9f7fc3ac45
Summary: ...and fix all the errors :) Jim suggested turning on -Wshadow because it helped him fix number of critical bugs in fbcode. I think it's a good idea to be -Wshadow clean. Test Plan: compiles Reviewers: yhchiang, rven, sdong, ljin Reviewed By: ljin Subscribers: dhruba, leveldb Differential Revision: https://reviews.facebook.net/D27711
1315 lines
46 KiB
C++
1315 lines
46 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 "table/block_based_table_reader.h"
|
|
|
|
#include <string>
|
|
#include <utility>
|
|
|
|
#include "db/dbformat.h"
|
|
|
|
#include "rocksdb/cache.h"
|
|
#include "rocksdb/comparator.h"
|
|
#include "rocksdb/env.h"
|
|
#include "rocksdb/filter_policy.h"
|
|
#include "rocksdb/iterator.h"
|
|
#include "rocksdb/options.h"
|
|
#include "rocksdb/statistics.h"
|
|
#include "rocksdb/table.h"
|
|
#include "rocksdb/table_properties.h"
|
|
|
|
#include "table/block.h"
|
|
#include "table/filter_block.h"
|
|
#include "table/block_based_filter_block.h"
|
|
#include "table/full_filter_block.h"
|
|
#include "table/block_hash_index.h"
|
|
#include "table/block_prefix_index.h"
|
|
#include "table/format.h"
|
|
#include "table/meta_blocks.h"
|
|
#include "table/two_level_iterator.h"
|
|
#include "table/get_context.h"
|
|
|
|
#include "util/coding.h"
|
|
#include "util/perf_context_imp.h"
|
|
#include "util/stop_watch.h"
|
|
|
|
namespace rocksdb {
|
|
|
|
extern const uint64_t kBlockBasedTableMagicNumber;
|
|
extern const std::string kHashIndexPrefixesBlock;
|
|
extern const std::string kHashIndexPrefixesMetadataBlock;
|
|
using std::unique_ptr;
|
|
|
|
typedef BlockBasedTable::IndexReader IndexReader;
|
|
|
|
namespace {
|
|
// The longest the prefix of the cache key used to identify blocks can be.
|
|
// We are using the fact that we know for Posix files the unique ID is three
|
|
// varints.
|
|
// For some reason, compiling for iOS complains that this variable is unused
|
|
const size_t kMaxCacheKeyPrefixSize __attribute__((unused)) =
|
|
kMaxVarint64Length * 3 + 1;
|
|
|
|
// Read the block identified by "handle" from "file".
|
|
// The only relevant option is options.verify_checksums for now.
|
|
// On failure return non-OK.
|
|
// On success fill *result and return OK - caller owns *result
|
|
Status ReadBlockFromFile(RandomAccessFile* file, const Footer& footer,
|
|
const ReadOptions& options, const BlockHandle& handle,
|
|
Block** result, Env* env, bool do_uncompress = true) {
|
|
BlockContents contents;
|
|
Status s = ReadBlockContents(file, footer, options, handle, &contents, env,
|
|
do_uncompress);
|
|
if (s.ok()) {
|
|
*result = new Block(std::move(contents));
|
|
}
|
|
|
|
return s;
|
|
}
|
|
|
|
// Delete the resource that is held by the iterator.
|
|
template <class ResourceType>
|
|
void DeleteHeldResource(void* arg, void* ignored) {
|
|
delete reinterpret_cast<ResourceType*>(arg);
|
|
}
|
|
|
|
// Delete the entry resided in the cache.
|
|
template <class Entry>
|
|
void DeleteCachedEntry(const Slice& key, void* value) {
|
|
auto entry = reinterpret_cast<Entry*>(value);
|
|
delete entry;
|
|
}
|
|
|
|
// Release the cached entry and decrement its ref count.
