
}
}
if (!s.ok()) {
// Clear the buffer if we fail to decode/apply an edit.
read_buffer->Clear();
}
TEST_SYNC_POINT_CALLBACK("VersionSet::ReadAndRecover:RecoveredEdits",
&recovered_edits);
return s;
}
Status VersionSet::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families, bool read_only,
std::string* db_id) {
std::unordered_map<std::string, ColumnFamilyOptions> cf_name_to_options;
for (const auto& cf : column_families) {
cf_name_to_options.emplace(cf.name, cf.options);
}
// keeps track of column families in manifest that were not found in
// column families parameters. if those column families are not dropped
// by subsequent manifest records, Recover() will return failure status
std::unordered_map<int, std::string> column_families_not_found;
// Read "CURRENT" file, which contains a pointer to the current manifest file
std::string manifest_path;
Status s = GetCurrentManifestPath(dbname_, fs_, &manifest_path,
&manifest_file_number_);
if (!s.ok()) {
return s;
}
ROCKS_LOG_INFO(db_options_->info_log, "Recovering from manifest file: %s\n",
manifest_path.c_str());
std::unique_ptr<SequentialFileReader> manifest_file_reader;
{
std::unique_ptr<FSSequentialFile> manifest_file;
s = fs_->NewSequentialFile(manifest_path,
fs_->OptimizeForManifestRead(file_options_),
&manifest_file, nullptr);
if (!s.ok()) {
return s;
}
manifest_file_reader.reset(
new SequentialFileReader(std::move(manifest_file), manifest_path,
db_options_->log_readahead_size));
}
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
builders;
// add default column family
auto default_cf_iter = cf_name_to_options.find(kDefaultColumnFamilyName);
if (default_cf_iter == cf_name_to_options.end()) {
return Status::InvalidArgument("Default column family not specified");
}
VersionEdit default_cf_edit;
default_cf_edit.AddColumnFamily(kDefaultColumnFamilyName);
default_cf_edit.SetColumnFamily(0);
ColumnFamilyData* default_cfd =
CreateColumnFamily(default_cf_iter->second, &default_cf_edit);
// In recovery, nobody else can access it, so it's fine to set it to be
// initialized earlier.
default_cfd->set_initialized();
builders.insert(
std::make_pair(0, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(default_cfd))));
uint64_t current_manifest_file_size = 0;
VersionEditParams version_edit_params;
{
VersionSet::LogReporter reporter;
reporter.status = &s;
log::Reader reader(nullptr, std::move(manifest_file_reader), &reporter,
true /* checksum */, 0 /* log_number */);
Slice record;
std::string scratch;
AtomicGroupReadBuffer read_buffer;
s = ReadAndRecover(&reader, &read_buffer, cf_name_to_options,
column_families_not_found, builders,
&version_edit_params, db_id);
current_manifest_file_size = reader.GetReadOffset();
assert(current_manifest_file_size != 0);
}
if (s.ok()) {
if (!version_edit_params.has_next_file_number_) {
s = Status::Corruption("no meta-nextfile entry in descriptor");
} else if (!version_edit_params.has_log_number_) {
s = Status::Corruption("no meta-lognumber entry in descriptor");
} else if (!version_edit_params.has_last_sequence_) {
s = Status::Corruption("no last-sequence-number entry in descriptor");
}
if (!version_edit_params.has_prev_log_number_) {
version_edit_params.SetPrevLogNumber(0);
}
column_family_set_->UpdateMaxColumnFamily(
version_edit_params.max_column_family_);
// When reading DB generated using old release, min_log_number_to_keep=0.
// All log files will be scanned for potential prepare entries.
MarkMinLogNumberToKeep2PC(version_edit_params.min_log_number_to_keep_);
MarkFileNumberUsed(version_edit_params.prev_log_number_);
MarkFileNumberUsed(version_edit_params.log_number_);
}
// there were some column families in the MANIFEST that weren't specified
// in the argument. This is OK in read_only mode
if (read_only == false && !column_families_not_found.empty()) {
std::string list_of_not_found;
for (const auto& cf : column_families_not_found) {
list_of_not_found += ", " + cf.second;
}
list_of_not_found = list_of_not_found.substr(2);
s = Status::InvalidArgument(
"You have to open all column families. Column families not opened: " +
list_of_not_found);
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
assert(builders.count(cfd->GetID()) > 0);
auto* builder = builders[cfd->GetID()]->version_builder();
if (!builder->CheckConsistencyForNumLevels()) {
s = Status::InvalidArgument(
"db has more levels than options.num_levels");
break;
}
}
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
if (read_only) {
cfd->table_cache()->SetTablesAreImmortal();
}
assert(cfd->initialized());
auto builders_iter = builders.find(cfd->GetID());
assert(builders_iter != builders.end());
auto builder = builders_iter->second->version_builder();
// unlimited table cache. Pre-load table handle now.
// Need to do it out of the mutex.
