rocksdb/db/db_impl.cc
Igor Canadi 635905481d WalManager
Summary: Decoupling code that deals with archived log files outside of DBImpl. That will make this code easier to reason about and test. It will also make the code easier to improve, because an improver doesn't have to understand DBImpl code in entirety.

Test Plan: added test

Reviewers: ljin, yhchiang, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D27873
2014-10-29 17:43:37 -07:00

4450 lines
157 KiB
C++

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same 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/db_impl.h"
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
#include <algorithm>
#include <climits>
#include <cstdio>
#include <set>
#include <stdexcept>
#include <stdint.h>
#include <string>
#include <unordered_set>
#include <unordered_map>
#include <utility>
#include <vector>
#include "db/builder.h"
#include "db/flush_job.h"
#include "db/db_iter.h"
#include "db/dbformat.h"
#include "db/filename.h"
#include "db/log_reader.h"
#include "db/log_writer.h"
#include "db/memtable.h"
#include "db/memtable_list.h"
#include "db/merge_context.h"
#include "db/merge_helper.h"
#include "db/table_cache.h"
#include "db/table_properties_collector.h"
#include "db/forward_iterator.h"
#include "db/transaction_log_impl.h"
#include "db/version_set.h"
#include "db/write_batch_internal.h"
#include "port/port.h"
#include "rocksdb/cache.h"
#include "port/likely.h"
#include "rocksdb/compaction_filter.h"
#include "rocksdb/db.h"
#include "rocksdb/env.h"
#include "rocksdb/merge_operator.h"
#include "rocksdb/version.h"
#include "rocksdb/statistics.h"
#include "rocksdb/status.h"
#include "rocksdb/table.h"
#include "table/block.h"
#include "table/block_based_table_factory.h"
#include "table/merger.h"
#include "table/table_builder.h"
#include "table/two_level_iterator.h"
#include "util/auto_roll_logger.h"
#include "util/autovector.h"
#include "util/build_version.h"
#include "util/coding.h"
#include "util/hash_skiplist_rep.h"
#include "util/hash_linklist_rep.h"
#include "util/logging.h"
#include "util/log_buffer.h"
#include "util/mutexlock.h"
#include "util/perf_context_imp.h"
#include "util/iostats_context_imp.h"
#include "util/stop_watch.h"
#include "util/sync_point.h"
namespace rocksdb {
const std::string kDefaultColumnFamilyName("default");
void DumpRocksDBBuildVersion(Logger * log);
struct DBImpl::WriteContext {
autovector<SuperVersion*> superversions_to_free_;
autovector<log::Writer*> logs_to_free_;
~WriteContext() {
for (auto& sv : superversions_to_free_) {
delete sv;
}
for (auto& log : logs_to_free_) {
delete log;
}
}
};
struct DBImpl::CompactionState {
Compaction* const compaction;
// If there were two snapshots with seq numbers s1 and
// s2 and s1 < s2, and if we find two instances of a key k1 then lies
// entirely within s1 and s2, then the earlier version of k1 can be safely
// deleted because that version is not visible in any snapshot.
std::vector<SequenceNumber> existing_snapshots;
// Files produced by compaction
struct Output {
uint64_t number;
uint32_t path_id;
uint64_t file_size;
InternalKey smallest, largest;
SequenceNumber smallest_seqno, largest_seqno;
};
std::vector<Output> outputs;
std::list<uint64_t> allocated_file_numbers;
// State kept for output being generated
unique_ptr<WritableFile> outfile;
unique_ptr<TableBuilder> builder;
uint64_t total_bytes;
Output* current_output() { return &outputs[outputs.size()-1]; }
explicit CompactionState(Compaction* c)
: compaction(c),
total_bytes(0) {
}
// Create a client visible context of this compaction
CompactionFilter::Context GetFilterContextV1() {
CompactionFilter::Context context;
context.is_full_compaction = compaction->IsFullCompaction();
context.is_manual_compaction = compaction->IsManualCompaction();
return context;
}
// Create a client visible context of this compaction
CompactionFilterContext GetFilterContext() {
CompactionFilterContext context;
context.is_full_compaction = compaction->IsFullCompaction();
context.is_manual_compaction = compaction->IsManualCompaction();
return context;
}
std::vector<std::string> key_str_buf_;
std::vector<std::string> existing_value_str_buf_;
// new_value_buf_ will only be appended if a value changes
std::vector<std::string> new_value_buf_;
// if values_changed_buf_[i] is true
// new_value_buf_ will add a new entry with the changed value
std::vector<bool> value_changed_buf_;
// to_delete_buf_[i] is true iff key_buf_[i] is deleted
std::vector<bool> to_delete_buf_;
std::vector<std::string> other_key_str_buf_;
std::vector<std::string> other_value_str_buf_;
std::vector<Slice> combined_key_buf_;
std::vector<Slice> combined_value_buf_;
std::string cur_prefix_;
// Buffers the kv-pair that will be run through compaction filter V2
// in the future.
void BufferKeyValueSlices(const Slice& key, const Slice& value) {
key_str_buf_.emplace_back(key.ToString());
existing_value_str_buf_.emplace_back(value.ToString());
}
// Buffers the kv-pair that will not be run through compaction filter V2
// in the future.
void BufferOtherKeyValueSlices(const Slice& key, const Slice& value) {
other_key_str_buf_.emplace_back(key.ToString());
other_value_str_buf_.emplace_back(value.ToString());
}
// Add a kv-pair to the combined buffer
void AddToCombinedKeyValueSlices(const Slice& key, const Slice& value) {
// The real strings are stored in the batch buffers
combined_key_buf_.emplace_back(key);
combined_value_buf_.emplace_back(value);
}
// Merging the two buffers
void MergeKeyValueSliceBuffer(const InternalKeyComparator* comparator) {
size_t i = 0;
size_t j = 0;
size_t total_size = key_str_buf_.size() + other_key_str_buf_.size();
combined_key_buf_.reserve(total_size);
combined_value_buf_.reserve(total_size);
while (i + j < total_size) {
int comp_res = 0;
if (i < key_str_buf_.size() && j < other_key_str_buf_.size()) {
comp_res = comparator->Compare(key_str_buf_[i], other_key_str_buf_[j]);
} else if (i >= key_str_buf_.size() && j < other_key_str_buf_.size()) {
comp_res = 1;
} else if (j >= other_key_str_buf_.size() && i < key_str_buf_.size()) {
comp_res = -1;
}
if (comp_res > 0) {
AddToCombinedKeyValueSlices(other_key_str_buf_[j], other_value_str_buf_[j]);
j++;
} else if (comp_res < 0) {
AddToCombinedKeyValueSlices(key_str_buf_[i], existing_value_str_buf_[i]);
i++;
}
}
}
void CleanupBatchBuffer() {
to_delete_buf_.clear();
key_str_buf_.clear();
existing_value_str_buf_.clear();
new_value_buf_.clear();
value_changed_buf_.clear();
to_delete_buf_.shrink_to_fit();
key_str_buf_.shrink_to_fit();
existing_value_str_buf_.shrink_to_fit();
new_value_buf_.shrink_to_fit();
value_changed_buf_.shrink_to_fit();
other_key_str_buf_.clear();
other_value_str_buf_.clear();
other_key_str_buf_.shrink_to_fit();
other_value_str_buf_.shrink_to_fit();
}
void CleanupMergedBuffer() {
combined_key_buf_.clear();
combined_value_buf_.clear();
combined_key_buf_.shrink_to_fit();
combined_value_buf_.shrink_to_fit();
}
};
Options SanitizeOptions(const std::string& dbname,
const InternalKeyComparator* icmp,
const Options& src) {
auto db_options = SanitizeOptions(dbname, DBOptions(src));
auto cf_options = SanitizeOptions(icmp, ColumnFamilyOptions(src));
return Options(db_options, cf_options);
}
DBOptions SanitizeOptions(const std::string& dbname, const DBOptions& src) {
DBOptions result = src;
// result.max_open_files means an "infinite" open files.
if (result.max_open_files != -1) {
ClipToRange(&result.max_open_files, 20, 1000000);
}
if (result.info_log == nullptr) {
Status s = CreateLoggerFromOptions(dbname, result.db_log_dir, src.env,
result, &result.info_log);
if (!s.ok()) {
// No place suitable for logging
result.info_log = nullptr;
}
}
if (!result.rate_limiter) {
if (result.bytes_per_sync == 0) {
result.bytes_per_sync = 1024 * 1024;
}
}
if (result.wal_dir.empty()) {
// Use dbname as default
result.wal_dir = dbname;
}
if (result.wal_dir.back() == '/') {
result.wal_dir = result.wal_dir.substr(0, result.wal_dir.size() - 1);
}
if (result.db_paths.size() == 0) {
result.db_paths.emplace_back(dbname, std::numeric_limits<uint64_t>::max());
}
return result;
}
namespace {
Status SanitizeOptionsByTable(
const DBOptions& db_opts,
const std::vector<ColumnFamilyDescriptor>& column_families) {
Status s;
for (auto cf : column_families) {
s = cf.options.table_factory->SanitizeOptions(db_opts, cf.options);
if (!s.ok()) {
return s;
}
}
return Status::OK();
}
CompressionType GetCompressionFlush(const ImmutableCFOptions& ioptions) {
// Compressing memtable flushes might not help unless the sequential load
// optimization is used for leveled compaction. Otherwise the CPU and
// latency overhead is not offset by saving much space.
bool can_compress;
if (ioptions.compaction_style == kCompactionStyleUniversal) {
can_compress =
(ioptions.compaction_options_universal.compression_size_percent < 0);
} else {
// For leveled compress when min_level_to_compress == 0.
can_compress = ioptions.compression_per_level.empty() ||
ioptions.compression_per_level[0] != kNoCompression;
}
if (can_compress) {
return ioptions.compression;
} else {
return kNoCompression;
}
}
} // namespace
DBImpl::DBImpl(const DBOptions& options, const std::string& dbname)
: env_(options.env),
dbname_(dbname),
db_options_(SanitizeOptions(dbname, options)),
stats_(db_options_.statistics.get()),
db_lock_(nullptr),
mutex_(options.use_adaptive_mutex),
shutting_down_(false),
bg_cv_(&mutex_),
logfile_number_(0),
log_empty_(true),
default_cf_handle_(nullptr),
total_log_size_(0),
max_total_in_memory_state_(0),
tmp_batch_(),
bg_schedule_needed_(false),
bg_compaction_scheduled_(0),
bg_manual_only_(0),
bg_flush_scheduled_(0),
manual_compaction_(nullptr),
disable_delete_obsolete_files_(0),
delete_obsolete_files_last_run_(options.env->NowMicros()),
last_stats_dump_time_microsec_(0),
flush_on_destroy_(false),
env_options_(options),
#ifndef ROCKSDB_LITE
wal_manager_(db_options_, env_options_),
#endif // ROCKSDB_LITE
bg_work_gate_closed_(false),
refitting_level_(false),
opened_successfully_(false) {
env_->GetAbsolutePath(dbname, &db_absolute_path_);
// Reserve ten files or so for other uses and give the rest to TableCache.
// Give a large number for setting of "infinite" open files.
const int table_cache_size = (db_options_.max_open_files == -1) ?
4194304 : db_options_.max_open_files - 10;
// Reserve ten files or so for other uses and give the rest to TableCache.
table_cache_ =
NewLRUCache(table_cache_size, db_options_.table_cache_numshardbits,
db_options_.table_cache_remove_scan_count_limit);
versions_.reset(new VersionSet(dbname_, &db_options_, env_options_,
table_cache_.get(), &write_controller_));
column_family_memtables_.reset(new ColumnFamilyMemTablesImpl(
versions_->GetColumnFamilySet(), &flush_scheduler_));
DumpRocksDBBuildVersion(db_options_.info_log.get());
DumpDBFileSummary(db_options_, dbname_);
db_options_.Dump(db_options_.info_log.get());
LogFlush(db_options_.info_log);
}
DBImpl::~DBImpl() {
mutex_.Lock();
if (flush_on_destroy_) {
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (!cfd->mem()->IsEmpty()) {
cfd->Ref();
mutex_.Unlock();
FlushMemTable(cfd, FlushOptions());
mutex_.Lock();
cfd->Unref();
}
}
versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
}
// Wait for background work to finish
shutting_down_.store(true, std::memory_order_release);
while (bg_compaction_scheduled_ || bg_flush_scheduled_) {
bg_cv_.Wait();
}
flush_scheduler_.Clear();
if (default_cf_handle_ != nullptr) {
// we need to delete handle outside of lock because it does its own locking
mutex_.Unlock();
delete default_cf_handle_;
mutex_.Lock();
}
// Clean up obsolete files due to SuperVersion release.
// (1) Need to delete to obsolete files before closing because RepairDB()
// scans all existing files in the file system and builds manifest file.
// Keeping obsolete files confuses the repair process.
// (2) Need to check if we Open()/Recover() the DB successfully before
// deleting because if VersionSet recover fails (may be due to corrupted
// manifest file), it is not able to identify live files correctly. As a
// result, all "live" files can get deleted by accident. However, corrupted
// manifest is recoverable by RepairDB().
if (opened_successfully_) {
JobContext job_context;
FindObsoleteFiles(&job_context, true);
// manifest number starting from 2
job_context.manifest_file_number = 1;
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
}
// versions need to be destroyed before table_cache since it can hold
// references to table_cache.
versions_.reset();
mutex_.Unlock();
if (db_lock_ != nullptr) {
env_->UnlockFile(db_lock_);
}
LogFlush(db_options_.info_log);
}
Status DBImpl::NewDB() {
VersionEdit new_db;
new_db.SetLogNumber(0);
new_db.SetNextFile(2);
new_db.SetLastSequence(0);
Log(db_options_.info_log, "Creating manifest 1 \n");
const std::string manifest = DescriptorFileName(dbname_, 1);
unique_ptr<WritableFile> file;
Status s = env_->NewWritableFile(
manifest, &file, env_->OptimizeForManifestWrite(env_options_));
if (!s.ok()) {
return s;
}
file->SetPreallocationBlockSize(db_options_.manifest_preallocation_size);
{
log::Writer log(std::move(file));
std::string record;
new_db.EncodeTo(&record);
s = log.AddRecord(record);
}
if (s.ok()) {
// Make "CURRENT" file that points to the new manifest file.
s = SetCurrentFile(env_, dbname_, 1, db_directory_.get());
} else {
env_->DeleteFile(manifest);
}
return s;
}
void DBImpl::MaybeIgnoreError(Status* s) const {
if (s->ok() || db_options_.paranoid_checks) {
// No change needed
} else {
Log(db_options_.info_log, "Ignoring error %s", s->ToString().c_str());
*s = Status::OK();
}
}
const Status DBImpl::CreateArchivalDirectory() {
if (db_options_.WAL_ttl_seconds > 0 || db_options_.WAL_size_limit_MB > 0) {
std::string archivalPath = ArchivalDirectory(db_options_.wal_dir);
return env_->CreateDirIfMissing(archivalPath);
}
return Status::OK();
}
void DBImpl::PrintStatistics() {
auto dbstats = db_options_.statistics.get();
if (dbstats) {
Log(db_options_.info_log,
"STATISTCS:\n %s",
dbstats->ToString().c_str());
}
}
void DBImpl::MaybeDumpStats() {
if (db_options_.stats_dump_period_sec == 0) return;
const uint64_t now_micros = env_->NowMicros();
if (last_stats_dump_time_microsec_ +
db_options_.stats_dump_period_sec * 1000000
<= now_micros) {
// Multiple threads could race in here simultaneously.
// However, the last one will update last_stats_dump_time_microsec_
// atomically. We could see more than one dump during one dump
// period in rare cases.
last_stats_dump_time_microsec_ = now_micros;
bool tmp1 = false;
bool tmp2 = false;
DBPropertyType cf_property_type =
GetPropertyType("rocksdb.cfstats", &tmp1, &tmp2);
DBPropertyType db_property_type =
GetPropertyType("rocksdb.dbstats", &tmp1, &tmp2);
std::string stats;
{
MutexLock l(&mutex_);
for (auto cfd : *versions_->GetColumnFamilySet()) {
cfd->internal_stats()->GetStringProperty(cf_property_type,
"rocksdb.cfstats", &stats);
}
default_cf_internal_stats_->GetStringProperty(db_property_type,
"rocksdb.dbstats", &stats);
}
Log(db_options_.info_log, "------- DUMPING STATS -------");
Log(db_options_.info_log, "%s", stats.c_str());
PrintStatistics();
}
}
// Returns the list of live files in 'sst_live' and the list
// of all files in the filesystem in 'candidate_files'.
// no_full_scan = true -- never do the full scan using GetChildren()
// force = false -- don't force the full scan, except every
// db_options_.delete_obsolete_files_period_micros
// force = true -- force the full scan
void DBImpl::FindObsoleteFiles(JobContext* job_context, bool force,
bool no_full_scan) {
mutex_.AssertHeld();
// if deletion is disabled, do nothing
if (disable_delete_obsolete_files_ > 0) {
return;
}
bool doing_the_full_scan = false;
// logic for figurint out if we're doing the full scan
if (no_full_scan) {
doing_the_full_scan = false;
} else if (force || db_options_.delete_obsolete_files_period_micros == 0) {
doing_the_full_scan = true;
} else {
const uint64_t now_micros = env_->NowMicros();
if (delete_obsolete_files_last_run_ +
db_options_.delete_obsolete_files_period_micros < now_micros) {
doing_the_full_scan = true;
delete_obsolete_files_last_run_ = now_micros;
}
}
// get obsolete files
versions_->GetObsoleteFiles(&job_context->sst_delete_files);
// store the current filenum, lognum, etc
job_context->manifest_file_number = versions_->ManifestFileNumber();
job_context->pending_manifest_file_number =
versions_->PendingManifestFileNumber();
job_context->log_number = versions_->MinLogNumber();
job_context->prev_log_number = versions_->PrevLogNumber();
if (!doing_the_full_scan && !job_context->HaveSomethingToDelete()) {
// avoid filling up sst_live if we're sure that we
// are not going to do the full scan and that we don't have
// anything to delete at the moment
return;
}
// don't delete live files
for (auto pair : pending_outputs_) {
job_context->sst_live.emplace_back(pair.first, pair.second, 0);
}
versions_->AddLiveFiles(&job_context->sst_live);
if (doing_the_full_scan) {
for (uint32_t path_id = 0;
path_id < db_options_.db_paths.size(); path_id++) {
// set of all files in the directory. We'll exclude files that are still
// alive in the subsequent processings.
std::vector<std::string> files;
env_->GetChildren(db_options_.db_paths[path_id].path,
&files); // Ignore errors
for (std::string file : files) {
// TODO(icanadi) clean up this mess to avoid having one-off "/" prefixes
job_context->candidate_files.emplace_back("/" + file, path_id);
}
}
//Add log files in wal_dir
if (db_options_.wal_dir != dbname_) {
std::vector<std::string> log_files;
env_->GetChildren(db_options_.wal_dir, &log_files); // Ignore errors
for (std::string log_file : log_files) {
job_context->candidate_files.emplace_back(log_file, 0);
}
}
// Add info log files in db_log_dir
if (!db_options_.db_log_dir.empty() && db_options_.db_log_dir != dbname_) {
std::vector<std::string> info_log_files;
// Ignore errors
env_->GetChildren(db_options_.db_log_dir, &info_log_files);
for (std::string log_file : info_log_files) {
job_context->candidate_files.emplace_back(log_file, 0);
}
}
}
}
namespace {
bool CompareCandidateFile(const JobContext::CandidateFileInfo& first,
const JobContext::CandidateFileInfo& second) {
if (first.file_name > second.file_name) {
return true;
} else if (first.file_name < second.file_name) {
return false;
} else {
return (first.path_id > second.path_id);
}
}
}; // namespace
// Diffs the files listed in filenames and those that do not
// belong to live files are posibly removed. Also, removes all the
// files in sst_delete_files and log_delete_files.