|
|
void ReleaseCachedEntry(void* arg, void* h) {
|
|
Cache* cache = reinterpret_cast<Cache*>(arg);
|
|
Cache::Handle* handle = reinterpret_cast<Cache::Handle*>(h);
|
|
cache->Release(handle);
|
|
}
|
|
|
|
Slice GetCacheKey(const char* cache_key_prefix, size_t cache_key_prefix_size,
|
|
const BlockHandle& handle, char* cache_key) {
|
|
assert(cache_key != nullptr);
|
|
assert(cache_key_prefix_size != 0);
|
|
assert(cache_key_prefix_size <= kMaxCacheKeyPrefixSize);
|
|
memcpy(cache_key, cache_key_prefix, cache_key_prefix_size);
|
|
char* end =
|
|
EncodeVarint64(cache_key + cache_key_prefix_size, handle.offset());
|
|
return Slice(cache_key, static_cast<size_t>(end - cache_key));
|
|
}
|
|
|
|
Cache::Handle* GetEntryFromCache(Cache* block_cache, const Slice& key,
|
|
Tickers block_cache_miss_ticker,
|
|
Tickers block_cache_hit_ticker,
|
|
Statistics* statistics) {
|
|
auto cache_handle = block_cache->Lookup(key);
|
|
if (cache_handle != nullptr) {
|
|
PERF_COUNTER_ADD(block_cache_hit_count, 1);
|
|
// overall cache hit
|
|
RecordTick(statistics, BLOCK_CACHE_HIT);
|
|
// block-type specific cache hit
|
|
RecordTick(statistics, block_cache_hit_ticker);
|
|
} else {
|
|
// overall cache miss
|
|
RecordTick(statistics, BLOCK_CACHE_MISS);
|
|
// block-type specific cache miss
|
|
RecordTick(statistics, block_cache_miss_ticker);
|
|
}
|
|
|
|
return cache_handle;
|
|
}
|
|
|
|
} // namespace
|
|
|
|
// -- IndexReader and its subclasses
|
|
// IndexReader is the interface that provide the functionality for index access.
|
|
class BlockBasedTable::IndexReader {
|
|
public:
|
|
explicit IndexReader(const Comparator* comparator)
|
|
: comparator_(comparator) {}
|
|
|
|
virtual ~IndexReader() {}
|
|
|
|
// Create an iterator for index access.
|
|
// An iter is passed in, if it is not null, update this one and return it
|
|
// If it is null, create a new Iterator
|
|
virtual Iterator* NewIterator(
|
|
BlockIter* iter = nullptr, bool total_order_seek = true) = 0;
|
|
|
|
// The size of the index.
|
|
virtual size_t size() const = 0;
|
|
|
|
// Report an approximation of how much memory has been used other than memory
|
|
// that was allocated in block cache.
|
|
virtual size_t ApproximateMemoryUsage() const = 0;
|
|
|
|
protected:
|
|
const Comparator* comparator_;
|
|
};
|
|
|
|
// Index that allows binary search lookup for the first key of each block.
|
|
// This class can be viewed as a thin wrapper for `Block` class which already
|
|
// supports binary search.
|
|
class BinarySearchIndexReader : public IndexReader {
|
|
public:
|
|
// Read index from the file and create an intance for
|
|
// `BinarySearchIndexReader`.
|
|
// On success, index_reader will be populated; otherwise it will remain
|
|
// unmodified.
|
|
static Status Create(RandomAccessFile* file, const Footer& footer,
|
|
const BlockHandle& index_handle, Env* env,
|
|
const Comparator* comparator,
|
|
IndexReader** index_reader) {
|
|
Block* index_block = nullptr;
|
|
auto s = ReadBlockFromFile(file, footer, ReadOptions(), index_handle,
|
|
&index_block, env);
|
|
|
|
if (s.ok()) {
|
|
*index_reader = new BinarySearchIndexReader(comparator, index_block);
|
|
}
|
|
|
|
return s;
|
|
}
|
|
|
|
virtual Iterator* NewIterator(
|
|
BlockIter* iter = nullptr, bool dont_care = true) override {
|
|
return index_block_->NewIterator(comparator_, iter, true);
|
|
}
|
|
|
|
virtual size_t size() const override { return index_block_->size(); }
|
|
|
|
virtual size_t ApproximateMemoryUsage() const override {
|
|
assert(index_block_);
|
|
return index_block_->ApproximateMemoryUsage();
|
|
}
|
|
|
|
private:
|
|
BinarySearchIndexReader(const Comparator* comparator, Block* index_block)
|
|
: IndexReader(comparator), index_block_(index_block) {
|
|
assert(index_block_ != nullptr);
|
|
}
|
|
std::unique_ptr<Block> index_block_;
|
|
};
|
|
|
|
// Index that leverages an internal hash table to quicken the lookup for a given
|
|
// key.
|
|
class HashIndexReader : public IndexReader {
|
|
public:
|
|
static Status Create(const SliceTransform* hash_key_extractor,
|
|
const Footer& footer, RandomAccessFile* file, Env* env,
|
|
const Comparator* comparator,
|
|
const BlockHandle& index_handle,
|
|
Iterator* meta_index_iter, IndexReader** index_reader,
|
|
bool hash_index_allow_collision) {
|
|
Block* index_block = nullptr;
|
|
auto s = ReadBlockFromFile(file, footer, ReadOptions(), index_handle,
|
|
&index_block, env);
|
|
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
// Note, failure to create prefix hash index does not need to be a
|
|
// hard error. We can still fall back to the original binary search index.