s = builder->LoadTableHandlers(
cfd->internal_stats(), db_options_->max_file_opening_threads,
false /* prefetch_index_and_filter_in_cache */,
true /* is_initial_load */,
cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
if (!s.ok()) {
if (db_options_->paranoid_checks) {
return s;
}
s = Status::OK();
}
Version* v = new Version(cfd, this, file_options_,
*cfd->GetLatestMutableCFOptions(),
current_version_number_++);
builder->SaveTo(v->storage_info());
// Install recovered version
v->PrepareApply(*cfd->GetLatestMutableCFOptions(),
!(db_options_->skip_stats_update_on_db_open));
AppendVersion(cfd, v);
}
manifest_file_size_ = current_manifest_file_size;
next_file_number_.store(version_edit_params.next_file_number_ + 1);
last_allocated_sequence_ = version_edit_params.last_sequence_;
last_published_sequence_ = version_edit_params.last_sequence_;
last_sequence_ = version_edit_params.last_sequence_;
prev_log_number_ = version_edit_params.prev_log_number_;
ROCKS_LOG_INFO(
db_options_->info_log,
"Recovered from manifest file:%s succeeded,"
"manifest_file_number is %" PRIu64 ", next_file_number is %" PRIu64
", last_sequence is %" PRIu64 ", log_number is %" PRIu64
",prev_log_number is %" PRIu64 ",max_column_family is %" PRIu32
",min_log_number_to_keep is %" PRIu64 "\n",
manifest_path.c_str(), manifest_file_number_, next_file_number_.load(),
last_sequence_.load(), version_edit_params.log_number_,
prev_log_number_, column_family_set_->GetMaxColumnFamily(),
min_log_number_to_keep_2pc());
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
ROCKS_LOG_INFO(db_options_->info_log,
"Column family [%s] (ID %" PRIu32
"), log number is %" PRIu64 "\n",
cfd->GetName().c_str(), cfd->GetID(), cfd->GetLogNumber());
}
}
return s;
}
Status VersionSet::ListColumnFamilies(std::vector<std::string>* column_families,
const std::string& dbname,
FileSystem* fs) {
// these are just for performance reasons, not correcntes,
// so we're fine using the defaults
FileOptions soptions;
// Read "CURRENT" file, which contains a pointer to the current manifest file
std::string manifest_path;
uint64_t manifest_file_number;
Status s =
GetCurrentManifestPath(dbname, fs, &manifest_path, &manifest_file_number);
if (!s.ok()) {
return s;
}
std::unique_ptr<SequentialFileReader> file_reader;
{
std::unique_ptr<FSSequentialFile> file;
s = fs->NewSequentialFile(manifest_path, soptions, &file, nullptr);
if (!s.ok()) {
return s;
}
file_reader.reset(new SequentialFileReader(std::move(file), manifest_path));
}
std::map<uint32_t, std::string> column_family_names;
// default column family is always implicitly there
column_family_names.insert({0, kDefaultColumnFamilyName});
VersionSet::LogReporter reporter;
reporter.status = &s;
log::Reader reader(nullptr, std::move(file_reader), &reporter,
true /* checksum */, 0 /* log_number */);
Slice record;
std::string scratch;
while (reader.ReadRecord(&record, &scratch) && s.ok()) {
VersionEdit edit;
s = edit.DecodeFrom(record);
if (!s.ok()) {
break;
}
if (edit.is_column_family_add_) {
if (column_family_names.find(edit.column_family_) !=
column_family_names.end()) {
s = Status::Corruption("Manifest adding the same column family twice");
break;
}
column_family_names.insert(
{edit.column_family_, edit.column_family_name_});
} else if (edit.is_column_family_drop_) {
if (column_family_names.find(edit.column_family_) ==
column_family_names.end()) {
s = Status::Corruption(
"Manifest - dropping non-existing column family");
break;
}
column_family_names.erase(edit.column_family_);
}
}
column_families->clear();
if (s.ok()) {
for (const auto& iter : column_family_names) {
column_families->push_back(iter.second);
}
}
return s;
}
#ifndef ROCKSDB_LITE
Status VersionSet::ReduceNumberOfLevels(const std::string& dbname,
const Options* options,
const FileOptions& file_options,
int new_levels) {
if (new_levels <= 1) {
return Status::InvalidArgument(
"Number of levels needs to be bigger than 1");
}
ImmutableDBOptions db_options(*options);
ColumnFamilyOptions cf_options(*options);
std::shared_ptr<Cache> tc(NewLRUCache(options->max_open_files - 10,
options->table_cache_numshardbits));
WriteController wc(options->delayed_write_rate);
WriteBufferManager wb(options->db_write_buffer_size);
VersionSet versions(dbname, &db_options, file_options, tc.get(), &wb, &wc,
/*block_cache_tracer=*/nullptr);
Status status;
std::vector<ColumnFamilyDescriptor> dummy;
ColumnFamilyDescriptor dummy_descriptor(kDefaultColumnFamilyName,
ColumnFamilyOptions(*options));
dummy.push_back(dummy_descriptor);
status = versions.Recover(dummy);
if (!status.ok()) {
return status;
}
Version* current_version =
versions.GetColumnFamilySet()->GetDefault()->current();
auto* vstorage = current_version->storage_info();
int current_levels = vstorage->num_levels();
if (current_levels <= new_levels) {
return Status::OK();
}
// Make sure there are file only on one level from
// (new_levels-1) to (current_levels-1)
int first_nonempty_level = -1;
int first_nonempty_level_filenum = 0;
for (int i = new_levels - 1; i < current_levels; i++) {
int file_num = vstorage->NumLevelFiles(i);
if (file_num != 0) {
if (first_nonempty_level < 0) {
first_nonempty_level = i;
first_nonempty_level_filenum = file_num;
} else {
char msg[255];
snprintf(msg, sizeof(msg),
"Found at least two levels containing files: "
"[%d:%d],[%d:%d].\n",
first_nonempty_level, first_nonempty_level_filenum, i,
file_num);
return Status::InvalidArgument(msg);
}
}
}
// we need to allocate an array with the old number of levels size to
// avoid SIGSEGV in WriteCurrentStatetoManifest()
// however, all levels bigger or equal to new_levels will be empty
std::vector<FileMetaData*>* new_files_list =
new std::vector<FileMetaData*>[current_levels];
for (int i = 0; i < new_levels - 1; i++) {
new_files_list[i] = vstorage->LevelFiles(i);
}
if (first_nonempty_level > 0) {
new_files_list[new_levels - 1] = vstorage->LevelFiles(first_nonempty_level);
}
delete[] vstorage -> files_;
vstorage->files_ = new_files_list;
vstorage->num_levels_ = new_levels;
MutableCFOptions mutable_cf_options(*options);
VersionEdit ve;
InstrumentedMutex dummy_mutex;
InstrumentedMutexLock l(&dummy_mutex);
return versions.LogAndApply(
versions.GetColumnFamilySet()->GetDefault(),
mutable_cf_options, &ve, &dummy_mutex, nullptr, true);
}
// Get the checksum information including the checksum and checksum function
// name of all SST files in VersionSet. Store the information in
// FileChecksumList which contains a map from file number to its checksum info.
// If DB is not running, make sure call VersionSet::Recover() to load the file
// metadata from Manifest to VersionSet before calling this function.
Status VersionSet::GetLiveFilesChecksumInfo(FileChecksumList* checksum_list) {
// Clean the previously stored checksum information if any.
if (checksum_list == nullptr) {
return Status::InvalidArgument("checksum_list is nullptr");
}
checksum_list->reset();
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped() || !cfd->initialized()) {
continue;
}
for (int level = 0; level < cfd->NumberLevels(); level++) {
for (const auto& file :
cfd->current()->storage_info()->LevelFiles(level)) {
checksum_list->InsertOneFileChecksum(file->fd.GetNumber(),
file->file_checksum,
file->file_checksum_func_name);
}
}
}
return Status::OK();
}
Status VersionSet::DumpManifest(Options& options, std::string& dscname,
bool verbose, bool hex, bool json) {
// Open the specified manifest file.