// It is not necessary to hold the mutex when invoking this method.
void DBImpl::PurgeObsoleteFiles(const JobContext& state) {
// we'd better have sth to delete
assert(state.HaveSomethingToDelete());
// this checks if FindObsoleteFiles() was run before. If not, don't do
// PurgeObsoleteFiles(). If FindObsoleteFiles() was run, we need to also
// run PurgeObsoleteFiles(), even if disable_delete_obsolete_files_ is true
if (state.manifest_file_number == 0) {
return;
}
// Now, convert live list to an unordered map, WITHOUT mutex held;
// set is slow.
std::unordered_map<uint64_t, const FileDescriptor*> sst_live_map;
for (const FileDescriptor& fd : state.sst_live) {
sst_live_map[fd.GetNumber()] = &fd;
}
auto candidate_files = state.candidate_files;
candidate_files.reserve(candidate_files.size() +
state.sst_delete_files.size() +
state.log_delete_files.size());
// We may ignore the dbname when generating the file names.
const char* kDumbDbName = "";
for (auto file : state.sst_delete_files) {
candidate_files.emplace_back(
MakeTableFileName(kDumbDbName, file->fd.GetNumber()),
file->fd.GetPathId());
delete file;
}
for (auto file_num : state.log_delete_files) {
if (file_num > 0) {
candidate_files.emplace_back(LogFileName(kDumbDbName, file_num).substr(1),
0);
}
}
// dedup state.candidate_files so we don't try to delete the same
// file twice
sort(candidate_files.begin(), candidate_files.end(), CompareCandidateFile);
candidate_files.erase(unique(candidate_files.begin(), candidate_files.end()),
candidate_files.end());
std::vector<std::string> old_info_log_files;
InfoLogPrefix info_log_prefix(!db_options_.db_log_dir.empty(), dbname_);
for (const auto& candidate_file : candidate_files) {
std::string to_delete = candidate_file.file_name;
uint32_t path_id = candidate_file.path_id;
uint64_t number;
FileType type;
// Ignore file if we cannot recognize it.
if (!ParseFileName(to_delete, &number, info_log_prefix.prefix, &type)) {
continue;
}
bool keep = true;
switch (type) {
case kLogFile:
keep = ((number >= state.log_number) ||
(number == state.prev_log_number));
break;
case kDescriptorFile:
// Keep my manifest file, and any newer incarnations'
// (can happen during manifest roll)
keep = (number >= state.manifest_file_number);
break;
case kTableFile:
keep = (sst_live_map.find(number) != sst_live_map.end());
break;
case kTempFile:
// Any temp files that are currently being written to must
// be recorded in pending_outputs_, which is inserted into "live".
// Also, SetCurrentFile creates a temp file when writing out new
// manifest, which is equal to state.pending_manifest_file_number. We
// should not delete that file
keep = (sst_live_map.find(number) != sst_live_map.end()) ||
(number == state.pending_manifest_file_number);
break;
case kInfoLogFile:
keep = true;
if (number != 0) {
old_info_log_files.push_back(to_delete);
}
break;
case kCurrentFile:
case kDBLockFile:
case kIdentityFile:
case kMetaDatabase:
keep = true;
break;
}
if (keep) {
continue;
}
std::string fname;
if (type == kTableFile) {
// evict from cache
TableCache::Evict(table_cache_.get(), number);
fname = TableFileName(db_options_.db_paths, number, path_id);
} else {
fname = ((type == kLogFile) ?
db_options_.wal_dir : dbname_) + "/" + to_delete;
}
#ifdef ROCKSDB_LITE
Status s = env_->DeleteFile(fname);
Log(db_options_.info_log, "Delete %s type=%d #%" PRIu64 " -- %s\n",
fname.c_str(), type, number, s.ToString().c_str());
#else // not ROCKSDB_LITE
if (type == kLogFile && (db_options_.WAL_ttl_seconds > 0 ||
db_options_.WAL_size_limit_MB > 0)) {
wal_manager_.ArchiveWALFile(fname, number);
} else {
Status s = env_->DeleteFile(fname);
Log(db_options_.info_log, "Delete %s type=%d #%" PRIu64 " -- %s\n",
fname.c_str(), type, number, s.ToString().c_str());
}
#endif // ROCKSDB_LITE
}
// Delete old info log files.
size_t old_info_log_file_count = old_info_log_files.size();
if (old_info_log_file_count >= db_options_.keep_log_file_num) {
std::sort(old_info_log_files.begin(), old_info_log_files.end());
size_t end = old_info_log_file_count - db_options_.keep_log_file_num;
for (unsigned int i = 0; i <= end; i++) {
std::string& to_delete = old_info_log_files.at(i);
std::string full_path_to_delete = (db_options_.db_log_dir.empty() ?
dbname_ : db_options_.db_log_dir) + "/" + to_delete;
Log(db_options_.info_log, "Delete info log file %s\n",
full_path_to_delete.c_str());
Status s = env_->DeleteFile(full_path_to_delete);
if (!s.ok()) {
Log(db_options_.info_log, "Delete info log file %s FAILED -- %s\n",
to_delete.c_str(), s.ToString().c_str());
}
}
}
#ifndef ROCKSDB_LITE
wal_manager_.PurgeObsoleteWALFiles();
#endif // ROCKSDB_LITE
LogFlush(db_options_.info_log);
}
void DBImpl::DeleteObsoleteFiles() {
mutex_.AssertHeld();
JobContext job_context;
FindObsoleteFiles(&job_context, true);
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
}
Status DBImpl::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families, bool read_only,
bool error_if_log_file_exist) {
mutex_.AssertHeld();
bool is_new_db = false;
assert(db_lock_ == nullptr);
if (!read_only) {
// We call CreateDirIfMissing() as the directory may already exist (if we
// are reopening a DB), when this happens we don't want creating the
// directory to cause an error. However, we need to check if creating the
// directory fails or else we may get an obscure message about the lock
// file not existing. One real-world example of this occurring is if
// env->CreateDirIfMissing() doesn't create intermediate directories, e.g.
// when dbname_ is "dir/db" but when "dir" doesn't exist.
Status s = env_->CreateDirIfMissing(dbname_);
if (!s.ok()) {
return s;
}
for (auto& db_path : db_options_.db_paths) {
s = env_->CreateDirIfMissing(db_path.path);
if (!s.ok()) {
return s;
}
}
s = env_->NewDirectory(dbname_, &db_directory_);
if (!s.ok()) {
return s;
}
s = env_->LockFile(LockFileName(dbname_), &db_lock_);
if (!s.ok()) {
return s;
}
if (!env_->FileExists(CurrentFileName(dbname_))) {
if (db_options_.create_if_missing) {
s = NewDB();
is_new_db = true;
if (!s.ok()) {
return s;
}
} else {
return Status::InvalidArgument(
dbname_, "does not exist (create_if_missing is false)");
}
} else {
if (db_options_.error_if_exists) {
return Status::InvalidArgument(
dbname_, "exists (error_if_exists is true)");
}
}
// Check for the IDENTITY file and create it if not there
if (!env_->FileExists(IdentityFileName(dbname_))) {
s = SetIdentityFile(env_, dbname_);
if (!s.ok()) {
return s;
}
}
}
Status s = versions_->Recover(column_families, read_only);
if (db_options_.paranoid_checks && s.ok()) {
s = CheckConsistency();
}
if (s.ok()) {
SequenceNumber max_sequence(0);
default_cf_handle_ = new ColumnFamilyHandleImpl(
versions_->GetColumnFamilySet()->GetDefault(), this, &mutex_);
default_cf_internal_stats_ = default_cf_handle_->cfd()->internal_stats();
single_column_family_mode_ =
versions_->GetColumnFamilySet()->NumberOfColumnFamilies() == 1;
// Recover from all newer log files than the ones named in the
// descriptor (new log files may have been added by the previous
// incarnation without registering them in the descriptor).
//
// Note that PrevLogNumber() is no longer used, but we pay
// attention to it in case we are recovering a database
// produced by an older version of rocksdb.
const uint64_t min_log = versions_->MinLogNumber();
const uint64_t prev_log = versions_->PrevLogNumber();
std::vector<std::string> filenames;
s = env_->GetChildren(db_options_.wal_dir, &filenames);
if (!s.ok()) {
return s;
}
std::vector<uint64_t> logs;
for (size_t i = 0; i < filenames.size(); i++) {
uint64_t number;
FileType type;
if (ParseFileName(filenames[i], &number, &type) && type == kLogFile) {
if (is_new_db) {
return Status::Corruption(
"While creating a new Db, wal_dir contains "
"existing log file: ",
filenames[i]);
} else if ((number >= min_log) || (number == prev_log)) {
logs.push_back(number);
}
}
}
if (logs.size() > 0 && error_if_log_file_exist) {
return Status::Corruption(""
"The db was opened in readonly mode with error_if_log_file_exist"
"flag but a log file already exists");
}
if (!logs.empty()) {
// Recover in the order in which the logs were generated
std::sort(logs.begin(), logs.end());
s = RecoverLogFiles(logs, &max_sequence, read_only);
if (!s.ok()) {
// Clear memtables if recovery failed
for (auto cfd : *versions_->GetColumnFamilySet()) {
cfd->CreateNewMemtable(*cfd->GetLatestMutableCFOptions());
}
}
}
SetTickerCount(stats_, SEQUENCE_NUMBER, versions_->LastSequence());
}
// Initial value
max_total_in_memory_state_ = 0;
for (auto cfd : *versions_->GetColumnFamilySet()) {
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
max_total_in_memory_state_ += mutable_cf_options->write_buffer_size *
mutable_cf_options->max_write_buffer_number;
}
return s;
}
// REQUIRES: log_numbers are sorted in ascending order
Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
SequenceNumber* max_sequence, bool read_only) {
struct LogReporter : public log::Reader::Reporter {
Env* env;
Logger* info_log;
const char* fname;
Status* status; // nullptr if db_options_.paranoid_checks==false or
// db_options_.skip_log_error_on_recovery==true
virtual void Corruption(size_t bytes, const Status& s) {
Log(info_log, "%s%s: dropping %d bytes; %s",
(this->status == nullptr ? "(ignoring error) " : ""),
fname, static_cast<int>(bytes), s.ToString().c_str());
if (this->status != nullptr && this->status->ok()) *this->status = s;
}
};
mutex_.AssertHeld();
Status status;
std::unordered_map<int, VersionEdit> version_edits;
// no need to refcount because iteration is under mutex
for (auto cfd : *versions_->GetColumnFamilySet()) {
VersionEdit edit;
edit.SetColumnFamily(cfd->GetID());
version_edits.insert({cfd->GetID(), edit});
}
for (auto log_number : log_numbers) {
// The previous incarnation may not have written any MANIFEST
// records after allocating this log number. So we manually
// update the file number allocation counter in VersionSet.
versions_->MarkFileNumberUsed(log_number);
// Open the log file
std::string fname = LogFileName(db_options_.wal_dir, log_number);
unique_ptr<SequentialFile> file;
status = env_->NewSequentialFile(fname, &file, env_options_);
if (!status.ok()) {
MaybeIgnoreError(&status);
if (!status.ok()) {
return status;
} else {
// Fail with one log file, but that's ok.
// Try next one.
continue;
}
}
// Create the log reader.
LogReporter reporter;
reporter.env = env_;
reporter.info_log = db_options_.info_log.get();
reporter.fname = fname.c_str();
reporter.status =
(db_options_.paranoid_checks && !db_options_.skip_log_error_on_recovery
? &status
: nullptr);
// We intentially make log::Reader do checksumming even if
// paranoid_checks==false so that corruptions cause entire commits
// to be skipped instead of propagating bad information (like overly
// large sequence numbers).
log::Reader reader(std::move(file), &reporter, true /*checksum*/,
0 /*initial_offset*/);
Log(db_options_.info_log, "Recovering log #%" PRIu64 "", log_number);
// Read all the records and add to a memtable
std::string scratch;
Slice record;
WriteBatch batch;
while (reader.ReadRecord(&record, &scratch)) {
if (record.size() < 12) {
reporter.Corruption(record.size(),
Status::Corruption("log record too small"));
continue;
}
WriteBatchInternal::SetContents(&batch, record);
// If column family was not found, it might mean that the WAL write
// batch references to the column family that was dropped after the
// insert. We don't want to fail the whole write batch in that case --
// we just ignore the update.
// That's why we set ignore missing column families to true
status = WriteBatchInternal::InsertInto(
&batch, column_family_memtables_.get(), true, log_number);
MaybeIgnoreError(&status);
if (!status.ok()) {
return status;
}
const SequenceNumber last_seq = WriteBatchInternal::Sequence(&batch) +
WriteBatchInternal::Count(&batch) - 1;
if (last_seq > *max_sequence) {
*max_sequence = last_seq;
}
if (!read_only) {
// we can do this because this is called before client has access to the
// DB and there is only a single thread operating on DB
ColumnFamilyData* cfd;
while ((cfd = flush_scheduler_.GetNextColumnFamily()) != nullptr) {
cfd->Unref();
// If this asserts, it means that InsertInto failed in
// filtering updates to already-flushed column families
assert(cfd->GetLogNumber() <= log_number);
auto iter = version_edits.find(cfd->GetID());
assert(iter != version_edits.end());
VersionEdit* edit = &iter->second;
status = WriteLevel0TableForRecovery(cfd, cfd->mem(), edit);
if (!status.ok()) {
// Reflect errors immediately so that conditions like full
// file-systems cause the DB::Open() to fail.
return status;
}
cfd->CreateNewMemtable(*cfd->GetLatestMutableCFOptions());
}
}
}
flush_scheduler_.Clear();
if (versions_->LastSequence() < *max_sequence) {
versions_->SetLastSequence(*max_sequence);
}
}
if (!read_only) {
// no need to refcount since client still doesn't have access
// to the DB and can not drop column families while we iterate
auto max_log_number = log_numbers.back();
for (auto cfd : *versions_->GetColumnFamilySet()) {
auto iter = version_edits.find(cfd->GetID());
assert(iter != version_edits.end());
VersionEdit* edit = &iter->second;
if (cfd->GetLogNumber() > max_log_number) {
// Column family cfd has already flushed the data
// from all logs. Memtable has to be empty because
// we filter the updates based on log_number
// (in WriteBatch::InsertInto)
assert(cfd->mem()->GetFirstSequenceNumber() == 0);
assert(edit->NumEntries() == 0);
continue;
}
// flush the final memtable (if non-empty)
if (cfd->mem()->GetFirstSequenceNumber() != 0) {
status = WriteLevel0TableForRecovery(cfd, cfd->mem(), edit);
if (!status.ok()) {
// Recovery failed
break;
}
cfd->CreateNewMemtable(*cfd->GetLatestMutableCFOptions());
}
// write MANIFEST with update
// writing log_number in the manifest means that any log file
// with number strongly less than (log_number + 1) is already
// recovered and should be ignored on next reincarnation.
// Since we already recovered max_log_number, we want all logs
// with numbers `<= max_log_number` (includes this one) to be ignored
edit->SetLogNumber(max_log_number + 1);
// we must mark the next log number as used, even though it's
// not actually used. that is because VersionSet assumes
// VersionSet::next_file_number_ always to be strictly greater than any
// log number
versions_->MarkFileNumberUsed(max_log_number + 1);
status = versions_->LogAndApply(
cfd, *cfd->GetLatestMutableCFOptions(), edit, &mutex_);
if (!status.ok()) {
// Recovery failed
break;
}
}
}
return status;
}
Status DBImpl::WriteLevel0TableForRecovery(ColumnFamilyData* cfd, MemTable* mem,
VersionEdit* edit) {
mutex_.AssertHeld();
const uint64_t start_micros = env_->NowMicros();
FileMetaData meta;
meta.fd = FileDescriptor(versions_->NewFileNumber(), 0, 0);
pending_outputs_[meta.fd.GetNumber()] = 0; // path 0 for level 0 file.