|
|
// So, Create will succeed regardless, from this point on.
|
|
|
|
auto new_index_reader =
|
|
new HashIndexReader(comparator, index_block);
|
|
*index_reader = new_index_reader;
|
|
|
|
// Get prefixes block
|
|
BlockHandle prefixes_handle;
|
|
s = FindMetaBlock(meta_index_iter, kHashIndexPrefixesBlock,
|
|
&prefixes_handle);
|
|
if (!s.ok()) {
|
|
// TODO: log error
|
|
return Status::OK();
|
|
}
|
|
|
|
// Get index metadata block
|
|
BlockHandle prefixes_meta_handle;
|
|
s = FindMetaBlock(meta_index_iter, kHashIndexPrefixesMetadataBlock,
|
|
&prefixes_meta_handle);
|
|
if (!s.ok()) {
|
|
// TODO: log error
|
|
return Status::OK();
|
|
}
|
|
|
|
// Read contents for the blocks
|
|
BlockContents prefixes_contents;
|
|
s = ReadBlockContents(file, footer, ReadOptions(), prefixes_handle,
|
|
&prefixes_contents, env, true /* do decompression */);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
BlockContents prefixes_meta_contents;
|
|
s = ReadBlockContents(file, footer, ReadOptions(), prefixes_meta_handle,
|
|
&prefixes_meta_contents, env,
|
|
true /* do decompression */);
|
|
if (!s.ok()) {
|
|
// TODO: log error
|
|
return Status::OK();
|
|
}
|
|
|
|
if (!hash_index_allow_collision) {
|
|
// TODO: deprecate once hash_index_allow_collision proves to be stable.
|
|
BlockHashIndex* hash_index = nullptr;
|
|
s = CreateBlockHashIndex(hash_key_extractor,
|
|
prefixes_contents.data,
|
|
prefixes_meta_contents.data,
|
|
&hash_index);
|
|
// TODO: log error
|
|
if (s.ok()) {
|
|
new_index_reader->index_block_->SetBlockHashIndex(hash_index);
|
|
new_index_reader->OwnPrefixesContents(std::move(prefixes_contents));
|
|
}
|
|
} else {
|
|
BlockPrefixIndex* prefix_index = nullptr;
|
|
s = BlockPrefixIndex::Create(hash_key_extractor,
|
|
prefixes_contents.data,
|
|
prefixes_meta_contents.data,
|
|
&prefix_index);
|
|
// TODO: log error
|
|
if (s.ok()) {
|
|
new_index_reader->index_block_->SetBlockPrefixIndex(prefix_index);
|
|
}
|
|
}
|
|
|
|
return Status::OK();
|
|
}
|
|
|
|
virtual Iterator* NewIterator(
|
|
BlockIter* iter = nullptr, bool total_order_seek = true) override {
|
|
return index_block_->NewIterator(comparator_, iter, total_order_seek);
|
|
}
|
|
|
|
virtual size_t size() const override { return index_block_->size(); }
|
|
|
|
virtual size_t ApproximateMemoryUsage() const override {
|
|
assert(index_block_);
|
|
return index_block_->ApproximateMemoryUsage() +
|
|
prefixes_contents_.data.size();
|
|
}
|
|
|
|
private:
|
|
HashIndexReader(const Comparator* comparator, Block* index_block)
|
|
: IndexReader(comparator), index_block_(index_block) {
|
|
assert(index_block_ != nullptr);
|
|
}
|
|
|
|
~HashIndexReader() {
|
|
}
|
|
|
|
void OwnPrefixesContents(BlockContents&& prefixes_contents) {
|
|
prefixes_contents_ = std::move(prefixes_contents);
|
|
}
|
|
|
|
std::unique_ptr<Block> index_block_;
|
|
BlockContents prefixes_contents_;
|
|
};
|
|
|
|
|
|
struct BlockBasedTable::Rep {
|
|
Rep(const ImmutableCFOptions& _ioptions, const EnvOptions& _env_options,
|
|
const BlockBasedTableOptions& _table_opt,
|
|
const InternalKeyComparator& _internal_comparator)
|
|
: ioptions(_ioptions),
|
|
env_options(_env_options),
|
|
table_options(_table_opt),
|
|
filter_policy(_table_opt.filter_policy.get()),
|
|
internal_comparator(_internal_comparator) {}
|
|
|
|
const ImmutableCFOptions& ioptions;
|
|
const EnvOptions& env_options;
|
|
const BlockBasedTableOptions& table_options;
|
|
const FilterPolicy* const filter_policy;
|
|
const InternalKeyComparator& internal_comparator;
|
|
Status status;
|
|
unique_ptr<RandomAccessFile> file;
|
|
char cache_key_prefix[kMaxCacheKeyPrefixSize];
|
|
size_t cache_key_prefix_size = 0;
|
|
char compressed_cache_key_prefix[kMaxCacheKeyPrefixSize];
|
|
size_t compressed_cache_key_prefix_size = 0;
|
|
|
|
// Footer contains the fixed table information
|
|
Footer footer;
|
|
// index_reader and filter will be populated and used only when
|
|
// options.block_cache is nullptr; otherwise we will get the index block via
|
|
// the block cache.