std::unique_ptr<SequentialFileReader> file_reader;
Status s;
{
std::unique_ptr<FSSequentialFile> file;
s = options.file_system->NewSequentialFile(
dscname,
options.file_system->OptimizeForManifestRead(file_options_), &file,
nullptr);
if (!s.ok()) {
return s;
}
file_reader.reset(new SequentialFileReader(
std::move(file), dscname, db_options_->log_readahead_size));
}
bool have_prev_log_number = false;
bool have_next_file = false;
bool have_last_sequence = false;
uint64_t next_file = 0;
uint64_t last_sequence = 0;
uint64_t previous_log_number = 0;
int count = 0;
std::unordered_map<uint32_t, std::string> comparators;
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
builders;
// add default column family
VersionEdit default_cf_edit;
default_cf_edit.AddColumnFamily(kDefaultColumnFamilyName);
default_cf_edit.SetColumnFamily(0);
ColumnFamilyData* default_cfd =
CreateColumnFamily(ColumnFamilyOptions(options), &default_cf_edit);
builders.insert(
std::make_pair(0, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(default_cfd))));
{
VersionSet::LogReporter reporter;
reporter.status = &s;
log::Reader reader(nullptr, std::move(file_reader), &reporter,
true /* checksum */, 0 /* log_number */);
Slice record;
std::string scratch;
while (reader.ReadRecord(&record, &scratch) && s.ok()) {
VersionEdit edit;
s = edit.DecodeFrom(record);
if (!s.ok()) {
break;
}
// Write out each individual edit
if (verbose && !json) {
printf("%s\n", edit.DebugString(hex).c_str());
} else if (json) {
printf("%s\n", edit.DebugJSON(count, hex).c_str());
}
count++;
bool cf_in_builders =
builders.find(edit.column_family_) != builders.end();
if (edit.has_comparator_) {
comparators.insert({edit.column_family_, edit.comparator_});
}
ColumnFamilyData* cfd = nullptr;
if (edit.is_column_family_add_) {
if (cf_in_builders) {
s = Status::Corruption(
"Manifest adding the same column family twice");
break;
}
cfd = CreateColumnFamily(ColumnFamilyOptions(options), &edit);
cfd->set_initialized();
builders.insert(std::make_pair(
edit.column_family_, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(cfd))));
} else if (edit.is_column_family_drop_) {
if (!cf_in_builders) {
s = Status::Corruption(
"Manifest - dropping non-existing column family");
break;
}
auto builder_iter = builders.find(edit.column_family_);
builders.erase(builder_iter);
comparators.erase(edit.column_family_);
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
assert(cfd != nullptr);
cfd->UnrefAndTryDelete();
cfd = nullptr;
} else {
if (!cf_in_builders) {
s = Status::Corruption(
"Manifest record referencing unknown column family");
break;
}
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
// this should never happen since cf_in_builders is true
assert(cfd != nullptr);
// if it is not column family add or column family drop,
// then it's a file add/delete, which should be forwarded
// to builder
auto builder = builders.find(edit.column_family_);
assert(builder != builders.end());
s = builder->second->version_builder()->Apply(&edit);
if (!s.ok()) {
break;
}
}
if (cfd != nullptr && edit.has_log_number_) {
cfd->SetLogNumber(edit.log_number_);
}
if (edit.has_prev_log_number_) {
previous_log_number = edit.prev_log_number_;
have_prev_log_number = true;
}
if (edit.has_next_file_number_) {
next_file = edit.next_file_number_;
have_next_file = true;
}
if (edit.has_last_sequence_) {
last_sequence = edit.last_sequence_;
have_last_sequence = true;
}
if (edit.has_max_column_family_) {
column_family_set_->UpdateMaxColumnFamily(edit.max_column_family_);
}
if (edit.has_min_log_number_to_keep_) {
MarkMinLogNumberToKeep2PC(edit.min_log_number_to_keep_);
}
}
}
file_reader.reset();
if (s.ok()) {
if (!have_next_file) {
s = Status::Corruption("no meta-nextfile entry in descriptor");
printf("no meta-nextfile entry in descriptor");
} else if (!have_last_sequence) {
printf("no last-sequence-number entry in descriptor");
s = Status::Corruption("no last-sequence-number entry in descriptor");
}
if (!have_prev_log_number) {
previous_log_number = 0;
}
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
auto builders_iter = builders.find(cfd->GetID());
assert(builders_iter != builders.end());
auto builder = builders_iter->second->version_builder();
Version* v = new Version(cfd, this, file_options_,
*cfd->GetLatestMutableCFOptions(),
current_version_number_++);
builder->SaveTo(v->storage_info());
v->PrepareApply(*cfd->GetLatestMutableCFOptions(), false);
printf("--------------- Column family \"%s\" (ID %" PRIu32
") --------------\n",
cfd->GetName().c_str(), cfd->GetID());
printf("log number: %" PRIu64 "\n", cfd->GetLogNumber());
auto comparator = comparators.find(cfd->GetID());
if (comparator != comparators.end()) {
printf("comparator: %s\n", comparator->second.c_str());
} else {
printf("comparator: <NO COMPARATOR>\n");
}
printf("%s \n", v->DebugString(hex).c_str());
delete v;
}
next_file_number_.store(next_file + 1);
last_allocated_sequence_ = last_sequence;
last_published_sequence_ = last_sequence;
last_sequence_ = last_sequence;
prev_log_number_ = previous_log_number;
printf("next_file_number %" PRIu64 " last_sequence %" PRIu64
" prev_log_number %" PRIu64 " max_column_family %" PRIu32
" min_log_number_to_keep "
"%" PRIu64 "\n",
next_file_number_.load(), last_sequence, previous_log_number,
column_family_set_->GetMaxColumnFamily(),
min_log_number_to_keep_2pc());
}
return s;
}
#endif // ROCKSDB_LITE
void VersionSet::MarkFileNumberUsed(uint64_t number) {
// only called during recovery and repair which are single threaded, so this
// works because there can't be concurrent calls
if (next_file_number_.load(std::memory_order_relaxed) <= number) {
next_file_number_.store(number + 1, std::memory_order_relaxed);
}
}
// Called only either from ::LogAndApply which is protected by mutex or during
// recovery which is single-threaded.
void VersionSet::MarkMinLogNumberToKeep2PC(uint64_t number) {
if (min_log_number_to_keep_2pc_.load(std::memory_order_relaxed) < number) {
min_log_number_to_keep_2pc_.store(number, std::memory_order_relaxed);
}
}
Status VersionSet::WriteCurrentStateToManifest(
const std::unordered_map<uint32_t, MutableCFState>& curr_state,
log::Writer* log) {
// TODO: Break up into multiple records to reduce memory usage on recovery?
// WARNING: This method doesn't hold a mutex!!