ReadOptions ro;
ro.total_order_seek = true;
Arena arena;
Status s;
{
ScopedArenaIterator iter(mem->NewIterator(ro, &arena));
const SequenceNumber newest_snapshot = snapshots_.GetNewest();
const SequenceNumber earliest_seqno_in_memtable =
mem->GetFirstSequenceNumber();
Log(db_options_.info_log, "[%s] Level-0 table #%" PRIu64 ": started",
cfd->GetName().c_str(), meta.fd.GetNumber());
{
mutex_.Unlock();
s = BuildTable(
dbname_, env_, *cfd->ioptions(), env_options_, cfd->table_cache(),
iter.get(), &meta, cfd->internal_comparator(), newest_snapshot,
earliest_seqno_in_memtable, GetCompressionFlush(*cfd->ioptions()),
cfd->ioptions()->compression_opts, Env::IO_HIGH);
LogFlush(db_options_.info_log);
mutex_.Lock();
}
Log(db_options_.info_log,
"[%s] Level-0 table #%" PRIu64 ": %" PRIu64 " bytes %s",
cfd->GetName().c_str(), meta.fd.GetNumber(), meta.fd.GetFileSize(),
s.ToString().c_str());
}
pending_outputs_.erase(meta.fd.GetNumber());
// Note that if file_size is zero, the file has been deleted and
// should not be added to the manifest.
int level = 0;
if (s.ok() && meta.fd.GetFileSize() > 0) {
edit->AddFile(level, meta.fd.GetNumber(), meta.fd.GetPathId(),
meta.fd.GetFileSize(), meta.smallest, meta.largest,
meta.smallest_seqno, meta.largest_seqno);
}
InternalStats::CompactionStats stats(1);
stats.micros = env_->NowMicros() - start_micros;
stats.bytes_written = meta.fd.GetFileSize();
stats.files_out_levelnp1 = 1;
cfd->internal_stats()->AddCompactionStats(level, stats);
cfd->internal_stats()->AddCFStats(
InternalStats::BYTES_FLUSHED, meta.fd.GetFileSize());
RecordTick(stats_, COMPACT_WRITE_BYTES, meta.fd.GetFileSize());
return s;
}
Status DBImpl::FlushMemTableToOutputFile(
ColumnFamilyData* cfd, const MutableCFOptions& mutable_cf_options,
bool* madeProgress, JobContext* job_context, LogBuffer* log_buffer) {
mutex_.AssertHeld();
assert(cfd->imm()->size() != 0);
assert(cfd->imm()->IsFlushPending());
FlushJob flush_job(dbname_, cfd, db_options_, mutable_cf_options,
env_options_, versions_.get(), &mutex_, &shutting_down_,
&pending_outputs_, snapshots_.GetNewest(), job_context,
log_buffer, db_directory_.get(),
GetCompressionFlush(*cfd->ioptions()), stats_);
Status s = flush_job.Run();
if (s.ok()) {
InstallSuperVersionBackground(cfd, job_context, mutable_cf_options);
if (madeProgress) {
*madeProgress = 1;
}
VersionStorageInfo::LevelSummaryStorage tmp;
LogToBuffer(log_buffer, "[%s] Level summary: %s\n", cfd->GetName().c_str(),
cfd->current()->GetStorageInfo()->LevelSummary(&tmp));
if (disable_delete_obsolete_files_ == 0) {
// add to deletion state
while (alive_log_files_.size() &&
alive_log_files_.begin()->number < versions_->MinLogNumber()) {
const auto& earliest = *alive_log_files_.begin();
job_context->log_delete_files.push_back(earliest.number);
total_log_size_ -= earliest.size;
alive_log_files_.pop_front();
}
}
}
if (!s.ok() && !s.IsShutdownInProgress() && db_options_.paranoid_checks &&
bg_error_.ok()) {
// if a bad error happened (not ShutdownInProgress) and paranoid_checks is
// true, mark DB read-only
bg_error_ = s;
}
RecordFlushIOStats();
return s;
}
Status DBImpl::CompactRange(ColumnFamilyHandle* column_family,
const Slice* begin, const Slice* end,
bool reduce_level, int target_level,
uint32_t target_path_id) {
if (target_path_id >= db_options_.db_paths.size()) {
return Status::InvalidArgument("Invalid target path ID");
}
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
Status s = FlushMemTable(cfd, FlushOptions());
if (!s.ok()) {
LogFlush(db_options_.info_log);
return s;
}
int max_level_with_files = 0;
{
MutexLock l(&mutex_);
Version* base = cfd->current();
for (int level = 1; level < cfd->NumberLevels(); level++) {
if (base->GetStorageInfo()->OverlapInLevel(level, begin, end)) {
max_level_with_files = level;
}
}
}
for (int level = 0; level <= max_level_with_files; level++) {
// in case the compaction is unversal or if we're compacting the
// bottom-most level, the output level will be the same as input one.
// level 0 can never be the bottommost level (i.e. if all files are in level
// 0, we will compact to level 1)
if (cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO ||
(level == max_level_with_files && level > 0)) {
s = RunManualCompaction(cfd, level, level, target_path_id, begin, end);
} else {
s = RunManualCompaction(cfd, level, level + 1, target_path_id, begin,
end);
}
if (!s.ok()) {
LogFlush(db_options_.info_log);
return s;
}
}
if (reduce_level) {
s = ReFitLevel(cfd, max_level_with_files, target_level);
}
LogFlush(db_options_.info_log);
{
MutexLock l(&mutex_);
// an automatic compaction that has been scheduled might have been
// preempted by the manual compactions. Need to schedule it back.
MaybeScheduleFlushOrCompaction();
}
return s;
}
bool DBImpl::SetOptions(ColumnFamilyHandle* column_family,
const std::unordered_map<std::string, std::string>& options_map) {
auto* cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family)->cfd();
if (options_map.empty()) {
Log(db_options_.info_log, "SetOptions() on column family [%s], empty input",
cfd->GetName().c_str());
return false;
}
MutableCFOptions new_options;
bool succeed = false;
{
MutexLock l(&mutex_);
if (cfd->SetOptions(options_map)) {
new_options = *cfd->GetLatestMutableCFOptions();
succeed = true;
}
}
Log(db_options_.info_log, "SetOptions() on column family [%s], inputs:",
cfd->GetName().c_str());
for (const auto& o : options_map) {
Log(db_options_.info_log, "%s: %s\n", o.first.c_str(), o.second.c_str());
}
if (succeed) {
Log(db_options_.info_log, "[%s] SetOptions succeeded",
cfd->GetName().c_str());
new_options.Dump(db_options_.info_log.get());
} else {
Log(db_options_.info_log, "[%s] SetOptions failed",
cfd->GetName().c_str());
}
return succeed;
}
// return the same level if it cannot be moved
int DBImpl::FindMinimumEmptyLevelFitting(ColumnFamilyData* cfd,
const MutableCFOptions& mutable_cf_options, int level) {
mutex_.AssertHeld();
auto* vstorage = cfd->current()->GetStorageInfo();
int minimum_level = level;
for (int i = level - 1; i > 0; --i) {
// stop if level i is not empty
if (vstorage->NumLevelFiles(i) > 0) break;
// stop if level i is too small (cannot fit the level files)
if (mutable_cf_options.MaxBytesForLevel(i) <
vstorage->NumLevelBytes(level)) {
break;
}
minimum_level = i;
}
return minimum_level;
}
Status DBImpl::ReFitLevel(ColumnFamilyData* cfd, int level, int target_level) {
assert(level < cfd->NumberLevels());
SuperVersion* superversion_to_free = nullptr;
SuperVersion* new_superversion = new SuperVersion();
mutex_.Lock();
// only allow one thread refitting
if (refitting_level_) {
mutex_.Unlock();
Log(db_options_.info_log, "ReFitLevel: another thread is refitting");
delete new_superversion;
return Status::NotSupported("another thread is refitting");
}
refitting_level_ = true;
// wait for all background threads to stop
bg_work_gate_closed_ = true;
while (bg_compaction_scheduled_ > 0 || bg_flush_scheduled_) {
Log(db_options_.info_log,
"RefitLevel: waiting for background threads to stop: %d %d",
bg_compaction_scheduled_, bg_flush_scheduled_);
bg_cv_.Wait();
}
const MutableCFOptions mutable_cf_options =
*cfd->GetLatestMutableCFOptions();
// move to a smaller level
int to_level = target_level;
if (target_level < 0) {
to_level = FindMinimumEmptyLevelFitting(cfd, mutable_cf_options, level);
}
assert(to_level <= level);
Status status;
if (to_level < level) {
Log(db_options_.info_log, "[%s] Before refitting:\n%s",
cfd->GetName().c_str(), cfd->current()->DebugString().data());
VersionEdit edit;
edit.SetColumnFamily(cfd->GetID());
for (const auto& f : cfd->current()->GetStorageInfo()->files_[level]) {
edit.DeleteFile(level, f->fd.GetNumber());
edit.AddFile(to_level, f->fd.GetNumber(), f->fd.GetPathId(),
f->fd.GetFileSize(), f->smallest, f->largest,
f->smallest_seqno, f->largest_seqno);
}
Log(db_options_.info_log, "[%s] Apply version edit:\n%s",
cfd->GetName().c_str(), edit.DebugString().data());
status = versions_->LogAndApply(cfd,
mutable_cf_options, &edit, &mutex_, db_directory_.get());
superversion_to_free = InstallSuperVersion(
cfd, new_superversion, mutable_cf_options);
new_superversion = nullptr;
Log(db_options_.info_log, "[%s] LogAndApply: %s\n", cfd->GetName().c_str(),
status.ToString().data());
if (status.ok()) {
Log(db_options_.info_log, "[%s] After refitting:\n%s",
cfd->GetName().c_str(), cfd->current()->DebugString().data());
}
}
refitting_level_ = false;
bg_work_gate_closed_ = false;
mutex_.Unlock();
delete superversion_to_free;
delete new_superversion;
return status;
}
int DBImpl::NumberLevels(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
return cfh->cfd()->NumberLevels();
}
int DBImpl::MaxMemCompactionLevel(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
MutexLock l(&mutex_);
return cfh->cfd()->GetSuperVersion()->
mutable_cf_options.max_mem_compaction_level;
}
int DBImpl::Level0StopWriteTrigger(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
MutexLock l(&mutex_);
return cfh->cfd()->GetSuperVersion()->
mutable_cf_options.level0_stop_writes_trigger;
}
Status DBImpl::Flush(const FlushOptions& flush_options,
ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
return FlushMemTable(cfh->cfd(), flush_options);
}
SequenceNumber DBImpl::GetLatestSequenceNumber() const {
return versions_->LastSequence();
}
Status DBImpl::RunManualCompaction(ColumnFamilyData* cfd, int input_level,
int output_level, uint32_t output_path_id,
const Slice* begin, const Slice* end) {
assert(input_level >= 0);
InternalKey begin_storage, end_storage;
ManualCompaction manual;
manual.cfd = cfd;
manual.input_level = input_level;
manual.output_level = output_level;
manual.output_path_id = output_path_id;
manual.done = false;
manual.in_progress = false;
// For universal compaction, we enforce every manual compaction to compact
// all files.
if (begin == nullptr ||
cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
manual.begin = nullptr;
} else {
begin_storage = InternalKey(*begin, kMaxSequenceNumber, kValueTypeForSeek);
manual.begin = &begin_storage;
}
if (end == nullptr ||
cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
manual.end = nullptr;
} else {
end_storage = InternalKey(*end, 0, static_cast<ValueType>(0));
manual.end = &end_storage;
}
MutexLock l(&mutex_);
// When a manual compaction arrives, temporarily disable scheduling of
// non-manual compactions and wait until the number of scheduled compaction
// jobs drops to zero. This is needed to ensure that this manual compaction
// can compact any range of keys/files.
//
// bg_manual_only_ is non-zero when at least one thread is inside
// RunManualCompaction(), i.e. during that time no other compaction will
// get scheduled (see MaybeScheduleFlushOrCompaction).
//
// Note that the following loop doesn't stop more that one thread calling
// RunManualCompaction() from getting to the second while loop below.
// However, only one of them will actually schedule compaction, while
// others will wait on a condition variable until it completes.
++bg_manual_only_;
while (bg_compaction_scheduled_ > 0) {
Log(db_options_.info_log,
"[%s] Manual compaction waiting for all other scheduled background "
"compactions to finish",
cfd->GetName().c_str());
bg_cv_.Wait();
}
Log(db_options_.info_log, "[%s] Manual compaction starting",
cfd->GetName().c_str());
// We don't check bg_error_ here, because if we get the error in compaction,
// the compaction will set manual.status to bg_error_ and set manual.done to
// true.
while (!manual.done) {
assert(bg_manual_only_ > 0);
if (manual_compaction_ != nullptr) {
// Running either this or some other manual compaction
bg_cv_.Wait();
} else {
manual_compaction_ = &manual;
bg_compaction_scheduled_++;
env_->Schedule(&DBImpl::BGWorkCompaction, this, Env::Priority::LOW);
}
}
assert(!manual.in_progress);
assert(bg_manual_only_ > 0);
--bg_manual_only_;
return manual.status;
}
Status DBImpl::FlushMemTable(ColumnFamilyData* cfd,
const FlushOptions& flush_options) {
Status s;
{
WriteContext context;
MutexLock guard_lock(&mutex_);
if (cfd->imm()->size() == 0 && cfd->mem()->IsEmpty()) {
// Nothing to flush
return Status::OK();
}
WriteThread::Writer w(&mutex_);
s = write_thread_.EnterWriteThread(&w, 0);
assert(s.ok() && !w.done); // No timeout and nobody should do our job
// SetNewMemtableAndNewLogFile() will release and reacquire mutex
// during execution
s = SetNewMemtableAndNewLogFile(cfd, &context);
cfd->imm()->FlushRequested();
MaybeScheduleFlushOrCompaction();
write_thread_.ExitWriteThread(&w, &w, s);
}
if (s.ok() && flush_options.wait) {
// Wait until the compaction completes
s = WaitForFlushMemTable(cfd);
}
return s;
}
Status DBImpl::WaitForFlushMemTable(ColumnFamilyData* cfd) {
Status s;
// Wait until the compaction completes
MutexLock l(&mutex_);
while (cfd->imm()->size() > 0 && bg_error_.ok()) {
bg_cv_.Wait();
}
if (!bg_error_.ok()) {
s = bg_error_;
}
return s;
}
void DBImpl::MaybeScheduleFlushOrCompaction() {
mutex_.AssertHeld();
bg_schedule_needed_ = false;
if (bg_work_gate_closed_) {
// gate closed for backgrond work
} else if (shutting_down_.load(std::memory_order_acquire)) {
// DB is being deleted; no more background compactions
} else {
bool is_flush_pending = false;
// no need to refcount since we're under a mutex
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (cfd->imm()->IsFlushPending()) {
is_flush_pending = true;
}
}
if (is_flush_pending) {
// memtable flush needed
if (bg_flush_scheduled_ < db_options_.max_background_flushes) {
bg_flush_scheduled_++;
env_->Schedule(&DBImpl::BGWorkFlush, this, Env::Priority::HIGH);
} else if (db_options_.max_background_flushes > 0) {
bg_schedule_needed_ = true;
}
}
bool is_compaction_needed = false;
// no need to refcount since we're under a mutex
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (cfd->current()->GetStorageInfo()->NeedsCompaction()) {
is_compaction_needed = true;
break;
}
}
// Schedule BGWorkCompaction if there's a compaction pending (or a memtable
// flush, but the HIGH pool is not enabled)
// Do it only if max_background_compactions hasn't been reached and
// bg_manual_only_ == 0
if (!bg_manual_only_ &&
(is_compaction_needed ||
(is_flush_pending && db_options_.max_background_flushes == 0))) {
if (bg_compaction_scheduled_ < db_options_.max_background_compactions) {
bg_compaction_scheduled_++;
env_->Schedule(&DBImpl::BGWorkCompaction, this, Env::Priority::LOW);
} else {
bg_schedule_needed_ = true;
}
}
}
}
void DBImpl::RecordFlushIOStats() {
RecordTick(stats_, FLUSH_WRITE_BYTES, IOSTATS(bytes_written));
IOSTATS_RESET(bytes_written);
}
void DBImpl::RecordCompactionIOStats() {
RecordTick(stats_, COMPACT_READ_BYTES, IOSTATS(bytes_read));
IOSTATS_RESET(bytes_read);
RecordTick(stats_, COMPACT_WRITE_BYTES, IOSTATS(bytes_written));
IOSTATS_RESET(bytes_written);
}
void DBImpl::BGWorkFlush(void* db) {
IOSTATS_SET_THREAD_POOL_ID(Env::Priority::HIGH);
reinterpret_cast<DBImpl*>(db)->BackgroundCallFlush();
}
void DBImpl::BGWorkCompaction(void* db) {
IOSTATS_SET_THREAD_POOL_ID(Env::Priority::LOW);
reinterpret_cast<DBImpl*>(db)->BackgroundCallCompaction();
}
Status DBImpl::BackgroundFlush(bool* madeProgress, JobContext* job_context,
LogBuffer* log_buffer) {
mutex_.AssertHeld();
if (!bg_error_.ok()) {
return bg_error_;
}
// call_status is failure if at least one flush was a failure. even if
// flushing one column family reports a failure, we will continue flushing
// other column families. however, call_status will be a failure in that case.
Status call_status;
// refcounting in iteration
for (auto cfd : *versions_->GetColumnFamilySet()) {
cfd->Ref();
Status flush_status;
const MutableCFOptions mutable_cf_options =
*cfd->GetLatestMutableCFOptions();
while (flush_status.ok() && cfd->imm()->IsFlushPending()) {
LogToBuffer(
log_buffer,
"BackgroundCallFlush doing FlushMemTableToOutputFile with column "
"family [%s], flush slots available %d",
cfd->GetName().c_str(),
db_options_.max_background_flushes - bg_flush_scheduled_);
flush_status = FlushMemTableToOutputFile(
cfd, mutable_cf_options, madeProgress, job_context, log_buffer);
}
if (call_status.ok() && !flush_status.ok()) {
call_status = flush_status;
}
cfd->Unref();
}
versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
return call_status;
}
void DBImpl::BackgroundCallFlush() {
bool madeProgress = false;
JobContext job_context(true);
assert(bg_flush_scheduled_);
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL, db_options_.info_log.get());
{
MutexLock l(&mutex_);
Status s;
if (!shutting_down_.load(std::memory_order_acquire)) {
s = BackgroundFlush(&madeProgress, &job_context, &log_buffer);
if (!s.ok()) {
// Wait a little bit before retrying background compaction in
// case this is an environmental problem and we do not want to
// chew up resources for failed compactions for the duration of
// the problem.
uint64_t error_cnt =
default_cf_internal_stats_->BumpAndGetBackgroundErrorCount();
bg_cv_.SignalAll(); // In case a waiter can proceed despite the error
mutex_.Unlock();
Log(db_options_.info_log,
"Waiting after background flush error: %s"
"Accumulated background error counts: %" PRIu64,
s.ToString().c_str(), error_cnt);
log_buffer.FlushBufferToLog();
LogFlush(db_options_.info_log);
env_->SleepForMicroseconds(1000000);
mutex_.Lock();
}
}
// If !s.ok(), this means that Flush failed. In that case, we want
// to delete all obsolete files and we force FindObsoleteFiles()
FindObsoleteFiles(&job_context, !s.ok());
// delete unnecessary files if any, this is done outside the mutex
if (job_context.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
mutex_.Unlock();
// Have to flush the info logs before bg_flush_scheduled_--
// because if bg_flush_scheduled_ becomes 0 and the lock is
// released, the deconstructor of DB can kick in and destroy all the
// states of DB so info_log might not be available after that point.
// It also applies to access other states that DB owns.
log_buffer.FlushBufferToLog();
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
mutex_.Lock();
}
bg_flush_scheduled_--;
// Any time the mutex is released After finding the work to do, another
// thread might execute MaybeScheduleFlushOrCompaction(). It is possible
// that there is a pending job but it is not scheduled because of the
// max thread limit.
if (madeProgress || bg_schedule_needed_) {
MaybeScheduleFlushOrCompaction();
}
RecordFlushIOStats();
bg_cv_.SignalAll();
// IMPORTANT: there should be no code after calling SignalAll. This call may
// signal the DB destructor that it's OK to proceed with destruction. In
// that case, all DB variables will be dealloacated and referencing them
// will cause trouble.