|
|
unique_ptr<IndexReader> index_reader;
|
|
unique_ptr<FilterBlockReader> filter;
|
|
|
|
std::shared_ptr<const TableProperties> table_properties;
|
|
BlockBasedTableOptions::IndexType index_type;
|
|
bool hash_index_allow_collision;
|
|
// TODO(kailiu) It is very ugly to use internal key in table, since table
|
|
// module should not be relying on db module. However to make things easier
|
|
// and compatible with existing code, we introduce a wrapper that allows
|
|
// block to extract prefix without knowing if a key is internal or not.
|
|
unique_ptr<SliceTransform> internal_prefix_transform;
|
|
};
|
|
|
|
BlockBasedTable::~BlockBasedTable() {
|
|
delete rep_;
|
|
}
|
|
|
|
// CachableEntry represents the entries that *may* be fetched from block cache.
|
|
// field `value` is the item we want to get.
|
|
// field `cache_handle` is the cache handle to the block cache. If the value
|
|
// was not read from cache, `cache_handle` will be nullptr.
|
|
template <class TValue>
|
|
struct BlockBasedTable::CachableEntry {
|
|
CachableEntry(TValue* _value, Cache::Handle* _cache_handle)
|
|
: value(_value), cache_handle(_cache_handle) {}
|
|
CachableEntry() : CachableEntry(nullptr, nullptr) {}
|
|
void Release(Cache* cache) {
|
|
if (cache_handle) {
|
|
cache->Release(cache_handle);
|
|
value = nullptr;
|
|
cache_handle = nullptr;
|
|
}
|
|
}
|
|
|
|
TValue* value = nullptr;
|
|
// if the entry is from the cache, cache_handle will be populated.
|
|
Cache::Handle* cache_handle = nullptr;
|
|
};
|
|
|
|
// Helper function to setup the cache key's prefix for the Table.
|
|
void BlockBasedTable::SetupCacheKeyPrefix(Rep* rep) {
|
|
assert(kMaxCacheKeyPrefixSize >= 10);
|
|
rep->cache_key_prefix_size = 0;
|
|
rep->compressed_cache_key_prefix_size = 0;
|
|
if (rep->table_options.block_cache != nullptr) {
|
|
GenerateCachePrefix(rep->table_options.block_cache.get(), rep->file.get(),
|
|
&rep->cache_key_prefix[0],
|
|
&rep->cache_key_prefix_size);
|
|
}
|
|
if (rep->table_options.block_cache_compressed != nullptr) {
|
|
GenerateCachePrefix(rep->table_options.block_cache_compressed.get(),
|
|
rep->file.get(), &rep->compressed_cache_key_prefix[0],
|
|
&rep->compressed_cache_key_prefix_size);
|
|
}
|
|
}
|
|
|
|
void BlockBasedTable::GenerateCachePrefix(Cache* cc,
|
|
RandomAccessFile* file, char* buffer, size_t* size) {
|
|
|
|
// generate an id from the file
|
|
*size = file->GetUniqueId(buffer, kMaxCacheKeyPrefixSize);
|
|
|
|
// If the prefix wasn't generated or was too long,
|
|
// create one from the cache.
|
|
if (*size == 0) {
|
|
char* end = EncodeVarint64(buffer, cc->NewId());
|
|
*size = static_cast<size_t>(end - buffer);
|
|
}
|
|
}
|
|
|
|
void BlockBasedTable::GenerateCachePrefix(Cache* cc,
|
|
WritableFile* file, char* buffer, size_t* size) {
|
|
|
|
// generate an id from the file
|
|
*size = file->GetUniqueId(buffer, kMaxCacheKeyPrefixSize);
|
|
|
|
// If the prefix wasn't generated or was too long,
|
|
// create one from the cache.