// This is done without DB mutex lock held, but only within single-threaded
// LogAndApply. Column family manipulations can only happen within LogAndApply
// (the same single thread), so we're safe to iterate.
if (db_options_->write_dbid_to_manifest) {
VersionEdit edit_for_db_id;
assert(!db_id_.empty());
edit_for_db_id.SetDBId(db_id_);
std::string db_id_record;
if (!edit_for_db_id.EncodeTo(&db_id_record)) {
return Status::Corruption("Unable to Encode VersionEdit:" +
edit_for_db_id.DebugString(true));
}
Status add_record = log->AddRecord(db_id_record);
if (!add_record.ok()) {
return add_record;
}
}
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
assert(cfd->initialized());
{
// Store column family info
VersionEdit edit;
if (cfd->GetID() != 0) {
// default column family is always there,
// no need to explicitly write it
edit.AddColumnFamily(cfd->GetName());
edit.SetColumnFamily(cfd->GetID());
}
edit.SetComparatorName(
cfd->internal_comparator().user_comparator()->Name());
std::string record;
if (!edit.EncodeTo(&record)) {
return Status::Corruption(
"Unable to Encode VersionEdit:" + edit.DebugString(true));
}
Status s = log->AddRecord(record);
if (!s.ok()) {
return s;
}
}
{
// Save files
VersionEdit edit;
edit.SetColumnFamily(cfd->GetID());
for (int level = 0; level < cfd->NumberLevels(); level++) {
for (const auto& f :
cfd->current()->storage_info()->LevelFiles(level)) {
edit.AddFile(level, f->fd.GetNumber(), f->fd.GetPathId(),
f->fd.GetFileSize(), f->smallest, f->largest,
f->fd.smallest_seqno, f->fd.largest_seqno,
f->marked_for_compaction, f->oldest_blob_file_number,
f->oldest_ancester_time, f->file_creation_time,
f->file_checksum, f->file_checksum_func_name);
}
}
const auto iter = curr_state.find(cfd->GetID());
assert(iter != curr_state.end());
uint64_t log_number = iter->second.log_number;
edit.SetLogNumber(log_number);
std::string record;
if (!edit.EncodeTo(&record)) {
return Status::Corruption(
"Unable to Encode VersionEdit:" + edit.DebugString(true));
}
Status s = log->AddRecord(record);
if (!s.ok()) {
return s;
}
}
}
return Status::OK();
}
// TODO(aekmekji): in CompactionJob::GenSubcompactionBoundaries(), this
// function is called repeatedly with consecutive pairs of slices. For example
// if the slice list is [a, b, c, d] this function is called with arguments
// (a,b) then (b,c) then (c,d). Knowing this, an optimization is possible where
// we avoid doing binary search for the keys b and c twice and instead somehow
// maintain state of where they first appear in the files.
uint64_t VersionSet::ApproximateSize(const SizeApproximationOptions& options,
Version* v, const Slice& start,
const Slice& end, int start_level,
int end_level, TableReaderCaller caller) {
const auto& icmp = v->cfd_->internal_comparator();
// pre-condition
assert(icmp.Compare(start, end) <= 0);
uint64_t total_full_size = 0;
const auto* vstorage = v->storage_info();
const int num_non_empty_levels = vstorage->num_non_empty_levels();
end_level = (end_level == -1) ? num_non_empty_levels
: std::min(end_level, num_non_empty_levels);
assert(start_level <= end_level);
// Outline of the optimization that uses options.files_size_error_margin.
// When approximating the files total size that is used to store a keys range,
// we first sum up the sizes of the files that fully fall into the range.
// Then we sum up the sizes of all the files that may intersect with the range
// (this includes all files in L0 as well). Then, if total_intersecting_size
// is smaller than total_full_size * options.files_size_error_margin - we can
// infer that the intersecting files have a sufficiently negligible
// contribution to the total size, and we can approximate the storage required
// for the keys in range as just half of the intersecting_files_size.
// E.g., if the value of files_size_error_margin is 0.1, then the error of the
// approximation is limited to only ~10% of the total size of files that fully
// fall into the keys range. In such case, this helps to avoid a costly
// process of binary searching the intersecting files that is required only
// for a more precise calculation of the total size.
autovector<FdWithKeyRange*, 32> first_files;
autovector<FdWithKeyRange*, 16> last_files;
// scan all the levels
for (int level = start_level; level < end_level; ++level) {
const LevelFilesBrief& files_brief = vstorage->LevelFilesBrief(level);
if (files_brief.num_files == 0) {
// empty level, skip exploration
continue;
}
if (level == 0) {
// level 0 files are not in sorted order, we need to iterate through
// the list to compute the total bytes that require scanning,
// so handle the case explicitly (similarly to first_files case)
for (size_t i = 0; i < files_brief.num_files; i++) {
first_files.push_back(&files_brief.files[i]);
}
continue;
}
assert(level > 0);
assert(files_brief.num_files > 0);
// identify the file position for start key
const int idx_start =
FindFileInRange(icmp, files_brief, start, 0,
static_cast<uint32_t>(files_brief.num_files - 1));
assert(static_cast<size_t>(idx_start) < files_brief.num_files);
// identify the file position for end key
int idx_end = idx_start;
if (icmp.Compare(files_brief.files[idx_end].largest_key, end) < 0) {
idx_end =
FindFileInRange(icmp, files_brief, end, idx_start,
static_cast<uint32_t>(files_brief.num_files - 1));
}
assert(idx_end >= idx_start &&
static_cast<size_t>(idx_end) < files_brief.num_files);
// scan all files from the starting index to the ending index
// (inferred from the sorted order)
// first scan all the intermediate full files (excluding first and last)
for (int i = idx_start + 1; i < idx_end; ++i) {
uint64_t file_size = files_brief.files[i].fd.GetFileSize();
// The entire file falls into the range, so we can just take its size.
assert(file_size ==
ApproximateSize(v, files_brief.files[i], start, end, caller));
total_full_size += file_size;
}
// save the first and the last files (which may be the same file), so we
// can scan them later.
first_files.push_back(&files_brief.files[idx_start]);
if (idx_start != idx_end) {
// we need to estimate size for both files, only if they are different
last_files.push_back(&files_brief.files[idx_end]);
}
}
// The sum of all file sizes that intersect the [start, end] keys range.
uint64_t total_intersecting_size = 0;
for (const auto* file_ptr : first_files) {
total_intersecting_size += file_ptr->fd.GetFileSize();
}
for (const auto* file_ptr : last_files) {
total_intersecting_size += file_ptr->fd.GetFileSize();
}
// Now scan all the first & last files at each level, and estimate their size.
// If the total_intersecting_size is less than X% of the total_full_size - we
// want to approximate the result in order to avoid the costly binary search
// inside ApproximateSize. We use half of file size as an approximation below.
const double margin = options.files_size_error_margin;
if (margin > 0 && total_intersecting_size <
static_cast<uint64_t>(total_full_size * margin)) {
total_full_size += total_intersecting_size / 2;
} else {
// Estimate for all the first files, at each level
for (const auto file_ptr : first_files) {
total_full_size += ApproximateSize(v, *file_ptr, start, end, caller);
}
// Estimate for all the last files, at each level
for (const auto file_ptr : last_files) {
// We could use ApproximateSize here, but calling ApproximateOffsetOf
// directly is just more efficient.
total_full_size += ApproximateOffsetOf(v, *file_ptr, end, caller);
}
}
return total_full_size;
}
uint64_t VersionSet::ApproximateOffsetOf(Version* v, const FdWithKeyRange& f,
const Slice& key,
TableReaderCaller caller) {
// pre-condition
assert(v);
const auto& icmp = v->cfd_->internal_comparator();
uint64_t result = 0;
if (icmp.Compare(f.largest_key, key) <= 0) {
// Entire file is before "key", so just add the file size
result = f.fd.GetFileSize();
} else if (icmp.Compare(f.smallest_key, key) > 0) {
// Entire file is after "key", so ignore
result = 0;
} else {
// "key" falls in the range for this table. Add the
// approximate offset of "key" within the table.