}
}
void DBImpl::BackgroundCallCompaction() {
bool madeProgress = false;
JobContext job_context(true);
MaybeDumpStats();
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL, db_options_.info_log.get());
{
MutexLock l(&mutex_);
assert(bg_compaction_scheduled_);
Status s;
if (!shutting_down_.load(std::memory_order_acquire)) {
s = BackgroundCompaction(&madeProgress, &job_context, &log_buffer);
if (!s.ok()) {
// Wait a little bit before retrying background compaction in
// case this is an environmental problem and we do not want to
// chew up resources for failed compactions for the duration of
// the problem.
uint64_t error_cnt =
default_cf_internal_stats_->BumpAndGetBackgroundErrorCount();
bg_cv_.SignalAll(); // In case a waiter can proceed despite the error
mutex_.Unlock();
log_buffer.FlushBufferToLog();
Log(db_options_.info_log,
"Waiting after background compaction error: %s, "
"Accumulated background error counts: %" PRIu64,
s.ToString().c_str(), error_cnt);
LogFlush(db_options_.info_log);
env_->SleepForMicroseconds(1000000);
mutex_.Lock();
}
}
// If !s.ok(), this means that Compaction failed. In that case, we want
// to delete all obsolete files we might have created and we force
// FindObsoleteFiles(). This is because job_context does not
// catch all created files if compaction failed.
FindObsoleteFiles(&job_context, !s.ok());
// delete unnecessary files if any, this is done outside the mutex
if (job_context.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
mutex_.Unlock();
// Have to flush the info logs before bg_compaction_scheduled_--
// because if bg_flush_scheduled_ becomes 0 and the lock is
// released, the deconstructor of DB can kick in and destroy all the
// states of DB so info_log might not be available after that point.
// It also applies to access other states that DB owns.
log_buffer.FlushBufferToLog();
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
mutex_.Lock();
}
bg_compaction_scheduled_--;
versions_->GetColumnFamilySet()->FreeDeadColumnFamilies();
// Previous compaction may have produced too many files in a level,
// So reschedule another compaction if we made progress in the
// last compaction.
//
// Also, any time the mutex is released After finding the work to do,
// another thread might execute MaybeScheduleFlushOrCompaction(). It is
// possible that there is a pending job but it is not scheduled because of
// the max thread limit.
if (madeProgress || bg_schedule_needed_) {
MaybeScheduleFlushOrCompaction();
}
if (madeProgress || bg_compaction_scheduled_ == 0 || bg_manual_only_ > 0) {
// signal if
// * madeProgress -- need to wakeup DelayWrite
// * bg_compaction_scheduled_ == 0 -- need to wakeup ~DBImpl
// * bg_manual_only_ > 0 -- need to wakeup RunManualCompaction
// If none of this is true, there is no need to signal since nobody is
// waiting for it
bg_cv_.SignalAll();
}
// IMPORTANT: there should be no code after calling SignalAll. This call may
// signal the DB destructor that it's OK to proceed with destruction. In
// that case, all DB variables will be dealloacated and referencing them
// will cause trouble.
}
}
Status DBImpl::BackgroundCompaction(bool* madeProgress, JobContext* job_context,
LogBuffer* log_buffer) {
*madeProgress = false;
mutex_.AssertHeld();
bool is_manual = (manual_compaction_ != nullptr) &&
(manual_compaction_->in_progress == false);
if (!bg_error_.ok()) {
if (is_manual) {
manual_compaction_->status = bg_error_;
manual_compaction_->done = true;
manual_compaction_->in_progress = false;
manual_compaction_ = nullptr;
}
return bg_error_;
}
if (is_manual) {
// another thread cannot pick up the same work
manual_compaction_->in_progress = true;
} else if (manual_compaction_ != nullptr) {
// there should be no automatic compactions running when manual compaction
// is running
return Status::OK();
}
// FLUSH preempts compaction
Status flush_stat;
for (auto cfd : *versions_->GetColumnFamilySet()) {
const MutableCFOptions mutable_cf_options =
*cfd->GetLatestMutableCFOptions();
while (cfd->imm()->IsFlushPending()) {
LogToBuffer(
log_buffer,
"BackgroundCompaction doing FlushMemTableToOutputFile, "
"compaction slots available %d",
db_options_.max_background_compactions - bg_compaction_scheduled_);
cfd->Ref();
flush_stat = FlushMemTableToOutputFile(
cfd, mutable_cf_options, madeProgress, job_context, log_buffer);
cfd->Unref();
if (!flush_stat.ok()) {
if (is_manual) {
manual_compaction_->status = flush_stat;
manual_compaction_->done = true;
manual_compaction_->in_progress = false;
manual_compaction_ = nullptr;
}
return flush_stat;
}
}
}
// Compaction makes a copy of the latest MutableCFOptions. It should be used
// throughout the compaction procedure to make sure consistency. It will
// eventually be installed into SuperVersion
unique_ptr<Compaction> c;
InternalKey manual_end_storage;
InternalKey* manual_end = &manual_end_storage;
if (is_manual) {
ManualCompaction* m = manual_compaction_;
assert(m->in_progress);
c.reset(m->cfd->CompactRange(
*m->cfd->GetLatestMutableCFOptions(), m->input_level, m->output_level,
m->output_path_id, m->begin, m->end, &manual_end));
if (!c) {
m->done = true;
}
LogToBuffer(log_buffer,
"[%s] Manual compaction from level-%d to level-%d from %s .. "
"%s; will stop at %s\n",
m->cfd->GetName().c_str(), m->input_level, m->output_level,
(m->begin ? m->begin->DebugString().c_str() : "(begin)"),
(m->end ? m->end->DebugString().c_str() : "(end)"),
((m->done || manual_end == nullptr)
? "(end)"
: manual_end->DebugString().c_str()));
} else {
// no need to refcount in iteration since it's always under a mutex
for (auto cfd : *versions_->GetColumnFamilySet()) {
// Pick up latest mutable CF Options and use it throughout the
// compaction job
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
if (!mutable_cf_options->disable_auto_compactions) {
// NOTE: try to avoid unnecessary copy of MutableCFOptions if
// compaction is not necessary. Need to make sure mutex is held
// until we make a copy in the following code
c.reset(cfd->PickCompaction(*mutable_cf_options, log_buffer));
if (c != nullptr) {
// update statistics
MeasureTime(stats_, NUM_FILES_IN_SINGLE_COMPACTION,
c->inputs(0)->size());
break;
}
}
}
}
Status status;
if (!c) {
// Nothing to do
LogToBuffer(log_buffer, "Compaction nothing to do");
} else if (c->IsDeletionCompaction()) {
// TODO(icanadi) Do we want to honor snapshots here? i.e. not delete old
// file if there is alive snapshot pointing to it
assert(c->num_input_files(1) == 0);
assert(c->level() == 0);
assert(c->column_family_data()->ioptions()->compaction_style ==
kCompactionStyleFIFO);
for (const auto& f : *c->inputs(0)) {
c->edit()->DeleteFile(c->level(), f->fd.GetNumber());
}
status = versions_->LogAndApply(
c->column_family_data(), *c->mutable_cf_options(), c->edit(),
&mutex_, db_directory_.get());
InstallSuperVersionBackground(c->column_family_data(), job_context,
*c->mutable_cf_options());
LogToBuffer(log_buffer, "[%s] Deleted %d files\n",
c->column_family_data()->GetName().c_str(),
c->num_input_files(0));
c->ReleaseCompactionFiles(status);
*madeProgress = true;
} else if (!is_manual && c->IsTrivialMove()) {
// Move file to next level
assert(c->num_input_files(0) == 1);
FileMetaData* f = c->input(0, 0);
c->edit()->DeleteFile(c->level(), f->fd.GetNumber());
c->edit()->AddFile(c->level() + 1, f->fd.GetNumber(), f->fd.GetPathId(),
f->fd.GetFileSize(), f->smallest, f->largest,
f->smallest_seqno, f->largest_seqno);
status = versions_->LogAndApply(c->column_family_data(),
*c->mutable_cf_options(),
c->edit(), &mutex_, db_directory_.get());
// Use latest MutableCFOptions
InstallSuperVersionBackground(c->column_family_data(), job_context,
*c->mutable_cf_options());
VersionStorageInfo::LevelSummaryStorage tmp;
LogToBuffer(log_buffer, "[%s] Moved #%" PRIu64 " to level-%d %" PRIu64
" bytes %s: %s\n",
c->column_family_data()->GetName().c_str(), f->fd.GetNumber(),
c->level() + 1, f->fd.GetFileSize(), status.ToString().c_str(),
c->input_version()->GetStorageInfo()->LevelSummary(&tmp));
c->ReleaseCompactionFiles(status);
*madeProgress = true;
} else {
MaybeScheduleFlushOrCompaction(); // do more compaction work in parallel.
CompactionState* compact = new CompactionState(c.get());
status = DoCompactionWork(compact, *c->mutable_cf_options(), job_context,
log_buffer);
CleanupCompaction(compact, status);
c->ReleaseCompactionFiles(status);
c->ReleaseInputs();
*madeProgress = true;
}
c.reset();
if (status.ok()) {
// Done
} else if (status.IsShutdownInProgress()) {
// Ignore compaction errors found during shutting down
} else {
Log(InfoLogLevel::WARN_LEVEL, db_options_.info_log, "Compaction error: %s",
status.ToString().c_str());
if (db_options_.paranoid_checks && bg_error_.ok()) {
bg_error_ = status;
}
}
if (is_manual) {
ManualCompaction* m = manual_compaction_;
if (!status.ok()) {
m->status = status;
m->done = true;
}
// For universal compaction:
// Because universal compaction always happens at level 0, so one
// compaction will pick up all overlapped files. No files will be
// filtered out due to size limit and left for a successive compaction.
// So we can safely conclude the current compaction.
//
// Also note that, if we don't stop here, then the current compaction
// writes a new file back to level 0, which will be used in successive
// compaction. Hence the manual compaction will never finish.
//
// Stop the compaction if manual_end points to nullptr -- this means
// that we compacted the whole range. manual_end should always point
// to nullptr in case of universal compaction
if (manual_end == nullptr) {
m->done = true;
}
if (!m->done) {
// We only compacted part of the requested range. Update *m
// to the range that is left to be compacted.
// Universal and FIFO compactions should always compact the whole range
assert(m->cfd->ioptions()->compaction_style != kCompactionStyleUniversal);
assert(m->cfd->ioptions()->compaction_style != kCompactionStyleFIFO);
m->tmp_storage = *manual_end;
m->begin = &m->tmp_storage;
}
m->in_progress = false; // not being processed anymore
manual_compaction_ = nullptr;
}
return status;
}
void DBImpl::CleanupCompaction(CompactionState* compact, Status status) {
mutex_.AssertHeld();
if (compact->builder != nullptr) {
// May happen if we get a shutdown call in the middle of compaction
compact->builder->Abandon();
compact->builder.reset();
} else {
assert(!status.ok() || compact->outfile == nullptr);
}
for (size_t i = 0; i < compact->outputs.size(); i++) {
const CompactionState::Output& out = compact->outputs[i];
pending_outputs_.erase(out.number);
// If this file was inserted into the table cache then remove
// them here because this compaction was not committed.
if (!status.ok()) {
TableCache::Evict(table_cache_.get(), out.number);
}
}
delete compact;
}
// Allocate the file numbers for the output file. We allocate as
// many output file numbers as there are files in level+1 (at least one)
// Insert them into pending_outputs so that they do not get deleted.
void DBImpl::AllocateCompactionOutputFileNumbers(CompactionState* compact) {
mutex_.AssertHeld();
assert(compact != nullptr);
assert(compact->builder == nullptr);
int filesNeeded = compact->compaction->num_input_files(1);
for (int i = 0; i < std::max(filesNeeded, 1); i++) {
uint64_t file_number = versions_->NewFileNumber();
pending_outputs_[file_number] = compact->compaction->GetOutputPathId();
compact->allocated_file_numbers.push_back(file_number);
}
}
// Frees up unused file number.
void DBImpl::ReleaseCompactionUnusedFileNumbers(CompactionState* compact) {
mutex_.AssertHeld();
for (const auto file_number : compact->allocated_file_numbers) {
pending_outputs_.erase(file_number);
}
}
Status DBImpl::OpenCompactionOutputFile(
CompactionState* compact, const MutableCFOptions& mutable_cf_options) {
assert(compact != nullptr);
assert(compact->builder == nullptr);
uint64_t file_number;
// If we have not yet exhausted the pre-allocated file numbers,
// then use the one from the front. Otherwise, we have to acquire
// the heavyweight lock and allocate a new file number.
if (!compact->allocated_file_numbers.empty()) {
file_number = compact->allocated_file_numbers.front();
compact->allocated_file_numbers.pop_front();
} else {
mutex_.Lock();
file_number = versions_->NewFileNumber();
pending_outputs_[file_number] = compact->compaction->GetOutputPathId();
mutex_.Unlock();
}
// Make the output file
std::string fname = TableFileName(db_options_.db_paths, file_number,
compact->compaction->GetOutputPathId());
Status s = env_->NewWritableFile(fname, &compact->outfile, env_options_);
if (!s.ok()) {
Log(InfoLogLevel::ERROR_LEVEL, db_options_.info_log,
"[%s] OpenCompactionOutputFiles for table #%" PRIu64 " "
"fails at NewWritableFile with status %s",
compact->compaction->column_family_data()->GetName().c_str(),
file_number, s.ToString().c_str());
LogFlush(db_options_.info_log);
return s;
}
CompactionState::Output out;
out.number = file_number;
out.path_id = compact->compaction->GetOutputPathId();
out.smallest.Clear();
out.largest.Clear();
out.smallest_seqno = out.largest_seqno = 0;
compact->outputs.push_back(out);
compact->outfile->SetIOPriority(Env::IO_LOW);
compact->outfile->SetPreallocationBlockSize(
compact->compaction->OutputFilePreallocationSize(mutable_cf_options));
ColumnFamilyData* cfd = compact->compaction->column_family_data();
compact->builder.reset(NewTableBuilder(
*cfd->ioptions(), cfd->internal_comparator(), compact->outfile.get(),
compact->compaction->OutputCompressionType(),
cfd->ioptions()->compression_opts));
LogFlush(db_options_.info_log);
return s;
}
Status DBImpl::FinishCompactionOutputFile(CompactionState* compact,
Iterator* input) {
assert(compact != nullptr);
assert(compact->outfile);
assert(compact->builder != nullptr);
const uint64_t output_number = compact->current_output()->number;
const uint32_t output_path_id = compact->current_output()->path_id;
assert(output_number != 0);
// Check for iterator errors
Status s = input->status();
const uint64_t current_entries = compact->builder->NumEntries();
if (s.ok()) {
s = compact->builder->Finish();
} else {
compact->builder->Abandon();
}
const uint64_t current_bytes = compact->builder->FileSize();
compact->current_output()->file_size = current_bytes;
compact->total_bytes += current_bytes;
compact->builder.reset();
// Finish and check for file errors
if (s.ok() && !db_options_.disableDataSync) {
if (db_options_.use_fsync) {
StopWatch sw(env_, stats_, COMPACTION_OUTFILE_SYNC_MICROS);
s = compact->outfile->Fsync();
} else {
StopWatch sw(env_, stats_, COMPACTION_OUTFILE_SYNC_MICROS);
s = compact->outfile->Sync();
}
}
if (s.ok()) {
s = compact->outfile->Close();
}
compact->outfile.reset();
if (s.ok() && current_entries > 0) {
// Verify that the table is usable
ColumnFamilyData* cfd = compact->compaction->column_family_data();
FileDescriptor fd(output_number, output_path_id, current_bytes);
Iterator* iter = cfd->table_cache()->NewIterator(
ReadOptions(), env_options_, cfd->internal_comparator(), fd);
s = iter->status();
delete iter;
if (s.ok()) {
Log(db_options_.info_log, "[%s] Generated table #%" PRIu64 ": %" PRIu64
" keys, %" PRIu64 " bytes",
cfd->GetName().c_str(), output_number, current_entries,
current_bytes);
}
}
return s;
}
Status DBImpl::InstallCompactionResults(CompactionState* compact,
const MutableCFOptions& mutable_cf_options, LogBuffer* log_buffer) {
mutex_.AssertHeld();
// paranoia: verify that the files that we started with
// still exist in the current version and in the same original level.
// This ensures that a concurrent compaction did not erroneously
// pick the same files to compact.
if (!versions_->VerifyCompactionFileConsistency(compact->compaction)) {
Log(db_options_.info_log, "[%s] Compaction %d@%d + %d@%d files aborted",
compact->compaction->column_family_data()->GetName().c_str(),
compact->compaction->num_input_files(0), compact->compaction->level(),
compact->compaction->num_input_files(1),
compact->compaction->output_level());
return Status::Corruption("Compaction input files inconsistent");
}
LogToBuffer(log_buffer, "[%s] Compacted %d@%d + %d@%d files => %lld bytes",
compact->compaction->column_family_data()->GetName().c_str(),
compact->compaction->num_input_files(0),
compact->compaction->level(),
compact->compaction->num_input_files(1),
compact->compaction->output_level(),
static_cast<long long>(compact->total_bytes));
// Add compaction outputs
compact->compaction->AddInputDeletions(compact->compaction->edit());
for (size_t i = 0; i < compact->outputs.size(); i++) {
const CompactionState::Output& out = compact->outputs[i];
compact->compaction->edit()->AddFile(compact->compaction->output_level(),
out.number, out.path_id, out.file_size,
out.smallest, out.largest,
out.smallest_seqno, out.largest_seqno);
}
return versions_->LogAndApply(compact->compaction->column_family_data(),
mutable_cf_options,
compact->compaction->edit(), &mutex_,
db_directory_.get());
}
// Given a sequence number, return the sequence number of the
// earliest snapshot that this sequence number is visible in.
// The snapshots themselves are arranged in ascending order of
// sequence numbers.
// Employ a sequential search because the total number of
// snapshots are typically small.
inline SequenceNumber DBImpl::findEarliestVisibleSnapshot(
SequenceNumber in, std::vector<SequenceNumber>& snapshots,
SequenceNumber* prev_snapshot) {
SequenceNumber prev __attribute__((unused)) = 0;
for (const auto cur : snapshots) {
assert(prev <= cur);
if (cur >= in) {
*prev_snapshot = prev;
return cur;
}
prev = cur; // assignment
assert(prev);
}
Log(db_options_.info_log,
"Looking for seqid %" PRIu64 " but maxseqid is %" PRIu64 "", in,
snapshots[snapshots.size() - 1]);
assert(0);
return 0;
}
uint64_t DBImpl::CallFlushDuringCompaction(
ColumnFamilyData* cfd, const MutableCFOptions& mutable_cf_options,
JobContext* job_context, LogBuffer* log_buffer) {
if (db_options_.max_background_flushes > 0) {
// flush thread will take care of this
return 0;
}
if (cfd->imm()->imm_flush_needed.load(std::memory_order_relaxed)) {
const uint64_t imm_start = env_->NowMicros();
mutex_.Lock();
if (cfd->imm()->IsFlushPending()) {
cfd->Ref();
FlushMemTableToOutputFile(cfd, mutable_cf_options, nullptr, job_context,
log_buffer);
cfd->Unref();
bg_cv_.SignalAll(); // Wakeup DelayWrite() if necessary
}
mutex_.Unlock();
log_buffer->FlushBufferToLog();
return env_->NowMicros() - imm_start;
}
return 0;
}
Status DBImpl::ProcessKeyValueCompaction(
const MutableCFOptions& mutable_cf_options, bool is_snapshot_supported,
SequenceNumber visible_at_tip, SequenceNumber earliest_snapshot,
SequenceNumber latest_snapshot, JobContext* job_context,
bool bottommost_level, int64_t* imm_micros, Iterator* input,
CompactionState* compact, bool is_compaction_v2, int* num_output_records,
LogBuffer* log_buffer) {
assert(num_output_records != nullptr);
size_t combined_idx = 0;
Status status;
std::string compaction_filter_value;
ParsedInternalKey ikey;
IterKey current_user_key;
bool has_current_user_key = false;
IterKey delete_key;
SequenceNumber last_sequence_for_key __attribute__((unused)) =
kMaxSequenceNumber;
SequenceNumber visible_in_snapshot = kMaxSequenceNumber;
ColumnFamilyData* cfd = compact->compaction->column_family_data();
MergeHelper merge(
cfd->user_comparator(), cfd->ioptions()->merge_operator,
db_options_.info_log.get(), cfd->ioptions()->min_partial_merge_operands,
false /* internal key corruption is expected */);
auto compaction_filter = cfd->ioptions()->compaction_filter;
std::unique_ptr<CompactionFilter> compaction_filter_from_factory = nullptr;
if (!compaction_filter) {
auto context = compact->GetFilterContextV1();
compaction_filter_from_factory =
cfd->ioptions()->compaction_filter_factory->CreateCompactionFilter(
context);
compaction_filter = compaction_filter_from_factory.get();
}
int64_t key_drop_user = 0;
int64_t key_drop_newer_entry = 0;
int64_t key_drop_obsolete = 0;
int64_t loop_cnt = 0;
while (input->Valid() && !shutting_down_.load(std::memory_order_acquire) &&
!cfd->IsDropped() && status.ok()) {
if (++loop_cnt > 1000) {
if (key_drop_user > 0) {
RecordTick(stats_, COMPACTION_KEY_DROP_USER, key_drop_user);
key_drop_user = 0;
}
if (key_drop_newer_entry > 0) {
RecordTick(stats_, COMPACTION_KEY_DROP_NEWER_ENTRY,
key_drop_newer_entry);
key_drop_newer_entry = 0;
}
if (key_drop_obsolete > 0) {
RecordTick(stats_, COMPACTION_KEY_DROP_OBSOLETE, key_drop_obsolete);
key_drop_obsolete = 0;
}
RecordCompactionIOStats();
loop_cnt = 0;
}
// FLUSH preempts compaction
// TODO(icanadi) this currently only checks if flush is necessary on
// compacting column family. we should also check if flush is necessary on
// other column families, too
(*imm_micros) += CallFlushDuringCompaction(cfd, mutable_cf_options,
job_context, log_buffer);
Slice key;
Slice value;
// If is_compaction_v2 is on, kv-pairs are reset to the prefix batch.
// This prefix batch should contain results after calling
// compaction_filter_v2.
//
// If is_compaction_v2 is off, this function will go through all the
// kv-pairs in input.
if (!is_compaction_v2) {
key = input->key();
value = input->value();
} else {
if (combined_idx >= compact->combined_key_buf_.size()) {
break;
}
assert(combined_idx < compact->combined_key_buf_.size());
key = compact->combined_key_buf_[combined_idx];
value = compact->combined_value_buf_[combined_idx];
++combined_idx;
}
if (compact->compaction->ShouldStopBefore(key) &&
compact->builder != nullptr) {
status = FinishCompactionOutputFile(compact, input);
if (!status.ok()) {
break;
}
}
// Handle key/value, add to state, etc.
bool drop = false;
bool current_entry_is_merging = false;
if (!ParseInternalKey(key, &ikey)) {
// Do not hide error keys
// TODO: error key stays in db forever? Figure out the intention/rationale
// v10 error v8 : we cannot hide v8 even though it's pretty obvious.
current_user_key.Clear();
has_current_user_key = false;
last_sequence_for_key = kMaxSequenceNumber;
visible_in_snapshot = kMaxSequenceNumber;
} else {
if (!has_current_user_key ||
cfd->user_comparator()->Compare(ikey.user_key,
current_user_key.GetKey()) != 0) {
// First occurrence of this user key
current_user_key.SetKey(ikey.user_key);
has_current_user_key = true;
last_sequence_for_key = kMaxSequenceNumber;
visible_in_snapshot = kMaxSequenceNumber;
// apply the compaction filter to the first occurrence of the user key
if (compaction_filter && !is_compaction_v2 &&
ikey.type == kTypeValue &&
(visible_at_tip || ikey.sequence > latest_snapshot)) {
// If the user has specified a compaction filter and the sequence
// number is greater than any external snapshot, then invoke the
// filter.
// If the return value of the compaction filter is true, replace
// the entry with a delete marker.
bool value_changed = false;
compaction_filter_value.clear();
bool to_delete = compaction_filter->Filter(
compact->compaction->level(), ikey.user_key, value,
&compaction_filter_value, &value_changed);
if (to_delete) {
// make a copy of the original key and convert it to a delete
delete_key.SetInternalKey(ExtractUserKey(key), ikey.sequence,
kTypeDeletion);
// anchor the key again
key = delete_key.GetKey();
// needed because ikey is backed by key
ParseInternalKey(key, &ikey);
// no value associated with delete
value.clear();
++key_drop_user;
} else if (value_changed) {
value = compaction_filter_value;
}
}
}
// If there are no snapshots, then this kv affect visibility at tip.
// Otherwise, search though all existing snapshots to find
// the earlist snapshot that is affected by this kv.
SequenceNumber prev_snapshot = 0; // 0 means no previous snapshot
SequenceNumber visible = visible_at_tip ? visible_at_tip :
is_snapshot_supported ? findEarliestVisibleSnapshot(ikey.sequence,
compact->existing_snapshots, &prev_snapshot)
: 0;
if (visible_in_snapshot == visible) {
// If the earliest snapshot is which this key is visible in
// is the same as the visibily of a previous instance of the
// same key, then this kv is not visible in any snapshot.
// Hidden by an newer entry for same user key
// TODO: why not > ?
assert(last_sequence_for_key >= ikey.sequence);
drop = true; // (A)
++key_drop_newer_entry;
} else if (ikey.type == kTypeDeletion &&
ikey.sequence <= earliest_snapshot &&
compact->compaction->KeyNotExistsBeyondOutputLevel(ikey.user_key)) {
// For this user key:
// (1) there is no data in higher levels
// (2) data in lower levels will have larger sequence numbers
// (3) data in layers that are being compacted here and have
// smaller sequence numbers will be dropped in the next
// few iterations of this loop (by rule (A) above).
// Therefore this deletion marker is obsolete and can be dropped.
drop = true;
++key_drop_obsolete;
} else if (ikey.type == kTypeMerge) {
if (!merge.HasOperator()) {
LogToBuffer(log_buffer, "Options::merge_operator is null.");
status = Status::InvalidArgument(
"merge_operator is not properly initialized.");
break;
}
// We know the merge type entry is not hidden, otherwise we would
// have hit (A)
// We encapsulate the merge related state machine in a different
// object to minimize change to the existing flow. Turn out this
// logic could also be nicely re-used for memtable flush purge
// optimization in BuildTable.
int steps = 0;
merge.MergeUntil(input, prev_snapshot, bottommost_level,
db_options_.statistics.get(), &steps);
// Skip the Merge ops
combined_idx = combined_idx - 1 + steps;
current_entry_is_merging = true;
if (merge.IsSuccess()) {
// Successfully found Put/Delete/(end-of-key-range) while merging
// Get the merge result
key = merge.key();
ParseInternalKey(key, &ikey);
value = merge.value();
} else {
// Did not find a Put/Delete/(end-of-key-range) while merging
// We now have some stack of merge operands to write out.
// NOTE: key,value, and ikey are now referring to old entries.
// These will be correctly set below.
assert(!merge.keys().empty());
assert(merge.keys().size() == merge.values().size());
// Hack to make sure last_sequence_for_key is correct
ParseInternalKey(merge.keys().front(), &ikey);
}
}
last_sequence_for_key = ikey.sequence;
visible_in_snapshot = visible;
}
if (!drop) {
// We may write a single key (e.g.: for Put/Delete or successful merge).
// Or we may instead have to write a sequence/list of keys.
// We have to write a sequence iff we have an unsuccessful merge
bool has_merge_list = current_entry_is_merging && !merge.IsSuccess();
const std::deque<std::string>* keys = nullptr;
const std::deque<std::string>* values = nullptr;
std::deque<std::string>::const_reverse_iterator key_iter;
std::deque<std::string>::const_reverse_iterator value_iter;
if (has_merge_list) {
keys = &merge.keys();
values = &merge.values();
key_iter = keys->rbegin(); // The back (*rbegin()) is the first key
value_iter = values->rbegin();
key = Slice(*key_iter);
value = Slice(*value_iter);
}
// If we have a list of keys to write, traverse the list.
// If we have a single key to write, simply write that key.
while (true) {
// Invariant: key,value,ikey will always be the next entry to write
char* kptr = (char*)key.data();
std::string kstr;
// Zeroing out the sequence number leads to better compression.
// If this is the bottommost level (no files in lower levels)
// and the earliest snapshot is larger than this seqno
// then we can squash the seqno to zero.
if (bottommost_level && ikey.sequence < earliest_snapshot &&
ikey.type != kTypeMerge) {
assert(ikey.type != kTypeDeletion);
// make a copy because updating in place would cause problems
// with the priority queue that is managing the input key iterator
kstr.assign(key.data(), key.size());
kptr = (char *)kstr.c_str();
UpdateInternalKey(kptr, key.size(), (uint64_t)0, ikey.type);
}
Slice newkey(kptr, key.size());
assert((key.clear(), 1)); // we do not need 'key' anymore
// Open output file if necessary
if (compact->builder == nullptr) {
status = OpenCompactionOutputFile(compact, mutable_cf_options);
if (!status.ok()) {
break;
}
}
SequenceNumber seqno = GetInternalKeySeqno(newkey);
if (compact->builder->NumEntries() == 0) {
compact->current_output()->smallest.DecodeFrom(newkey);
compact->current_output()->smallest_seqno = seqno;
} else {
compact->current_output()->smallest_seqno =
std::min(compact->current_output()->smallest_seqno, seqno);
}
compact->current_output()->largest.DecodeFrom(newkey);
compact->builder->Add(newkey, value);
(*num_output_records)++,
compact->current_output()->largest_seqno =
std::max(compact->current_output()->largest_seqno, seqno);
// Close output file if it is big enough
if (compact->builder->FileSize() >=
compact->compaction->MaxOutputFileSize()) {
status = FinishCompactionOutputFile(compact, input);
if (!status.ok()) {
break;
}
}
// If we have a list of entries, move to next element
// If we only had one entry, then break the loop.
if (has_merge_list) {
++key_iter;
++value_iter;
// If at end of list
if (key_iter == keys->rend() || value_iter == values->rend()) {
// Sanity Check: if one ends, then both end
assert(key_iter == keys->rend() && value_iter == values->rend());
break;
}
// Otherwise not at end of list. Update key, value, and ikey.
key = Slice(*key_iter);
value = Slice(*value_iter);
ParseInternalKey(key, &ikey);
} else{
// Only had one item to begin with (Put/Delete)
break;
}
} // while (true)
} // if (!drop)
// MergeUntil has moved input to the next entry
if (!current_entry_is_merging) {
input->Next();
}
}
if (key_drop_user > 0) {
RecordTick(stats_, COMPACTION_KEY_DROP_USER, key_drop_user);
}
if (key_drop_newer_entry > 0) {
RecordTick(stats_, COMPACTION_KEY_DROP_NEWER_ENTRY, key_drop_newer_entry);
}
if (key_drop_obsolete > 0) {
RecordTick(stats_, COMPACTION_KEY_DROP_OBSOLETE, key_drop_obsolete);
}
RecordCompactionIOStats();
return status;
}
void DBImpl::CallCompactionFilterV2(CompactionState* compact,
CompactionFilterV2* compaction_filter_v2) {
if (compact == nullptr || compaction_filter_v2 == nullptr) {
return;
}
// Assemble slice vectors for user keys and existing values.
// We also keep track of our parsed internal key structs because
// we may need to access the sequence number in the event that
// keys are garbage collected during the filter process.
std::vector<ParsedInternalKey> ikey_buf;
std::vector<Slice> user_key_buf;
std::vector<Slice> existing_value_buf;
for (const auto& key : compact->key_str_buf_) {
ParsedInternalKey ikey;
ParseInternalKey(Slice(key), &ikey);
ikey_buf.emplace_back(ikey);
user_key_buf.emplace_back(ikey.user_key);
}
for (const auto& value : compact->existing_value_str_buf_) {
existing_value_buf.emplace_back(Slice(value));
}
// If the user has specified a compaction filter and the sequence
// number is greater than any external snapshot, then invoke the
// filter.
// If the return value of the compaction filter is true, replace
// the entry with a delete marker.
compact->to_delete_buf_ = compaction_filter_v2->Filter(
compact->compaction->level(),
user_key_buf, existing_value_buf,
&compact->new_value_buf_,
&compact->value_changed_buf_);
// new_value_buf_.size() <= to_delete__buf_.size(). "=" iff all
// kv-pairs in this compaction run needs to be deleted.
assert(compact->to_delete_buf_.size() ==
compact->key_str_buf_.size());
assert(compact->to_delete_buf_.size() ==
compact->existing_value_str_buf_.size());
assert(compact->to_delete_buf_.size() ==
compact->value_changed_buf_.size());
int new_value_idx = 0;
for (unsigned int i = 0; i < compact->to_delete_buf_.size(); ++i) {
if (compact->to_delete_buf_[i]) {
// update the string buffer directly
// the Slice buffer points to the updated buffer
UpdateInternalKey(&compact->key_str_buf_[i][0],
compact->key_str_buf_[i].size(),
ikey_buf[i].sequence,
kTypeDeletion);
// no value associated with delete
compact->existing_value_str_buf_[i].clear();
RecordTick(stats_, COMPACTION_KEY_DROP_USER);
} else if (compact->value_changed_buf_[i]) {
compact->existing_value_str_buf_[i] =
compact->new_value_buf_[new_value_idx++];
}
} // for
}
Status DBImpl::DoCompactionWork(CompactionState* compact,
const MutableCFOptions& mutable_cf_options,
JobContext* job_context,
LogBuffer* log_buffer) {
assert(compact);
compact->CleanupBatchBuffer();
compact->CleanupMergedBuffer();
// Generate file_levels_ for compaction berfore making Iterator
compact->compaction->GenerateFileLevels();
int64_t imm_micros = 0; // Micros spent doing imm_ compactions
ColumnFamilyData* cfd = compact->compaction->column_family_data();
LogToBuffer(
log_buffer,
"[%s] Compacting %d@%d + %d@%d files, score %.2f slots available %d",
cfd->GetName().c_str(), compact->compaction->num_input_files(0),
compact->compaction->level(), compact->compaction->num_input_files(1),
compact->compaction->output_level(), compact->compaction->score(),
db_options_.max_background_compactions - bg_compaction_scheduled_);
char scratch[2345];
compact->compaction->Summary(scratch, sizeof(scratch));
LogToBuffer(log_buffer, "[%s] Compaction start summary: %s\n",
cfd->GetName().c_str(), scratch);
assert(cfd->current()->GetStorageInfo()->NumLevelFiles(
compact->compaction->level()) > 0);
assert(compact->builder == nullptr);
assert(!compact->outfile);
SequenceNumber visible_at_tip = 0;
SequenceNumber earliest_snapshot;
SequenceNumber latest_snapshot = 0;
snapshots_.getAll(compact->existing_snapshots);
if (compact->existing_snapshots.size() == 0) {
// optimize for fast path if there are no snapshots
visible_at_tip = versions_->LastSequence();
earliest_snapshot = visible_at_tip;
} else {
latest_snapshot = compact->existing_snapshots.back();
// Add the current seqno as the 'latest' virtual
// snapshot to the end of this list.
compact->existing_snapshots.push_back(versions_->LastSequence());
earliest_snapshot = compact->existing_snapshots[0];
}
// Is this compaction producing files at the bottommost level?
bool bottommost_level = compact->compaction->BottomMostLevel();
// Allocate the output file numbers before we release the lock
AllocateCompactionOutputFileNumbers(compact);
bool is_snapshot_supported = IsSnapshotSupported();
// Release mutex while we're actually doing the compaction work
mutex_.Unlock();
log_buffer->FlushBufferToLog();
int num_output_records = 0;
const uint64_t start_micros = env_->NowMicros();
unique_ptr<Iterator> input(versions_->MakeInputIterator(compact->compaction));
input->SeekToFirst();
Status status;
ParsedInternalKey ikey;
std::unique_ptr<CompactionFilterV2> compaction_filter_from_factory_v2
= nullptr;
auto context = compact->GetFilterContext();
compaction_filter_from_factory_v2 =
cfd->ioptions()->compaction_filter_factory_v2->
CreateCompactionFilterV2(context);
auto compaction_filter_v2 =
compaction_filter_from_factory_v2.get();
if (!compaction_filter_v2) {
status = ProcessKeyValueCompaction(
mutable_cf_options, is_snapshot_supported, visible_at_tip,
earliest_snapshot, latest_snapshot, job_context, bottommost_level,
&imm_micros, input.get(), compact, false, &num_output_records,
log_buffer);
} else {
// temp_backup_input always point to the start of the current buffer
// temp_backup_input = backup_input;
// iterate through input,
// 1) buffer ineligible keys and value keys into 2 separate buffers;
// 2) send value_buffer to compaction filter and alternate the values;
// 3) merge value_buffer with ineligible_value_buffer;
// 4) run the modified "compaction" using the old for loop.
bool prefix_initialized = false;
shared_ptr<Iterator> backup_input(
versions_->MakeInputIterator(compact->compaction));
backup_input->SeekToFirst();
while (backup_input->Valid() &&
!shutting_down_.load(std::memory_order_acquire) &&
!cfd->IsDropped()) {
// FLUSH preempts compaction
// TODO(icanadi) this currently only checks if flush is necessary on
// compacting column family. we should also check if flush is necessary on
// other column families, too
imm_micros += CallFlushDuringCompaction(cfd, mutable_cf_options,
job_context, log_buffer);
Slice key = backup_input->key();
Slice value = backup_input->value();
if (!ParseInternalKey(key, &ikey)) {
// log error
Log(db_options_.info_log, "[%s] Failed to parse key: %s",
cfd->GetName().c_str(), key.ToString().c_str());
continue;
} else {
const SliceTransform* transformer =
cfd->ioptions()->compaction_filter_factory_v2->GetPrefixExtractor();
const auto key_prefix = transformer->Transform(ikey.user_key);
if (!prefix_initialized) {
compact->cur_prefix_ = key_prefix.ToString();
prefix_initialized = true;
}
// If the prefix remains the same, keep buffering
if (key_prefix.compare(Slice(compact->cur_prefix_)) == 0) {
// Apply the compaction filter V2 to all the kv pairs sharing
// the same prefix
if (ikey.type == kTypeValue &&
(visible_at_tip || ikey.sequence > latest_snapshot)) {
// Buffer all keys sharing the same prefix for CompactionFilterV2
// Iterate through keys to check prefix
compact->BufferKeyValueSlices(key, value);
} else {
// buffer ineligible keys
compact->BufferOtherKeyValueSlices(key, value);
}
backup_input->Next();
continue;
// finish changing values for eligible keys
} else {
// Now prefix changes, this batch is done.