TableCache* table_cache = v->cfd_->table_cache();
if (table_cache != nullptr) {
result = table_cache->ApproximateOffsetOf(
key, f.file_metadata->fd, caller, icmp,
v->GetMutableCFOptions().prefix_extractor.get());
}
}
return result;
}
uint64_t VersionSet::ApproximateSize(Version* v, const FdWithKeyRange& f,
const Slice& start, const Slice& end,
TableReaderCaller caller) {
// pre-condition
assert(v);
const auto& icmp = v->cfd_->internal_comparator();
assert(icmp.Compare(start, end) <= 0);
if (icmp.Compare(f.largest_key, start) <= 0 ||
icmp.Compare(f.smallest_key, end) > 0) {
// Entire file is before or after the start/end keys range
return 0;
}
if (icmp.Compare(f.smallest_key, start) >= 0) {
// Start of the range is before the file start - approximate by end offset
return ApproximateOffsetOf(v, f, end, caller);
}
if (icmp.Compare(f.largest_key, end) < 0) {
// End of the range is after the file end - approximate by subtracting
// start offset from the file size
uint64_t start_offset = ApproximateOffsetOf(v, f, start, caller);
assert(f.fd.GetFileSize() >= start_offset);
return f.fd.GetFileSize() - start_offset;
}
// The interval falls entirely in the range for this file.
TableCache* table_cache = v->cfd_->table_cache();
if (table_cache == nullptr) {
return 0;
}
return table_cache->ApproximateSize(
start, end, f.file_metadata->fd, caller, icmp,
v->GetMutableCFOptions().prefix_extractor.get());
}
void VersionSet::AddLiveFiles(std::vector<FileDescriptor>* live_list) {
// pre-calculate space requirement
int64_t total_files = 0;
for (auto cfd : *column_family_set_) {
if (!cfd->initialized()) {
continue;
}
Version* dummy_versions = cfd->dummy_versions();
for (Version* v = dummy_versions->next_; v != dummy_versions;
v = v->next_) {
const auto* vstorage = v->storage_info();
for (int level = 0; level < vstorage->num_levels(); level++) {
total_files += vstorage->LevelFiles(level).size();
}
}
}
// just one time extension to the right size
live_list->reserve(live_list->size() + static_cast<size_t>(total_files));
for (auto cfd : *column_family_set_) {
if (!cfd->initialized()) {
continue;
}
auto* current = cfd->current();
bool found_current = false;
Version* dummy_versions = cfd->dummy_versions();
for (Version* v = dummy_versions->next_; v != dummy_versions;
v = v->next_) {
v->AddLiveFiles(live_list);
if (v == current) {
found_current = true;
}
}
if (!found_current && current != nullptr) {
// Should never happen unless it is a bug.
assert(false);
current->AddLiveFiles(live_list);
}
}
}
InternalIterator* VersionSet::MakeInputIterator(
const Compaction* c, RangeDelAggregator* range_del_agg,
const FileOptions& file_options_compactions) {
auto cfd = c->column_family_data();
ReadOptions read_options;
read_options.verify_checksums = true;
read_options.fill_cache = false;
// Compaction iterators shouldn't be confined to a single prefix.
// Compactions use Seek() for
// (a) concurrent compactions,
// (b) CompactionFilter::Decision::kRemoveAndSkipUntil.
read_options.total_order_seek = true;
// Level-0 files have to be merged together. For other levels,
// we will make a concatenating iterator per level.
// TODO(opt): use concatenating iterator for level-0 if there is no overlap
const size_t space = (c->level() == 0 ? c->input_levels(0)->num_files +
c->num_input_levels() - 1
: c->num_input_levels());
InternalIterator** list = new InternalIterator* [space];
size_t num = 0;
for (size_t which = 0; which < c->num_input_levels(); which++) {
if (c->input_levels(which)->num_files != 0) {
if (c->level(which) == 0) {
const LevelFilesBrief* flevel = c->input_levels(which);
for (size_t i = 0; i < flevel->num_files; i++) {
list[num++] = cfd->table_cache()->NewIterator(
read_options, file_options_compactions,
cfd->internal_comparator(),
*flevel->files[i].file_metadata, range_del_agg,
c->mutable_cf_options()->prefix_extractor.get(),
/*table_reader_ptr=*/nullptr,
/*file_read_hist=*/nullptr, TableReaderCaller::kCompaction,
/*arena=*/nullptr,
/*skip_filters=*/false, /*level=*/static_cast<int>(which),
/*smallest_compaction_key=*/nullptr,
/*largest_compaction_key=*/nullptr);
}
} else {
// Create concatenating iterator for the files from this level
list[num++] = new LevelIterator(
cfd->table_cache(), read_options, file_options_compactions,
cfd->internal_comparator(), c->input_levels(which),
c->mutable_cf_options()->prefix_extractor.get(),
/*should_sample=*/false,
/*no per level latency histogram=*/nullptr,
TableReaderCaller::kCompaction, /*skip_filters=*/false,
/*level=*/static_cast<int>(which), range_del_agg,
c->boundaries(which));
}
}
}
assert(num <= space);
InternalIterator* result =
NewMergingIterator(&c->column_family_data()->internal_comparator(), list,
static_cast<int>(num));
delete[] list;
return result;
}
// verify that the files listed in this compaction are present
// in the current version
bool VersionSet::VerifyCompactionFileConsistency(Compaction* c) {
#ifndef NDEBUG
Version* version = c->column_family_data()->current();
const VersionStorageInfo* vstorage = version->storage_info();
if (c->input_version() != version) {
ROCKS_LOG_INFO(
db_options_->info_log,
"[%s] compaction output being applied to a different base version from"
" input version",
c->column_family_data()->GetName().c_str());
if (vstorage->compaction_style_ == kCompactionStyleLevel &&
c->start_level() == 0 && c->num_input_levels() > 2U) {
// We are doing a L0->base_level compaction. The assumption is if
// base level is not L1, levels from L1 to base_level - 1 is empty.
// This is ensured by having one compaction from L0 going on at the
// same time in level-based compaction. So that during the time, no
// compaction/flush can put files to those levels.
for (int l = c->start_level() + 1; l < c->output_level(); l++) {
if (vstorage->NumLevelFiles(l) != 0) {
return false;
}
}
}
}
for (size_t input = 0; input < c->num_input_levels(); ++input) {
int level = c->level(input);
for (size_t i = 0; i < c->num_input_files(input); ++i) {
uint64_t number = c->input(input, i)->fd.GetNumber();
bool found = false;
for (size_t j = 0; j < vstorage->files_[level].size(); j++) {
FileMetaData* f = vstorage->files_[level][j];
if (f->fd.GetNumber() == number) {
found = true;
break;
}
}
if (!found) {
return false; // input files non existent in current version
}
}
}
#else
(void)c;
#endif
return true; // everything good
}
Status VersionSet::GetMetadataForFile(uint64_t number, int* filelevel,
FileMetaData** meta,
ColumnFamilyData** cfd) {
for (auto cfd_iter : *column_family_set_) {
if (!cfd_iter->initialized()) {
continue;
}
Version* version = cfd_iter->current();
const auto* vstorage = version->storage_info();
for (int level = 0; level < vstorage->num_levels(); level++) {
for (const auto& file : vstorage->LevelFiles(level)) {
if (file->fd.GetNumber() == number) {
*meta = file;
*filelevel = level;
*cfd = cfd_iter;
return Status::OK();
}
}
}
}
return Status::NotFound("File not present in any level");
}
void VersionSet::GetLiveFilesMetaData(std::vector<LiveFileMetaData>* metadata) {
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped() || !cfd->initialized()) {
continue;
}
for (int level = 0; level < cfd->NumberLevels(); level++) {
for (const auto& file :
cfd->current()->storage_info()->LevelFiles(level)) {
LiveFileMetaData filemetadata;
filemetadata.column_family_name = cfd->GetName();
uint32_t path_id = file->fd.GetPathId();
if (path_id < cfd->ioptions()->cf_paths.size()) {
filemetadata.db_path = cfd->ioptions()->cf_paths[path_id].path;
} else {
assert(!cfd->ioptions()->cf_paths.empty());
filemetadata.db_path = cfd->ioptions()->cf_paths.back().path;
}
const uint64_t file_number = file->fd.GetNumber();
filemetadata.name = MakeTableFileName("", file_number);
filemetadata.file_number = file_number;
filemetadata.level = level;
filemetadata.size = static_cast<size_t>(file->fd.GetFileSize());
filemetadata.smallestkey = file->smallest.user_key().ToString();
filemetadata.largestkey = file->largest.user_key().ToString();
filemetadata.smallest_seqno = file->fd.smallest_seqno;
filemetadata.largest_seqno = file->fd.largest_seqno;
filemetadata.num_reads_sampled = file->stats.num_reads_sampled.load(
std::memory_order_relaxed);
filemetadata.being_compacted = file->being_compacted;
filemetadata.num_entries = file->num_entries;
filemetadata.num_deletions = file->num_deletions;
filemetadata.oldest_blob_file_number = file->oldest_blob_file_number;
filemetadata.file_checksum = file->file_checksum;
filemetadata.file_checksum_func_name = file->file_checksum_func_name;
metadata->push_back(filemetadata);
}
}
}
}
void VersionSet::GetObsoleteFiles(std::vector<ObsoleteFileInfo>* files,
std::vector<std::string>* manifest_filenames,
uint64_t min_pending_output) {
assert(manifest_filenames->empty());
obsolete_manifests_.swap(*manifest_filenames);
std::vector<ObsoleteFileInfo> pending_files;
for (auto& f : obsolete_files_) {
if (f.metadata->fd.GetNumber() < min_pending_output) {
files->push_back(std::move(f));
} else {
pending_files.push_back(std::move(f));
}
}
obsolete_files_.swap(pending_files);
}
ColumnFamilyData* VersionSet::CreateColumnFamily(
const ColumnFamilyOptions& cf_options, VersionEdit* edit) {
assert(edit->is_column_family_add_);
MutableCFOptions dummy_cf_options;
Version* dummy_versions =
new Version(nullptr, this, file_options_, dummy_cf_options);
// Ref() dummy version once so that later we can call Unref() to delete it
// by avoiding calling "delete" explicitly (~Version is private)
dummy_versions->Ref();
auto new_cfd = column_family_set_->CreateColumnFamily(
edit->column_family_name_, edit->column_family_, dummy_versions,
cf_options);
Version* v = new Version(new_cfd, this, file_options_,
*new_cfd->GetLatestMutableCFOptions(),
current_version_number_++);
// Fill level target base information.
v->storage_info()->CalculateBaseBytes(*new_cfd->ioptions(),
*new_cfd->GetLatestMutableCFOptions());
AppendVersion(new_cfd, v);
// GetLatestMutableCFOptions() is safe here without mutex since the
// cfd is not available to client
new_cfd->CreateNewMemtable(*new_cfd->GetLatestMutableCFOptions(),
LastSequence());
new_cfd->SetLogNumber(edit->log_number_);
return new_cfd;
}
uint64_t VersionSet::GetNumLiveVersions(Version* dummy_versions) {
uint64_t count = 0;
for (Version* v = dummy_versions->next_; v != dummy_versions; v = v->next_) {
count++;
}
return count;
}
uint64_t VersionSet::GetTotalSstFilesSize(Version* dummy_versions) {
std::unordered_set<uint64_t> unique_files;
uint64_t total_files_size = 0;
for (Version* v = dummy_versions->next_; v != dummy_versions; v = v->next_) {
VersionStorageInfo* storage_info = v->storage_info();
for (int level = 0; level < storage_info->num_levels_; level++) {
for (const auto& file_meta : storage_info->LevelFiles(level)) {
if (unique_files.find(file_meta->fd.packed_number_and_path_id) ==
unique_files.end()) {
unique_files.insert(file_meta->fd.packed_number_and_path_id);
total_files_size += file_meta->fd.GetFileSize();
}
}
}
}
return total_files_size;
}
ReactiveVersionSet::ReactiveVersionSet(const std::string& dbname,
const ImmutableDBOptions* _db_options,
const FileOptions& _file_options,
Cache* table_cache,
WriteBufferManager* write_buffer_manager,
WriteController* write_controller)
: VersionSet(dbname, _db_options, _file_options, table_cache,
write_buffer_manager, write_controller,
/*block_cache_tracer=*/nullptr),
number_of_edits_to_skip_(0) {}
ReactiveVersionSet::~ReactiveVersionSet() {}
Status ReactiveVersionSet::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader,
std::unique_ptr<log::Reader::Reporter>* manifest_reporter,
std::unique_ptr<Status>* manifest_reader_status) {
assert(manifest_reader != nullptr);
assert(manifest_reporter != nullptr);
assert(manifest_reader_status != nullptr);
std::unordered_map<std::string, ColumnFamilyOptions> cf_name_to_options;
for (const auto& cf : column_families) {
cf_name_to_options.insert({cf.name, cf.options});
}
// add default column family
auto default_cf_iter = cf_name_to_options.find(kDefaultColumnFamilyName);
if (default_cf_iter == cf_name_to_options.end()) {
return Status::InvalidArgument("Default column family not specified");
}
VersionEdit default_cf_edit;
default_cf_edit.AddColumnFamily(kDefaultColumnFamilyName);
default_cf_edit.SetColumnFamily(0);
ColumnFamilyData* default_cfd =
CreateColumnFamily(default_cf_iter->second, &default_cf_edit);
// In recovery, nobody else can access it, so it's fine to set it to be
// initialized earlier.