// Call compaction filter on the buffered values to change the value
if (compact->key_str_buf_.size() > 0) {
CallCompactionFilterV2(compact, compaction_filter_v2);
}
compact->cur_prefix_ = key_prefix.ToString();
}
}
// Merge this batch of data (values + ineligible keys)
compact->MergeKeyValueSliceBuffer(&cfd->internal_comparator());
// Done buffering for the current prefix. Spit it out to disk
// Now just iterate through all the kv-pairs
status = ProcessKeyValueCompaction(
mutable_cf_options, is_snapshot_supported, visible_at_tip,
earliest_snapshot, latest_snapshot, job_context, bottommost_level,
&imm_micros, input.get(), compact, true, &num_output_records,
log_buffer);
if (!status.ok()) {
break;
}
// After writing the kv-pairs, we can safely remove the reference
// to the string buffer and clean them up
compact->CleanupBatchBuffer();
compact->CleanupMergedBuffer();
// Buffer the key that triggers the mismatch in prefix
if (ikey.type == kTypeValue &&
(visible_at_tip || ikey.sequence > latest_snapshot)) {
compact->BufferKeyValueSlices(key, value);
} else {
compact->BufferOtherKeyValueSlices(key, value);
}
backup_input->Next();
if (!backup_input->Valid()) {
// If this is the single last value, we need to merge it.
if (compact->key_str_buf_.size() > 0) {
CallCompactionFilterV2(compact, compaction_filter_v2);
}
compact->MergeKeyValueSliceBuffer(&cfd->internal_comparator());
status = ProcessKeyValueCompaction(
mutable_cf_options, is_snapshot_supported, visible_at_tip,
earliest_snapshot, latest_snapshot, job_context, bottommost_level,
&imm_micros, input.get(), compact, true, &num_output_records,
log_buffer);
compact->CleanupBatchBuffer();
compact->CleanupMergedBuffer();
}
} // done processing all prefix batches
// finish the last batch
if (compact->key_str_buf_.size() > 0) {
CallCompactionFilterV2(compact, compaction_filter_v2);
}
compact->MergeKeyValueSliceBuffer(&cfd->internal_comparator());
status = ProcessKeyValueCompaction(
mutable_cf_options, is_snapshot_supported, visible_at_tip,
earliest_snapshot, latest_snapshot, job_context, bottommost_level,
&imm_micros, input.get(), compact, true, &num_output_records,
log_buffer);
} // checking for compaction filter v2
if (status.ok() &&
(shutting_down_.load(std::memory_order_acquire) || cfd->IsDropped())) {
status = Status::ShutdownInProgress(
"Database shutdown or Column family drop during compaction");
}
if (status.ok() && compact->builder != nullptr) {
status = FinishCompactionOutputFile(compact, input.get());
}
if (status.ok()) {
status = input->status();
}
input.reset();
if (!db_options_.disableDataSync) {
db_directory_->Fsync();
}
InternalStats::CompactionStats stats(1);
stats.micros = env_->NowMicros() - start_micros - imm_micros;
stats.files_in_leveln = compact->compaction->num_input_files(0);
stats.files_in_levelnp1 = compact->compaction->num_input_files(1);
MeasureTime(stats_, COMPACTION_TIME, stats.micros);
int num_output_files = compact->outputs.size();
if (compact->builder != nullptr) {
// An error occurred so ignore the last output.
assert(num_output_files > 0);
--num_output_files;
}
stats.files_out_levelnp1 = num_output_files;
uint64_t num_input_records = 0;
for (int i = 0; i < compact->compaction->num_input_files(0); i++) {
stats.bytes_readn += compact->compaction->input(0, i)->fd.GetFileSize();
stats.num_input_records += compact->compaction->input(0, i)->num_entries;
num_input_records += compact->compaction->input(0, i)->num_entries;
}
for (int i = 0; i < compact->compaction->num_input_files(1); i++) {
stats.bytes_readnp1 += compact->compaction->input(1, i)->fd.GetFileSize();
num_input_records += compact->compaction->input(1, i)->num_entries;
}
for (int i = 0; i < num_output_files; i++) {
stats.bytes_written += compact->outputs[i].file_size;
}
stats.num_dropped_records =
static_cast<int>(num_input_records) - num_output_records;
RecordCompactionIOStats();
LogFlush(db_options_.info_log);
mutex_.Lock();
cfd->internal_stats()->AddCompactionStats(
compact->compaction->output_level(), stats);
// if there were any unused file number (mostly in case of
// compaction error), free up the entry from pending_putputs
ReleaseCompactionUnusedFileNumbers(compact);
if (status.ok()) {
status = InstallCompactionResults(compact, mutable_cf_options, log_buffer);
InstallSuperVersionBackground(cfd, job_context, mutable_cf_options);
}
VersionStorageInfo::LevelSummaryStorage tmp;
LogToBuffer(log_buffer,
"[%s] compacted to: %s, MB/sec: %.1f rd, %.1f wr, level %d, "
"files in(%d, %d) out(%d) "
"MB in(%.1f, %.1f) out(%.1f), read-write-amplify(%.1f) "
"write-amplify(%.1f) %s, records in: %d, records dropped: %d\n",
cfd->GetName().c_str(),
cfd->current()->GetStorageInfo()->LevelSummary(&tmp),
(stats.bytes_readn + stats.bytes_readnp1) /
static_cast<double>(stats.micros),
stats.bytes_written / static_cast<double>(stats.micros),
compact->compaction->output_level(), stats.files_in_leveln,
stats.files_in_levelnp1, stats.files_out_levelnp1,
stats.bytes_readn / 1048576.0, stats.bytes_readnp1 / 1048576.0,
stats.bytes_written / 1048576.0,
(stats.bytes_written + stats.bytes_readnp1 + stats.bytes_readn) /
(double)stats.bytes_readn,
stats.bytes_written / (double)stats.bytes_readn,
status.ToString().c_str(), stats.num_input_records,
stats.num_dropped_records);
return status;
}
namespace {
struct IterState {
IterState(DBImpl* db, port::Mutex* mu, SuperVersion* super_version)
: db(db), mu(mu), super_version(super_version) {}
DBImpl* db;
port::Mutex* mu;
SuperVersion* super_version;
};
static void CleanupIteratorState(void* arg1, void* arg2) {
IterState* state = reinterpret_cast<IterState*>(arg1);
if (state->super_version->Unref()) {
JobContext job_context;
state->mu->Lock();
state->super_version->Cleanup();
state->db->FindObsoleteFiles(&job_context, false, true);
state->mu->Unlock();
delete state->super_version;
if (job_context.HaveSomethingToDelete()) {
state->db->PurgeObsoleteFiles(job_context);
}
}
delete state;
}
} // namespace
Iterator* DBImpl::NewInternalIterator(const ReadOptions& read_options,
ColumnFamilyData* cfd,
SuperVersion* super_version,
Arena* arena) {
Iterator* internal_iter;
assert(arena != nullptr);
// Need to create internal iterator from the arena.
MergeIteratorBuilder merge_iter_builder(&cfd->internal_comparator(), arena);
// Collect iterator for mutable mem
merge_iter_builder.AddIterator(
super_version->mem->NewIterator(read_options, arena));
// Collect all needed child iterators for immutable memtables
super_version->imm->AddIterators(read_options, &merge_iter_builder);
// Collect iterators for files in L0 - Ln
super_version->current->AddIterators(read_options, env_options_,
&merge_iter_builder);
internal_iter = merge_iter_builder.Finish();
IterState* cleanup = new IterState(this, &mutex_, super_version);
internal_iter->RegisterCleanup(CleanupIteratorState, cleanup, nullptr);
return internal_iter;
}
ColumnFamilyHandle* DBImpl::DefaultColumnFamily() const {
return default_cf_handle_;
}
Status DBImpl::Get(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value) {
return GetImpl(read_options, column_family, key, value);
}
// JobContext gets created and destructed outside of the lock --
// we
// use this convinently to:
// * malloc one SuperVersion() outside of the lock -- new_superversion
// * delete SuperVersion()s outside of the lock -- superversions_to_free
//
// However, if InstallSuperVersion() gets called twice with the same
// job_context, we can't reuse the SuperVersion() that got
// malloced
// because
// first call already used it. In that rare case, we take a hit and create a
// new SuperVersion() inside of the mutex. We do similar thing
// for superversion_to_free
void DBImpl::InstallSuperVersionBackground(
ColumnFamilyData* cfd, JobContext* job_context,
const MutableCFOptions& mutable_cf_options) {
mutex_.AssertHeld();
SuperVersion* old_superversion = InstallSuperVersion(
cfd, job_context->new_superversion, mutable_cf_options);
job_context->new_superversion = nullptr;
job_context->superversions_to_free.push_back(old_superversion);
}
SuperVersion* DBImpl::InstallSuperVersion(
ColumnFamilyData* cfd, SuperVersion* new_sv,
const MutableCFOptions& mutable_cf_options) {
mutex_.AssertHeld();
auto* old = cfd->InstallSuperVersion(
new_sv ? new_sv : new SuperVersion(), &mutex_, mutable_cf_options);
// We want to schedule potential flush or compactions since new options may
// have been picked up in this new version. New options may cause flush
// compaction trigger condition to change.
MaybeScheduleFlushOrCompaction();
// Update max_total_in_memory_state_
auto old_memtable_size = 0;
if (old) {
old_memtable_size = old->mutable_cf_options.write_buffer_size *
old->mutable_cf_options.max_write_buffer_number;
}
max_total_in_memory_state_ =
max_total_in_memory_state_ - old_memtable_size +
mutable_cf_options.write_buffer_size *
mutable_cf_options.max_write_buffer_number;
return old;
}
Status DBImpl::GetImpl(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value, bool* value_found) {
StopWatch sw(env_, stats_, DB_GET);
PERF_TIMER_GUARD(get_snapshot_time);
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
SequenceNumber snapshot;
if (read_options.snapshot != nullptr) {
snapshot = reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_;
} else {
snapshot = versions_->LastSequence();
}
// Acquire SuperVersion
SuperVersion* sv = GetAndRefSuperVersion(cfd);
// Prepare to store a list of merge operations if merge occurs.
MergeContext merge_context;
Status s;
// First look in the memtable, then in the immutable memtable (if any).
// s is both in/out. When in, s could either be OK or MergeInProgress.
// merge_operands will contain the sequence of merges in the latter case.
LookupKey lkey(key, snapshot);
PERF_TIMER_STOP(get_snapshot_time);
if (sv->mem->Get(lkey, value, &s, &merge_context)) {
// Done
RecordTick(stats_, MEMTABLE_HIT);
} else if (sv->imm->Get(lkey, value, &s, &merge_context)) {
// Done
RecordTick(stats_, MEMTABLE_HIT);
} else {
PERF_TIMER_GUARD(get_from_output_files_time);
sv->current->Get(read_options, lkey, value, &s, &merge_context,
value_found);
RecordTick(stats_, MEMTABLE_MISS);
}
{
PERF_TIMER_GUARD(get_post_process_time);
ReturnAndCleanupSuperVersion(cfd, sv);
RecordTick(stats_, NUMBER_KEYS_READ);
RecordTick(stats_, BYTES_READ, value->size());
}
return s;
}
std::vector<Status> DBImpl::MultiGet(
const ReadOptions& read_options,
const std::vector<ColumnFamilyHandle*>& column_family,
const std::vector<Slice>& keys, std::vector<std::string>* values) {
StopWatch sw(env_, stats_, DB_MULTIGET);
PERF_TIMER_GUARD(get_snapshot_time);
SequenceNumber snapshot;
struct MultiGetColumnFamilyData {
ColumnFamilyData* cfd;
SuperVersion* super_version;
};
std::unordered_map<uint32_t, MultiGetColumnFamilyData*> multiget_cf_data;
// fill up and allocate outside of mutex
for (auto cf : column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(cf);
auto cfd = cfh->cfd();
if (multiget_cf_data.find(cfd->GetID()) == multiget_cf_data.end()) {
auto mgcfd = new MultiGetColumnFamilyData();
mgcfd->cfd = cfd;
multiget_cf_data.insert({cfd->GetID(), mgcfd});
}
}
mutex_.Lock();
if (read_options.snapshot != nullptr) {
snapshot = reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_;
} else {
snapshot = versions_->LastSequence();
}
for (auto mgd_iter : multiget_cf_data) {
mgd_iter.second->super_version =
mgd_iter.second->cfd->GetSuperVersion()->Ref();
}
mutex_.Unlock();
// Contain a list of merge operations if merge occurs.
MergeContext merge_context;
// Note: this always resizes the values array
size_t num_keys = keys.size();
std::vector<Status> stat_list(num_keys);
values->resize(num_keys);
// Keep track of bytes that we read for statistics-recording later
uint64_t bytes_read = 0;
PERF_TIMER_STOP(get_snapshot_time);
// For each of the given keys, apply the entire "get" process as follows:
// First look in the memtable, then in the immutable memtable (if any).
// s is both in/out. When in, s could either be OK or MergeInProgress.
// merge_operands will contain the sequence of merges in the latter case.
for (size_t i = 0; i < num_keys; ++i) {
merge_context.Clear();
Status& s = stat_list[i];
std::string* value = &(*values)[i];
LookupKey lkey(keys[i], snapshot);
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family[i]);
auto mgd_iter = multiget_cf_data.find(cfh->cfd()->GetID());
assert(mgd_iter != multiget_cf_data.end());
auto mgd = mgd_iter->second;
auto super_version = mgd->super_version;
if (super_version->mem->Get(lkey, value, &s, &merge_context)) {
// Done
} else if (super_version->imm->Get(lkey, value, &s, &merge_context)) {
// Done
} else {
PERF_TIMER_GUARD(get_from_output_files_time);
super_version->current->Get(read_options, lkey, value, &s,
&merge_context);
}
if (s.ok()) {
bytes_read += value->size();
}
}
// Post processing (decrement reference counts and record statistics)
PERF_TIMER_GUARD(get_post_process_time);
autovector<SuperVersion*> superversions_to_delete;
// TODO(icanadi) do we need lock here or just around Cleanup()?
mutex_.Lock();
for (auto mgd_iter : multiget_cf_data) {
auto mgd = mgd_iter.second;
if (mgd->super_version->Unref()) {
mgd->super_version->Cleanup();
superversions_to_delete.push_back(mgd->super_version);
}
}
mutex_.Unlock();
for (auto td : superversions_to_delete) {
delete td;
}
for (auto mgd : multiget_cf_data) {
delete mgd.second;
}
RecordTick(stats_, NUMBER_MULTIGET_CALLS);
RecordTick(stats_, NUMBER_MULTIGET_KEYS_READ, num_keys);
RecordTick(stats_, NUMBER_MULTIGET_BYTES_READ, bytes_read);
PERF_TIMER_STOP(get_post_process_time);
return stat_list;
}
Status DBImpl::CreateColumnFamily(const ColumnFamilyOptions& cf_options,
const std::string& column_family_name,
ColumnFamilyHandle** handle) {
*handle = nullptr;
MutexLock l(&mutex_);
if (versions_->GetColumnFamilySet()->GetColumnFamily(column_family_name) !=
nullptr) {
return Status::InvalidArgument("Column family already exists");
}
VersionEdit edit;
edit.AddColumnFamily(column_family_name);
uint32_t new_id = versions_->GetColumnFamilySet()->GetNextColumnFamilyID();
edit.SetColumnFamily(new_id);
edit.SetLogNumber(logfile_number_);
edit.SetComparatorName(cf_options.comparator->Name());
// LogAndApply will both write the creation in MANIFEST and create
// ColumnFamilyData object
Options opt(db_options_, cf_options);
Status s = versions_->LogAndApply(nullptr,
MutableCFOptions(opt, ImmutableCFOptions(opt)),
&edit, &mutex_, db_directory_.get(), false, &cf_options);
if (s.ok()) {
single_column_family_mode_ = false;
auto cfd =
versions_->GetColumnFamilySet()->GetColumnFamily(column_family_name);
assert(cfd != nullptr);
delete InstallSuperVersion(cfd, nullptr, *cfd->GetLatestMutableCFOptions());
*handle = new ColumnFamilyHandleImpl(cfd, this, &mutex_);
Log(db_options_.info_log, "Created column family [%s] (ID %u)",
column_family_name.c_str(), (unsigned)cfd->GetID());
} else {
Log(db_options_.info_log, "Creating column family [%s] FAILED -- %s",
column_family_name.c_str(), s.ToString().c_str());
}
return s;
}
Status DBImpl::DropColumnFamily(ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
if (cfd->GetID() == 0) {
return Status::InvalidArgument("Can't drop default column family");
}
VersionEdit edit;
edit.DropColumnFamily();
edit.SetColumnFamily(cfd->GetID());
Status s;
{
MutexLock l(&mutex_);
if (cfd->IsDropped()) {
s = Status::InvalidArgument("Column family already dropped!\n");
}
if (s.ok()) {
// we drop column family from a single write thread
WriteThread::Writer w(&mutex_);
s = write_thread_.EnterWriteThread(&w, 0);
assert(s.ok() && !w.done); // No timeout and nobody should do our job
s = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
&edit, &mutex_);
write_thread_.ExitWriteThread(&w, &w, s);
}
}
if (s.ok()) {
assert(cfd->IsDropped());
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
max_total_in_memory_state_ -= mutable_cf_options->write_buffer_size *
mutable_cf_options->max_write_buffer_number;
Log(db_options_.info_log, "Dropped column family with id %u\n",
cfd->GetID());
} else {
Log(db_options_.info_log,
"Dropping column family with id %u FAILED -- %s\n",
cfd->GetID(), s.ToString().c_str());
}
return s;
}
bool DBImpl::KeyMayExist(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
std::string* value, bool* value_found) {
if (value_found != nullptr) {
// falsify later if key-may-exist but can't fetch value
*value_found = true;
}
ReadOptions roptions = read_options;
roptions.read_tier = kBlockCacheTier; // read from block cache only
auto s = GetImpl(roptions, column_family, key, value, value_found);
// If block_cache is enabled and the index block of the table didn't
// not present in block_cache, the return value will be Status::Incomplete.