default_cfd->set_initialized();
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
builders;
std::unordered_map<int, std::string> column_families_not_found;
builders.insert(
std::make_pair(0, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(default_cfd))));
manifest_reader_status->reset(new Status());
manifest_reporter->reset(new LogReporter());
static_cast<LogReporter*>(manifest_reporter->get())->status =
manifest_reader_status->get();
Status s = MaybeSwitchManifest(manifest_reporter->get(), manifest_reader);
log::Reader* reader = manifest_reader->get();
int retry = 0;
VersionEdit version_edit;
while (s.ok() && retry < 1) {
assert(reader != nullptr);
Slice record;
std::string scratch;
s = ReadAndRecover(reader, &read_buffer_, cf_name_to_options,
column_families_not_found, builders, &version_edit);
if (s.ok()) {
bool enough = version_edit.has_next_file_number_ &&
version_edit.has_log_number_ &&
version_edit.has_last_sequence_;
if (enough) {
for (const auto& cf : column_families) {
auto cfd = column_family_set_->GetColumnFamily(cf.name);
if (cfd == nullptr) {
enough = false;
break;
}
}
}
if (enough) {
for (const auto& cf : column_families) {
auto cfd = column_family_set_->GetColumnFamily(cf.name);
assert(cfd != nullptr);
if (!cfd->IsDropped()) {
auto builder_iter = builders.find(cfd->GetID());
assert(builder_iter != builders.end());
auto builder = builder_iter->second->version_builder();
assert(builder != nullptr);
s = builder->LoadTableHandlers(
cfd->internal_stats(), db_options_->max_file_opening_threads,
false /* prefetch_index_and_filter_in_cache */,
true /* is_initial_load */,
cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
if (!s.ok()) {
enough = false;
if (s.IsPathNotFound()) {
s = Status::OK();
}
break;
}
}
}
}
if (enough) {
break;
}
}
++retry;
}
if (s.ok()) {
if (!version_edit.has_prev_log_number_) {
version_edit.prev_log_number_ = 0;
}
column_family_set_->UpdateMaxColumnFamily(version_edit.max_column_family_);
MarkMinLogNumberToKeep2PC(version_edit.min_log_number_to_keep_);
MarkFileNumberUsed(version_edit.prev_log_number_);
MarkFileNumberUsed(version_edit.log_number_);
for (auto cfd : *column_family_set_) {
assert(builders.count(cfd->GetID()) > 0);
auto builder = builders[cfd->GetID()]->version_builder();
if (!builder->CheckConsistencyForNumLevels()) {
s = Status::InvalidArgument(
"db has more levels than options.num_levels");
break;
}
}
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
assert(cfd->initialized());
auto builders_iter = builders.find(cfd->GetID());
assert(builders_iter != builders.end());
auto* builder = builders_iter->second->version_builder();
Version* v = new Version(cfd, this, file_options_,
*cfd->GetLatestMutableCFOptions(),
current_version_number_++);
builder->SaveTo(v->storage_info());
// Install recovered version
v->PrepareApply(*cfd->GetLatestMutableCFOptions(),
!(db_options_->skip_stats_update_on_db_open));
AppendVersion(cfd, v);
}
next_file_number_.store(version_edit.next_file_number_ + 1);
last_allocated_sequence_ = version_edit.last_sequence_;
last_published_sequence_ = version_edit.last_sequence_;
last_sequence_ = version_edit.last_sequence_;
prev_log_number_ = version_edit.prev_log_number_;
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
ROCKS_LOG_INFO(db_options_->info_log,
"Column family [%s] (ID %u), log number is %" PRIu64 "\n",
cfd->GetName().c_str(), cfd->GetID(), cfd->GetLogNumber());
}
}
return s;
}
Status ReactiveVersionSet::ReadAndApply(
InstrumentedMutex* mu,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader,
std::unordered_set<ColumnFamilyData*>* cfds_changed) {
assert(manifest_reader != nullptr);
assert(cfds_changed != nullptr);
mu->AssertHeld();
Status s;
uint64_t applied_edits = 0;
while (s.ok()) {
Slice record;
std::string scratch;
log::Reader* reader = manifest_reader->get();
std::string old_manifest_path = reader->file()->file_name();
while (reader->ReadRecord(&record, &scratch)) {
VersionEdit edit;
s = edit.DecodeFrom(record);
if (!s.ok()) {
break;
}
// Skip the first VersionEdits of each MANIFEST generated by
// VersionSet::WriteCurrentStatetoManifest.
if (number_of_edits_to_skip_ > 0) {
ColumnFamilyData* cfd =
column_family_set_->GetColumnFamily(edit.column_family_);
if (cfd != nullptr && !cfd->IsDropped()) {
--number_of_edits_to_skip_;
}
continue;
}
s = read_buffer_.AddEdit(&edit);
if (!s.ok()) {
break;
}
VersionEdit temp_edit;
if (edit.is_in_atomic_group_) {
if (read_buffer_.IsFull()) {
// Apply edits in an atomic group when we have read all edits in the
// group.
for (auto& e : read_buffer_.replay_buffer()) {
s = ApplyOneVersionEditToBuilder(e, cfds_changed, &temp_edit);
if (!s.ok()) {
break;
}
applied_edits++;
}
if (!s.ok()) {
break;
}
read_buffer_.Clear();
}
} else {
// Apply a normal edit immediately.
s = ApplyOneVersionEditToBuilder(edit, cfds_changed, &temp_edit);
if (s.ok()) {
applied_edits++;
}
}
}
if (!s.ok()) {
// Clear the buffer if we fail to decode/apply an edit.
read_buffer_.Clear();
}
// It's possible that:
// 1) s.IsCorruption(), indicating the current MANIFEST is corrupted.
// 2) we have finished reading the current MANIFEST.
// 3) we have encountered an IOError reading the current MANIFEST.
// We need to look for the next MANIFEST and start from there. If we cannot
// find the next MANIFEST, we should exit the loop.
s = MaybeSwitchManifest(reader->GetReporter(), manifest_reader);
reader = manifest_reader->get();
if (s.ok()) {
if (reader->file()->file_name() == old_manifest_path) {
// Still processing the same MANIFEST, thus no need to continue this
// loop since no record is available if we have reached here.
break;
} else {
// We have switched to a new MANIFEST whose first records have been
// generated by VersionSet::WriteCurrentStatetoManifest. Since the
// secondary instance has already finished recovering upon start, there
// is no need for the secondary to process these records. Actually, if
// the secondary were to replay these records, the secondary may end up
// adding the same SST files AGAIN to each column family, causing
// consistency checks done by VersionBuilder to fail. Therefore, we
// record the number of records to skip at the beginning of the new
// MANIFEST and ignore them.
number_of_edits_to_skip_ = 0;
for (auto* cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
// Increase number_of_edits_to_skip by 2 because
// WriteCurrentStatetoManifest() writes 2 version edits for each
// column family at the beginning of the newly-generated MANIFEST.