// In this case, key may still exist in the table.
return s.ok() || s.IsIncomplete();
}
Iterator* DBImpl::NewIterator(const ReadOptions& read_options,
ColumnFamilyHandle* column_family) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
if (read_options.tailing) {
#ifdef ROCKSDB_LITE
// not supported in lite version
return nullptr;
#else
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto iter = new ForwardIterator(this, read_options, cfd, sv);
return NewDBIterator(env_, *cfd->ioptions(), cfd->user_comparator(), iter,
kMaxSequenceNumber,
sv->mutable_cf_options.max_sequential_skip_in_iterations,
read_options.iterate_upper_bound);
#endif
} else {
SequenceNumber latest_snapshot = versions_->LastSequence();
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto snapshot =
read_options.snapshot != nullptr
? reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_
: latest_snapshot;
// Try to generate a DB iterator tree in continuous memory area to be
// cache friendly. Here is an example of result:
// +-------------------------------+
// | |
// | ArenaWrappedDBIter |
// | + |
// | +---> Inner Iterator ------------+
// | | | |
// | | +-- -- -- -- -- -- -- --+ |
// | +--- | Arena | |
// | | | |
// | Allocated Memory: | |
// | | +-------------------+ |
// | | | DBIter | <---+
// | | + |
// | | | +-> iter_ ------------+
// | | | | |
// | | +-------------------+ |
// | | | MergingIterator | <---+
// | | + |
// | | | +->child iter1 ------------+
// | | | | | |
// | | +->child iter2 ----------+ |
// | | | | | | |
// | | | +->child iter3 --------+ | |
// | | | | | |
// | | +-------------------+ | | |
// | | | Iterator1 | <--------+
// | | +-------------------+ | |
// | | | Iterator2 | <------+
// | | +-------------------+ |
// | | | Iterator3 | <----+
// | | +-------------------+
// | | |
// +-------+-----------------------+
//
// ArenaWrappedDBIter inlines an arena area where all the iterartor in the
// the iterator tree is allocated in the order of being accessed when
// querying.
// Laying out the iterators in the order of being accessed makes it more
// likely that any iterator pointer is close to the iterator it points to so
// that they are likely to be in the same cache line and/or page.
ArenaWrappedDBIter* db_iter = NewArenaWrappedDbIterator(
env_, *cfd->ioptions(), cfd->user_comparator(),
snapshot, sv->mutable_cf_options.max_sequential_skip_in_iterations,
read_options.iterate_upper_bound);
Iterator* internal_iter =
NewInternalIterator(read_options, cfd, sv, db_iter->GetArena());
db_iter->SetIterUnderDBIter(internal_iter);
return db_iter;
}
// To stop compiler from complaining
return nullptr;
}
Status DBImpl::NewIterators(
const ReadOptions& read_options,
const std::vector<ColumnFamilyHandle*>& column_families,
std::vector<Iterator*>* iterators) {
iterators->clear();
iterators->reserve(column_families.size());
if (read_options.tailing) {
#ifdef ROCKSDB_LITE
return Status::InvalidArgument(
"Tailing interator not supported in RocksDB lite");
#else
for (auto cfh : column_families) {
auto cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(cfh)->cfd();
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto iter = new ForwardIterator(this, read_options, cfd, sv);
iterators->push_back(
NewDBIterator(env_, *cfd->ioptions(), cfd->user_comparator(), iter,
kMaxSequenceNumber,
sv->mutable_cf_options.max_sequential_skip_in_iterations));
}
#endif
} else {
SequenceNumber latest_snapshot = versions_->LastSequence();
for (size_t i = 0; i < column_families.size(); ++i) {
auto* cfd = reinterpret_cast<ColumnFamilyHandleImpl*>(
column_families[i])->cfd();
SuperVersion* sv = cfd->GetReferencedSuperVersion(&mutex_);
auto snapshot =
read_options.snapshot != nullptr
? reinterpret_cast<const SnapshotImpl*>(
read_options.snapshot)->number_
: latest_snapshot;
ArenaWrappedDBIter* db_iter = NewArenaWrappedDbIterator(
env_, *cfd->ioptions(), cfd->user_comparator(), snapshot,
sv->mutable_cf_options.max_sequential_skip_in_iterations);
Iterator* internal_iter = NewInternalIterator(
read_options, cfd, sv, db_iter->GetArena());
db_iter->SetIterUnderDBIter(internal_iter);
iterators->push_back(db_iter);
}
}
return Status::OK();
}
bool DBImpl::IsSnapshotSupported() const {
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (!cfd->mem()->IsSnapshotSupported()) {
return false;
}
}
return true;
}
const Snapshot* DBImpl::GetSnapshot() {
MutexLock l(&mutex_);
// returns null if the underlying memtable does not support snapshot.
if (!IsSnapshotSupported()) return nullptr;
return snapshots_.New(versions_->LastSequence());
}
void DBImpl::ReleaseSnapshot(const Snapshot* s) {
MutexLock l(&mutex_);
snapshots_.Delete(reinterpret_cast<const SnapshotImpl*>(s));
}
// Convenience methods
Status DBImpl::Put(const WriteOptions& o, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& val) {
return DB::Put(o, column_family, key, val);
}
Status DBImpl::Merge(const WriteOptions& o, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& val) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
if (!cfh->cfd()->ioptions()->merge_operator) {
return Status::NotSupported("Provide a merge_operator when opening DB");
} else {
return DB::Merge(o, column_family, key, val);
}
}
Status DBImpl::Delete(const WriteOptions& write_options,
ColumnFamilyHandle* column_family, const Slice& key) {
return DB::Delete(write_options, column_family, key);
}
Status DBImpl::Write(const WriteOptions& write_options, WriteBatch* my_batch) {
if (my_batch == nullptr) {
return Status::Corruption("Batch is nullptr!");
}
PERF_TIMER_GUARD(write_pre_and_post_process_time);
WriteThread::Writer w(&mutex_);
w.batch = my_batch;
w.sync = write_options.sync;
w.disableWAL = write_options.disableWAL;
w.in_batch_group = false;
w.done = false;
w.timeout_hint_us = write_options.timeout_hint_us;
uint64_t expiration_time = 0;
bool has_timeout = false;
if (w.timeout_hint_us == 0) {
w.timeout_hint_us = WriteThread::kNoTimeOut;
} else {
expiration_time = env_->NowMicros() + w.timeout_hint_us;
has_timeout = true;
}
if (!write_options.disableWAL) {
RecordTick(stats_, WRITE_WITH_WAL);
default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_WITH_WAL, 1);
}
WriteContext context;
mutex_.Lock();
Status status = write_thread_.EnterWriteThread(&w, expiration_time);
assert(status.ok() || status.IsTimedOut());
if (status.IsTimedOut()) {
mutex_.Unlock();
RecordTick(stats_, WRITE_TIMEDOUT);
return Status::TimedOut();
}
if (w.done) { // write was done by someone else
default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_DONE_BY_OTHER,
1);
mutex_.Unlock();
RecordTick(stats_, WRITE_DONE_BY_OTHER);
return w.status;
}
RecordTick(stats_, WRITE_DONE_BY_SELF);
default_cf_internal_stats_->AddDBStats(InternalStats::WRITE_DONE_BY_SELF, 1);
// Once reaches this point, the current writer "w" will try to do its write
// job. It may also pick up some of the remaining writers in the "writers_"
// when it finds suitable, and finish them in the same write batch.
// This is how a write job could be done by the other writer.
assert(!single_column_family_mode_ ||
versions_->GetColumnFamilySet()->NumberOfColumnFamilies() == 1);
uint64_t max_total_wal_size = (db_options_.max_total_wal_size == 0)
? 4 * max_total_in_memory_state_
: db_options_.max_total_wal_size;
if (UNLIKELY(!single_column_family_mode_) &&
alive_log_files_.begin()->getting_flushed == false &&
total_log_size_ > max_total_wal_size) {
uint64_t flush_column_family_if_log_file = alive_log_files_.begin()->number;
alive_log_files_.begin()->getting_flushed = true;
Log(db_options_.info_log,
"Flushing all column families with data in WAL number %" PRIu64
". Total log size is %" PRIu64 " while max_total_wal_size is %" PRIu64,
flush_column_family_if_log_file, total_log_size_, max_total_wal_size);
// no need to refcount because drop is happening in write thread, so can't
// happen while we're in the write thread
for (auto cfd : *versions_->GetColumnFamilySet()) {
if (cfd->GetLogNumber() <= flush_column_family_if_log_file) {
status = SetNewMemtableAndNewLogFile(cfd, &context);
if (!status.ok()) {
break;
}
cfd->imm()->FlushRequested();
}
}
MaybeScheduleFlushOrCompaction();
}
if (UNLIKELY(status.ok() && !bg_error_.ok())) {
status = bg_error_;
}
if (UNLIKELY(status.ok() && !flush_scheduler_.Empty())) {
status = ScheduleFlushes(&context);
}
if (UNLIKELY(status.ok()) &&
(write_controller_.IsStopped() || write_controller_.GetDelay() > 0)) {
status = DelayWrite(expiration_time);
}
if (UNLIKELY(status.ok() && has_timeout &&
env_->NowMicros() > expiration_time)) {
status = Status::TimedOut();
}
uint64_t last_sequence = versions_->LastSequence();
WriteThread::Writer* last_writer = &w;
if (status.ok()) {
autovector<WriteBatch*> write_batch_group;
write_thread_.BuildBatchGroup(&last_writer, &write_batch_group);
// Add to log and apply to memtable. We can release the lock
// during this phase since &w is currently responsible for logging
// and protects against concurrent loggers and concurrent writes
// into memtables
{
mutex_.Unlock();
WriteBatch* updates = nullptr;
if (write_batch_group.size() == 1) {
updates = write_batch_group[0];
} else {
updates = &tmp_batch_;
for (size_t i = 0; i < write_batch_group.size(); ++i) {
WriteBatchInternal::Append(updates, write_batch_group[i]);
}
}
const SequenceNumber current_sequence = last_sequence + 1;
WriteBatchInternal::SetSequence(updates, current_sequence);
int my_batch_count = WriteBatchInternal::Count(updates);
last_sequence += my_batch_count;
const uint64_t batch_size = WriteBatchInternal::ByteSize(updates);
// Record statistics
RecordTick(stats_, NUMBER_KEYS_WRITTEN, my_batch_count);
RecordTick(stats_, BYTES_WRITTEN, batch_size);
if (write_options.disableWAL) {
flush_on_destroy_ = true;
}
PERF_TIMER_STOP(write_pre_and_post_process_time);
uint64_t log_size = 0;
if (!write_options.disableWAL) {
PERF_TIMER_GUARD(write_wal_time);
Slice log_entry = WriteBatchInternal::Contents(updates);
status = log_->AddRecord(log_entry);
total_log_size_ += log_entry.size();
alive_log_files_.back().AddSize(log_entry.size());
log_empty_ = false;
log_size = log_entry.size();
RecordTick(stats_, WAL_FILE_BYTES, log_size);
if (status.ok() && write_options.sync) {
RecordTick(stats_, WAL_FILE_SYNCED);
StopWatch sw(env_, stats_, WAL_FILE_SYNC_MICROS);
if (db_options_.use_fsync) {
status = log_->file()->Fsync();
} else {
status = log_->file()->Sync();
}
}
}
if (status.ok()) {
PERF_TIMER_GUARD(write_memtable_time);
status = WriteBatchInternal::InsertInto(
updates, column_family_memtables_.get(),
write_options.ignore_missing_column_families, 0, this, false);
// A non-OK status here indicates iteration failure (either in-memory
// writebatch corruption (very bad), or the client specified invalid
// column family). This will later on trigger bg_error_.
//
// Note that existing logic was not sound. Any partial failure writing
// into the memtable would result in a state that some write ops might
// have succeeded in memtable but Status reports error for all writes.
SetTickerCount(stats_, SEQUENCE_NUMBER, last_sequence);
}
PERF_TIMER_START(write_pre_and_post_process_time);
if (updates == &tmp_batch_) {
tmp_batch_.Clear();
}
mutex_.Lock();
// internal stats
default_cf_internal_stats_->AddDBStats(
InternalStats::BYTES_WRITTEN, batch_size);
default_cf_internal_stats_->AddDBStats(InternalStats::NUMBER_KEYS_WRITTEN,
my_batch_count);
if (!write_options.disableWAL) {
default_cf_internal_stats_->AddDBStats(
InternalStats::WAL_FILE_SYNCED, 1);
default_cf_internal_stats_->AddDBStats(
InternalStats::WAL_FILE_BYTES, log_size);
}
if (status.ok()) {
versions_->SetLastSequence(last_sequence);
}
}
}
if (db_options_.paranoid_checks && !status.ok() &&
!status.IsTimedOut() && bg_error_.ok()) {
bg_error_ = status; // stop compaction & fail any further writes
}
write_thread_.ExitWriteThread(&w, last_writer, status);
mutex_.Unlock();
if (status.IsTimedOut()) {
RecordTick(stats_, WRITE_TIMEDOUT);
}
return status;
}
// REQUIRES: mutex_ is held
// REQUIRES: this thread is currently at the front of the writer queue
Status DBImpl::DelayWrite(uint64_t expiration_time) {
StopWatch sw(env_, stats_, WRITE_STALL);
bool has_timeout = (expiration_time > 0);
auto delay = write_controller_.GetDelay();
if (write_controller_.IsStopped() == false && delay > 0) {
mutex_.Unlock();
env_->SleepForMicroseconds(delay);
mutex_.Lock();
}
while (bg_error_.ok() && write_controller_.IsStopped()) {
if (has_timeout) {
bg_cv_.TimedWait(expiration_time);
if (env_->NowMicros() > expiration_time) {
return Status::TimedOut();
}
} else {
bg_cv_.Wait();
}
}
return bg_error_;
}
Status DBImpl::ScheduleFlushes(WriteContext* context) {
bool schedule_bg_work = false;
ColumnFamilyData* cfd;
while ((cfd = flush_scheduler_.GetNextColumnFamily()) != nullptr) {
schedule_bg_work = true;
auto status = SetNewMemtableAndNewLogFile(cfd, context);
if (cfd->Unref()) {
delete cfd;
}
if (!status.ok()) {
return status;
}
}
if (schedule_bg_work) {
MaybeScheduleFlushOrCompaction();
}
return Status::OK();
}
// REQUIRES: mutex_ is held
// REQUIRES: this thread is currently at the front of the writer queue
Status DBImpl::SetNewMemtableAndNewLogFile(ColumnFamilyData* cfd,
WriteContext* context) {
mutex_.AssertHeld();
unique_ptr<WritableFile> lfile;
log::Writer* new_log = nullptr;
MemTable* new_mem = nullptr;
// Attempt to switch to a new memtable and trigger flush of old.