// TODO(yanqin) remove hard-coded value.
if (db_options_->write_dbid_to_manifest) {
number_of_edits_to_skip_ += 3;
} else {
number_of_edits_to_skip_ += 2;
}
}
}
}
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
auto builder_iter = active_version_builders_.find(cfd->GetID());
if (builder_iter == active_version_builders_.end()) {
continue;
}
auto builder = builder_iter->second->version_builder();
if (!builder->CheckConsistencyForNumLevels()) {
s = Status::InvalidArgument(
"db has more levels than options.num_levels");
break;
}
}
}
TEST_SYNC_POINT_CALLBACK("ReactiveVersionSet::ReadAndApply:AppliedEdits",
&applied_edits);
return s;
}
Status ReactiveVersionSet::ApplyOneVersionEditToBuilder(
VersionEdit& edit, std::unordered_set<ColumnFamilyData*>* cfds_changed,
VersionEdit* version_edit) {
ColumnFamilyData* cfd =
column_family_set_->GetColumnFamily(edit.column_family_);
// If we cannot find this column family in our column family set, then it
// may be a new column family created by the primary after the secondary
// starts. It is also possible that the secondary instance opens only a subset
// of column families. Ignore it for now.
if (nullptr == cfd) {
return Status::OK();
}
if (active_version_builders_.find(edit.column_family_) ==
active_version_builders_.end() &&
!cfd->IsDropped()) {
std::unique_ptr<BaseReferencedVersionBuilder> builder_guard(
new BaseReferencedVersionBuilder(cfd));
active_version_builders_.insert(
std::make_pair(edit.column_family_, std::move(builder_guard)));
}
auto builder_iter = active_version_builders_.find(edit.column_family_);
assert(builder_iter != active_version_builders_.end());
auto builder = builder_iter->second->version_builder();
assert(builder != nullptr);
if (edit.is_column_family_add_) {
// TODO (yanqin) for now the secondary ignores column families created
// after Open. This also simplifies handling of switching to a new MANIFEST
// and processing the snapshot of the system at the beginning of the
// MANIFEST.
} else if (edit.is_column_family_drop_) {
// Drop the column family by setting it to be 'dropped' without destroying
// the column family handle.
// TODO (haoyu) figure out how to handle column faimly drop for
// secondary instance. (Is it possible that the ref count for cfd is 0 but
// the ref count for its versions is higher than 0?)
cfd->SetDropped();
if (cfd->UnrefAndTryDelete()) {
cfd = nullptr;
}
active_version_builders_.erase(builder_iter);
} else {
Status s = builder->Apply(&edit);
if (!s.ok()) {
return s;
}
}
Status s = ExtractInfoFromVersionEdit(cfd, edit, version_edit);
if (!s.ok()) {
return s;
}
if (cfd != nullptr && !cfd->IsDropped()) {
s = builder->LoadTableHandlers(
cfd->internal_stats(), db_options_->max_file_opening_threads,
false /* prefetch_index_and_filter_in_cache */,
false /* is_initial_load */,
cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
TEST_SYNC_POINT_CALLBACK(
"ReactiveVersionSet::ApplyOneVersionEditToBuilder:"
"AfterLoadTableHandlers",
&s);
if (s.ok()) {
auto version = new Version(cfd, this, file_options_,
*cfd->GetLatestMutableCFOptions(),
current_version_number_++);
builder->SaveTo(version->storage_info());
version->PrepareApply(*cfd->GetLatestMutableCFOptions(), true);
AppendVersion(cfd, version);
active_version_builders_.erase(builder_iter);
if (cfds_changed->count(cfd) == 0) {
cfds_changed->insert(cfd);
}
} else if (s.IsPathNotFound()) {
s = Status::OK();
}
// Some other error has occurred during LoadTableHandlers.
}
if (version_edit->HasNextFile()) {
next_file_number_.store(version_edit->next_file_number_ + 1);
}
if (version_edit->has_last_sequence_) {
last_allocated_sequence_ = version_edit->last_sequence_;
last_published_sequence_ = version_edit->last_sequence_;
last_sequence_ = version_edit->last_sequence_;
}
if (version_edit->has_prev_log_number_) {
prev_log_number_ = version_edit->prev_log_number_;
MarkFileNumberUsed(version_edit->prev_log_number_);
}
if (version_edit->has_log_number_) {
MarkFileNumberUsed(version_edit->log_number_);
}
column_family_set_->UpdateMaxColumnFamily(version_edit->max_column_family_);
MarkMinLogNumberToKeep2PC(version_edit->min_log_number_to_keep_);
return s;
}
Status ReactiveVersionSet::MaybeSwitchManifest(
log::Reader::Reporter* reporter,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader) {
assert(manifest_reader != nullptr);
Status s;
do {
std::string manifest_path;
s = GetCurrentManifestPath(dbname_, fs_, &manifest_path,
&manifest_file_number_);
std::unique_ptr<FSSequentialFile> manifest_file;
if (s.ok()) {
if (nullptr == manifest_reader->get() ||
manifest_reader->get()->file()->file_name() != manifest_path) {
TEST_SYNC_POINT(
"ReactiveVersionSet::MaybeSwitchManifest:"
"AfterGetCurrentManifestPath:0");
TEST_SYNC_POINT(
"ReactiveVersionSet::MaybeSwitchManifest:"
"AfterGetCurrentManifestPath:1");
s = fs_->NewSequentialFile(manifest_path,
env_->OptimizeForManifestRead(file_options_),
&manifest_file, nullptr);
} else {
// No need to switch manifest.
break;
}
}
std::unique_ptr<SequentialFileReader> manifest_file_reader;
if (s.ok()) {
manifest_file_reader.reset(
new SequentialFileReader(std::move(manifest_file), manifest_path,
db_options_->log_readahead_size));
manifest_reader->reset(new log::FragmentBufferedReader(
nullptr, std::move(manifest_file_reader), reporter,
true /* checksum */, 0 /* log_number */));
ROCKS_LOG_INFO(db_options_->info_log, "Switched to new manifest: %s\n",
manifest_path.c_str());
// TODO (yanqin) every time we switch to a new MANIFEST, we clear the
// active_version_builders_ map because we choose to construct the
// versions from scratch, thanks to the first part of each MANIFEST
// written by VersionSet::WriteCurrentStatetoManifest. This is not
// necessary, but we choose this at present for the sake of simplicity.
active_version_builders_.clear();
}
} while (s.IsPathNotFound());
return s;
}
} // namespace ROCKSDB_NAMESPACE