// Do this without holding the dbmutex lock.
assert(versions_->PrevLogNumber() == 0);
bool creating_new_log = !log_empty_;
uint64_t new_log_number =
creating_new_log ? versions_->NewFileNumber() : logfile_number_;
SuperVersion* new_superversion = nullptr;
const MutableCFOptions mutable_cf_options = *cfd->GetLatestMutableCFOptions();
mutex_.Unlock();
Status s;
{
if (creating_new_log) {
s = env_->NewWritableFile(
LogFileName(db_options_.wal_dir, new_log_number),
&lfile, env_->OptimizeForLogWrite(env_options_));
if (s.ok()) {
// Our final size should be less than write_buffer_size
// (compression, etc) but err on the side of caution.
lfile->SetPreallocationBlockSize(
1.1 * mutable_cf_options.write_buffer_size);
new_log = new log::Writer(std::move(lfile));
}
}
if (s.ok()) {
new_mem = new MemTable(cfd->internal_comparator(), *cfd->ioptions(),
mutable_cf_options);
new_superversion = new SuperVersion();
}
}
Log(db_options_.info_log,
"[%s] New memtable created with log file: #%" PRIu64 "\n",
cfd->GetName().c_str(), new_log_number);
mutex_.Lock();
if (!s.ok()) {
// how do we fail if we're not creating new log?
assert(creating_new_log);
// Avoid chewing through file number space in a tight loop.
versions_->ReuseLogFileNumber(new_log_number);
assert(!new_mem);
assert(!new_log);
return s;
}
if (creating_new_log) {
logfile_number_ = new_log_number;
assert(new_log != nullptr);
context->logs_to_free_.push_back(log_.release());
log_.reset(new_log);
log_empty_ = true;
alive_log_files_.push_back(LogFileNumberSize(logfile_number_));
for (auto cfd : *versions_->GetColumnFamilySet()) {
// all this is just optimization to delete logs that
// are no longer needed -- if CF is empty, that means it
// doesn't need that particular log to stay alive, so we just
// advance the log number. no need to persist this in the manifest
if (cfd->mem()->GetFirstSequenceNumber() == 0 &&
cfd->imm()->size() == 0) {
cfd->SetLogNumber(logfile_number_);
}
}
}
cfd->mem()->SetNextLogNumber(logfile_number_);
cfd->imm()->Add(cfd->mem());
new_mem->Ref();
cfd->SetMemtable(new_mem);
context->superversions_to_free_.push_back(
InstallSuperVersion(cfd, new_superversion, mutable_cf_options));
return s;
}
#ifndef ROCKSDB_LITE
Status DBImpl::GetPropertiesOfAllTables(ColumnFamilyHandle* column_family,
TablePropertiesCollection* props) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
// Increment the ref count
mutex_.Lock();
auto version = cfd->current();
version->Ref();
mutex_.Unlock();
auto s = version->GetPropertiesOfAllTables(props);
// Decrement the ref count
mutex_.Lock();
version->Unref();
mutex_.Unlock();
return s;
}
#endif // ROCKSDB_LITE
const std::string& DBImpl::GetName() const {
return dbname_;
}
Env* DBImpl::GetEnv() const {
return env_;
}
const Options& DBImpl::GetOptions(ColumnFamilyHandle* column_family) const {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
return *cfh->cfd()->options();
}
bool DBImpl::GetProperty(ColumnFamilyHandle* column_family,
const Slice& property, std::string* value) {
bool is_int_property = false;
bool need_out_of_mutex = false;
DBPropertyType property_type =
GetPropertyType(property, &is_int_property, &need_out_of_mutex);
value->clear();
if (is_int_property) {
uint64_t int_value;
bool ret_value = GetIntPropertyInternal(column_family, property_type,
need_out_of_mutex, &int_value);
if (ret_value) {
*value = std::to_string(int_value);
}
return ret_value;
} else {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
MutexLock l(&mutex_);
return cfd->internal_stats()->GetStringProperty(property_type, property,
value);
}
}
bool DBImpl::GetIntProperty(ColumnFamilyHandle* column_family,
const Slice& property, uint64_t* value) {
bool is_int_property = false;
bool need_out_of_mutex = false;
DBPropertyType property_type =
GetPropertyType(property, &is_int_property, &need_out_of_mutex);
if (!is_int_property) {
return false;
}
return GetIntPropertyInternal(column_family, property_type, need_out_of_mutex,
value);
}
bool DBImpl::GetIntPropertyInternal(ColumnFamilyHandle* column_family,
DBPropertyType property_type,
bool need_out_of_mutex, uint64_t* value) {
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
if (!need_out_of_mutex) {
MutexLock l(&mutex_);
return cfd->internal_stats()->GetIntProperty(property_type, value, this);
} else {
SuperVersion* sv = GetAndRefSuperVersion(cfd);
bool ret = cfd->internal_stats()->GetIntPropertyOutOfMutex(
property_type, sv->current, value);
ReturnAndCleanupSuperVersion(cfd, sv);
return ret;
}
}
SuperVersion* DBImpl::GetAndRefSuperVersion(ColumnFamilyData* cfd) {
// TODO(ljin): consider using GetReferencedSuperVersion() directly
return cfd->GetThreadLocalSuperVersion(&mutex_);
}
void DBImpl::ReturnAndCleanupSuperVersion(ColumnFamilyData* cfd,
SuperVersion* sv) {
bool unref_sv = !cfd->ReturnThreadLocalSuperVersion(sv);
if (unref_sv) {
// Release SuperVersion
if (sv->Unref()) {
{
MutexLock l(&mutex_);
sv->Cleanup();
}
delete sv;
RecordTick(stats_, NUMBER_SUPERVERSION_CLEANUPS);
}
RecordTick(stats_, NUMBER_SUPERVERSION_RELEASES);
}
}
void DBImpl::GetApproximateSizes(ColumnFamilyHandle* column_family,
const Range* range, int n, uint64_t* sizes) {
// TODO(opt): better implementation
Version* v;
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
{
MutexLock l(&mutex_);
v = cfd->current();
v->Ref();
}
for (int 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);
uint64_t start = versions_->ApproximateOffsetOf(v, k1);
uint64_t limit = versions_->ApproximateOffsetOf(v, k2);
sizes[i] = (limit >= start ? limit - start : 0);
}
{
MutexLock l(&mutex_);
v->Unref();
}
}
#ifndef ROCKSDB_LITE
Status DBImpl::GetUpdatesSince(
SequenceNumber seq, unique_ptr<TransactionLogIterator>* iter,
const TransactionLogIterator::ReadOptions& read_options) {
RecordTick(stats_, GET_UPDATES_SINCE_CALLS);
if (seq > versions_->LastSequence()) {
return Status::NotFound("Requested sequence not yet written in the db");
}
return wal_manager_.GetUpdatesSince(seq, iter, read_options, versions_.get());
}
Status DBImpl::DeleteFile(std::string name) {
uint64_t number;
FileType type;
WalFileType log_type;
if (!ParseFileName(name, &number, &type, &log_type) ||
(type != kTableFile && type != kLogFile)) {
Log(db_options_.info_log, "DeleteFile %s failed.\n", name.c_str());
return Status::InvalidArgument("Invalid file name");
}
Status status;
if (type == kLogFile) {
// Only allow deleting archived log files
if (log_type != kArchivedLogFile) {
Log(db_options_.info_log, "DeleteFile %s failed - not archived log.\n",
name.c_str());
return Status::NotSupported("Delete only supported for archived logs");
}
status = env_->DeleteFile(db_options_.wal_dir + "/" + name.c_str());
if (!status.ok()) {
Log(db_options_.info_log, "DeleteFile %s failed -- %s.\n",
name.c_str(), status.ToString().c_str());
}
return status;
}
int level;
FileMetaData* metadata;
ColumnFamilyData* cfd;
VersionEdit edit;
JobContext job_context(true);
{
MutexLock l(&mutex_);
status = versions_->GetMetadataForFile(number, &level, &metadata, &cfd);
if (!status.ok()) {
Log(db_options_.info_log, "DeleteFile %s failed. File not found\n",
name.c_str());
return Status::InvalidArgument("File not found");
}
assert(level < cfd->NumberLevels());
// If the file is being compacted no need to delete.
if (metadata->being_compacted) {
Log(db_options_.info_log,
"DeleteFile %s Skipped. File about to be compacted\n", name.c_str());
return Status::OK();
}
// Only the files in the last level can be deleted externally.
// This is to make sure that any deletion tombstones are not
// lost. Check that the level passed is the last level.
auto* vstoreage = cfd->current()->GetStorageInfo();
for (int i = level + 1; i < cfd->NumberLevels(); i++) {
if (vstoreage->NumLevelFiles(i) != 0) {
Log(db_options_.info_log,
"DeleteFile %s FAILED. File not in last level\n", name.c_str());
return Status::InvalidArgument("File not in last level");
}
}
// if level == 0, it has to be the oldest file
if (level == 0 && vstoreage->files_[0].back()->fd.GetNumber() != number) {
return Status::InvalidArgument("File in level 0, but not oldest");
}
edit.SetColumnFamily(cfd->GetID());
edit.DeleteFile(level, number);
status = versions_->LogAndApply(cfd, *cfd->GetLatestMutableCFOptions(),
&edit, &mutex_, db_directory_.get());
if (status.ok()) {
InstallSuperVersionBackground(cfd, &job_context,
*cfd->GetLatestMutableCFOptions());
}
FindObsoleteFiles(&job_context, false);
} // lock released here
LogFlush(db_options_.info_log);
// remove files outside the db-lock
if (job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(job_context);
}
{
MutexLock l(&mutex_);
// schedule flush if file deletion means we freed the space for flushes to
// continue
MaybeScheduleFlushOrCompaction();
}
return status;
}
void DBImpl::GetLiveFilesMetaData(std::vector<LiveFileMetaData>* metadata) {
MutexLock l(&mutex_);
versions_->GetLiveFilesMetaData(metadata);
}
#endif // ROCKSDB_LITE
Status DBImpl::CheckConsistency() {
mutex_.AssertHeld();
std::vector<LiveFileMetaData> metadata;
versions_->GetLiveFilesMetaData(&metadata);
std::string corruption_messages;
for (const auto& md : metadata) {
std::string file_path = md.db_path + "/" + md.name;
uint64_t fsize = 0;
Status s = env_->GetFileSize(file_path, &fsize);
if (!s.ok()) {
corruption_messages +=
"Can't access " + md.name + ": " + s.ToString() + "\n";
} else if (fsize != md.size) {
corruption_messages += "Sst file size mismatch: " + file_path +
". Size recorded in manifest " +
std::to_string(md.size) + ", actual size " +
std::to_string(fsize) + "\n";
}
}
if (corruption_messages.size() == 0) {
return Status::OK();
} else {
return Status::Corruption(corruption_messages);
}
}
Status DBImpl::GetDbIdentity(std::string& identity) {
std::string idfilename = IdentityFileName(dbname_);
unique_ptr<SequentialFile> idfile;
const EnvOptions soptions;
Status s = env_->NewSequentialFile(idfilename, &idfile, soptions);
if (!s.ok()) {
return s;
}
uint64_t file_size;
s = env_->GetFileSize(idfilename, &file_size);
if (!s.ok()) {
return s;
}
char buffer[file_size];
Slice id;
s = idfile->Read(file_size, &id, buffer);
if (!s.ok()) {
return s;
}
identity.assign(id.ToString());
// If last character is '\n' remove it from identity
if (identity.size() > 0 && identity.back() == '\n') {
identity.pop_back();
}
return s;
}
// Default implementations of convenience methods that subclasses of DB
// can call if they wish
Status DB::Put(const WriteOptions& opt, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
// Pre-allocate size of write batch conservatively.
// 8 bytes are taken by header, 4 bytes for count, 1 byte for type,
// and we allocate 11 extra bytes for key length, as well as value length.
WriteBatch batch(key.size() + value.size() + 24);
batch.Put(column_family, key, value);
return Write(opt, &batch);
}
Status DB::Delete(const WriteOptions& opt, ColumnFamilyHandle* column_family,
const Slice& key) {
WriteBatch batch;
batch.Delete(column_family, key);
return Write(opt, &batch);
}
Status DB::Merge(const WriteOptions& opt, ColumnFamilyHandle* column_family,
const Slice& key, const Slice& value) {
WriteBatch batch;
batch.Merge(column_family, key, value);
return Write(opt, &batch);
}
// Default implementation -- returns not supported status
Status DB::CreateColumnFamily(const ColumnFamilyOptions& cf_options,
const std::string& column_family_name,
ColumnFamilyHandle** handle) {
return Status::NotSupported("");
}
Status DB::DropColumnFamily(ColumnFamilyHandle* column_family) {
return Status::NotSupported("");
}
DB::~DB() { }
Status DB::Open(const Options& options, const std::string& dbname, DB** dbptr) {
DBOptions db_options(options);
ColumnFamilyOptions cf_options(options);
std::vector<ColumnFamilyDescriptor> column_families;
column_families.push_back(
ColumnFamilyDescriptor(kDefaultColumnFamilyName, cf_options));
std::vector<ColumnFamilyHandle*> handles;
Status s = DB::Open(db_options, dbname, column_families, &handles, dbptr);
if (s.ok()) {
assert(handles.size() == 1);
// i can delete the handle since DBImpl is always holding a reference to
// default column family
delete handles[0];
}
return s;
}
Status DB::Open(const DBOptions& db_options, const std::string& dbname,
const std::vector<ColumnFamilyDescriptor>& column_families,
std::vector<ColumnFamilyHandle*>* handles, DB** dbptr) {
Status s = SanitizeOptionsByTable(db_options, column_families);
if (!s.ok()) {
return s;
}
if (db_options.db_paths.size() > 1) {
for (auto& cfd : column_families) {
if (cfd.options.compaction_style != kCompactionStyleUniversal) {
return Status::NotSupported(
"More than one DB paths are only supported in "
"universal compaction style. ");
}
}
if (db_options.db_paths.size() > 4) {
return Status::NotSupported(
"More than four DB paths are not supported yet. ");
}
}
*dbptr = nullptr;
handles->clear();
size_t max_write_buffer_size = 0;
for (auto cf : column_families) {
max_write_buffer_size =
std::max(max_write_buffer_size, cf.options.write_buffer_size);
}
DBImpl* impl = new DBImpl(db_options, dbname);
s = impl->env_->CreateDirIfMissing(impl->db_options_.wal_dir);
if (s.ok()) {
for (auto db_path : impl->db_options_.db_paths) {
s = impl->env_->CreateDirIfMissing(db_path.path);
if (!s.ok()) {
break;
}
}
}
if (!s.ok()) {
delete impl;
return s;
}
s = impl->CreateArchivalDirectory();
if (!s.ok()) {
delete impl;
return s;
}
impl->mutex_.Lock();
// Handles create_if_missing, error_if_exists
s = impl->Recover(column_families);
if (s.ok()) {
uint64_t new_log_number = impl->versions_->NewFileNumber();
unique_ptr<WritableFile> lfile;
EnvOptions soptions(db_options);
s = impl->db_options_.env->NewWritableFile(
LogFileName(impl->db_options_.wal_dir, new_log_number), &lfile,
impl->db_options_.env->OptimizeForLogWrite(soptions));
if (s.ok()) {
lfile->SetPreallocationBlockSize(1.1 * max_write_buffer_size);
impl->logfile_number_ = new_log_number;
impl->log_.reset(new log::Writer(std::move(lfile)));
// set column family handles
for (auto cf : column_families) {
auto cfd =
impl->versions_->GetColumnFamilySet()->GetColumnFamily(cf.name);
if (cfd != nullptr) {
handles->push_back(
new ColumnFamilyHandleImpl(cfd, impl, &impl->mutex_));
} else {
if (db_options.create_missing_column_families) {
// missing column family, create it
ColumnFamilyHandle* handle;
impl->mutex_.Unlock();
s = impl->CreateColumnFamily(cf.options, cf.name, &handle);
impl->mutex_.Lock();
if (s.ok()) {
handles->push_back(handle);
} else {
break;
}
} else {
s = Status::InvalidArgument("Column family not found: ", cf.name);
break;
}
}
}
}
if (s.ok()) {
for (auto cfd : *impl->versions_->GetColumnFamilySet()) {
delete impl->InstallSuperVersion(
cfd, nullptr, *cfd->GetLatestMutableCFOptions());
}
impl->alive_log_files_.push_back(
DBImpl::LogFileNumberSize(impl->logfile_number_));
impl->DeleteObsoleteFiles();
impl->MaybeScheduleFlushOrCompaction();
s = impl->db_directory_->Fsync();
}
}
if (s.ok()) {
for (auto cfd : *impl->versions_->GetColumnFamilySet()) {
if (cfd->ioptions()->compaction_style == kCompactionStyleUniversal ||
cfd->ioptions()->compaction_style == kCompactionStyleFIFO) {
auto* vstorage = cfd->current()->GetStorageInfo();
for (int i = 1; i < vstorage->NumberLevels(); ++i) {
int num_files = vstorage->NumLevelFiles(i);
if (num_files > 0) {
s = Status::InvalidArgument(
"Not all files are at level 0. Cannot "
"open with universal or FIFO compaction style.");
break;
}
}
}
if (cfd->ioptions()->merge_operator != nullptr &&
!cfd->mem()->IsMergeOperatorSupported()) {
s = Status::InvalidArgument(
"The memtable of column family %s does not support merge operator "
"its options.merge_operator is non-null", cfd->GetName().c_str());
}
if (!s.ok()) {
break;
}
}
}
impl->mutex_.Unlock();
if (s.ok()) {
impl->opened_successfully_ = true;
*dbptr = impl;
} else {
for (auto h : *handles) {
delete h;
}
handles->clear();
delete impl;
}
return s;
}
Status DB::ListColumnFamilies(const DBOptions& db_options,
const std::string& name,
std::vector<std::string>* column_families) {
return VersionSet::ListColumnFamilies(column_families, name, db_options.env);
}
Snapshot::~Snapshot() {
}
Status DestroyDB(const std::string& dbname, const Options& options) {
const InternalKeyComparator comparator(options.comparator);
const Options& soptions(SanitizeOptions(dbname, &comparator, options));
Env* env = soptions.env;
std::vector<std::string> filenames;
std::vector<std::string> archiveFiles;
std::string archivedir = ArchivalDirectory(dbname);
// Ignore error in case directory does not exist
env->GetChildren(dbname, &filenames);
if (dbname != soptions.wal_dir) {
std::vector<std::string> logfilenames;
env->GetChildren(soptions.wal_dir, &logfilenames);
filenames.insert(filenames.end(), logfilenames.begin(), logfilenames.end());
archivedir = ArchivalDirectory(soptions.wal_dir);
}
if (filenames.empty()) {
return Status::OK();
}
FileLock* lock;
const std::string lockname = LockFileName(dbname);
Status result = env->LockFile(lockname, &lock);
if (result.ok()) {
uint64_t number;
FileType type;
InfoLogPrefix info_log_prefix(!options.db_log_dir.empty(), dbname);
for (size_t i = 0; i < filenames.size(); i++) {
if (ParseFileName(filenames[i], &number, info_log_prefix.prefix, &type) &&
type != kDBLockFile) { // Lock file will be deleted at end
Status del;
if (type == kMetaDatabase) {
del = DestroyDB(dbname + "/" + filenames[i], options);
} else if (type == kLogFile) {
del = env->DeleteFile(soptions.wal_dir + "/" + filenames[i]);
} else {
del = env->DeleteFile(dbname + "/" + filenames[i]);
}
if (result.ok() && !del.ok()) {
result = del;
}
}
}
for (auto& db_path : options.db_paths) {
env->GetChildren(db_path.path, &filenames);
uint64_t number;
FileType type;
for (size_t i = 0; i < filenames.size(); i++) {
if (ParseFileName(filenames[i], &number, &type) &&
type == kTableFile) { // Lock file will be deleted at end
Status del = env->DeleteFile(db_path.path + "/" + filenames[i]);
if (result.ok() && !del.ok()) {
result = del;
}
}
}
}
env->GetChildren(archivedir, &archiveFiles);
// Delete archival files.
for (size_t i = 0; i < archiveFiles.size(); ++i) {
if (ParseFileName(archiveFiles[i], &number, &type) &&
type == kLogFile) {
Status del = env->DeleteFile(archivedir + "/" + archiveFiles[i]);
if (result.ok() && !del.ok()) {
result = del;
}
}
}
// ignore case where no archival directory is present.
env->DeleteDir(archivedir);
env->UnlockFile(lock); // Ignore error since state is already gone
env->DeleteFile(lockname);
env->DeleteDir(dbname); // Ignore error in case dir contains other files
env->DeleteDir(soptions.wal_dir);
}
return result;
}
//
// A global method that can dump out the build version
void DumpRocksDBBuildVersion(Logger * log) {
#if !defined(IOS_CROSS_COMPILE)
// if we compile with Xcode, we don't run build_detect_vesion, so we don't
// generate util/build_version.cc
Log(log, "RocksDB version: %d.%d.%d\n", ROCKSDB_MAJOR, ROCKSDB_MINOR,
ROCKSDB_PATCH);
Log(log, "Git sha %s", rocksdb_build_git_sha);
Log(log, "Compile time %s %s",
rocksdb_build_compile_time, rocksdb_build_compile_date);
#endif
}
} // namespace rocksdb