|
|
if (*size == 0) {
|
|
char* end = EncodeVarint64(buffer, cc->NewId());
|
|
*size = static_cast<size_t>(end - buffer);
|
|
}
|
|
}
|
|
|
|
Status BlockBasedTable::Open(const ImmutableCFOptions& ioptions,
|
|
const EnvOptions& env_options,
|
|
const BlockBasedTableOptions& table_options,
|
|
const InternalKeyComparator& internal_comparator,
|
|
unique_ptr<RandomAccessFile>&& file,
|
|
uint64_t file_size,
|
|
unique_ptr<TableReader>* table_reader) {
|
|
table_reader->reset();
|
|
|
|
Footer footer(kBlockBasedTableMagicNumber);
|
|
auto s = ReadFooterFromFile(file.get(), file_size, &footer);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
// We've successfully read the footer and the index block: we're
|
|
// ready to serve requests.
|
|
Rep* rep = new BlockBasedTable::Rep(
|
|
ioptions, env_options, table_options, internal_comparator);
|
|
rep->file = std::move(file);
|
|
rep->footer = footer;
|
|
rep->index_type = table_options.index_type;
|
|
rep->hash_index_allow_collision = table_options.hash_index_allow_collision;
|
|
SetupCacheKeyPrefix(rep);
|
|
unique_ptr<BlockBasedTable> new_table(new BlockBasedTable(rep));
|
|
|
|
// Read meta index
|
|
std::unique_ptr<Block> meta;
|
|
std::unique_ptr<Iterator> meta_iter;
|
|
s = ReadMetaBlock(rep, &meta, &meta_iter);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
// Read the properties
|
|
bool found_properties_block = true;
|
|
s = SeekToPropertiesBlock(meta_iter.get(), &found_properties_block);
|
|
|
|
if (!s.ok()) {
|
|
Log(InfoLogLevel::WARN_LEVEL, rep->ioptions.info_log,
|
|
"Cannot seek to properties block from file: %s",
|
|
s.ToString().c_str());
|
|
} else if (found_properties_block) {
|
|
s = meta_iter->status();
|
|
TableProperties* table_properties = nullptr;
|
|
if (s.ok()) {
|
|
s = ReadProperties(meta_iter->value(), rep->file.get(), rep->footer,
|
|
rep->ioptions.env, rep->ioptions.info_log,
|
|
&table_properties);
|
|
}
|
|
|
|
if (!s.ok()) {
|
|
Log(InfoLogLevel::WARN_LEVEL, rep->ioptions.info_log,
|
|
"Encountered error while reading data from properties "
|
|
"block %s", s.ToString().c_str());
|
|
} else {
|
|
rep->table_properties.reset(table_properties);
|
|
}
|
|
} else {
|
|
Log(InfoLogLevel::ERROR_LEVEL, rep->ioptions.info_log,
|
|
"Cannot find Properties block from file.");
|
|
}
|
|
|
|
// Will use block cache for index/filter blocks access?
|
|
if (table_options.cache_index_and_filter_blocks) {
|
|
assert(table_options.block_cache != nullptr);
|
|
// Hack: Call NewIndexIterator() to implicitly add index to the block_cache
|
|
unique_ptr<Iterator> iter(new_table->NewIndexIterator(ReadOptions()));
|
|
s = iter->status();
|
|
|
|
if (s.ok()) {
|
|
// Hack: Call GetFilter() to implicitly add filter to the block_cache
|
|
auto filter_entry = new_table->GetFilter();
|
|
filter_entry.Release(table_options.block_cache.get());
|
|
}
|
|
} else {
|
|
// If we don't use block cache for index/filter blocks access, we'll
|
|
// pre-load these blocks, which will kept in member variables in Rep
|
|
// and with a same life-time as this table object.
|
|
IndexReader* index_reader = nullptr;
|
|
s = new_table->CreateIndexReader(&index_reader, meta_iter.get());
|
|
|
|
if (s.ok()) {
|
|
rep->index_reader.reset(index_reader);
|
|
|
|
// Set filter block
|
|
if (rep->filter_policy) {
|
|
rep->filter.reset(ReadFilter(rep, meta_iter.get(), nullptr));
|
|
}
|
|
} else {
|
|
delete index_reader;
|
|
}
|
|
}
|
|
|
|
if (s.ok()) {
|
|
*table_reader = std::move(new_table);
|
|
}
|
|
|
|
return s;
|
|
}
|
|
|
|
void BlockBasedTable::SetupForCompaction() {
|
|
switch (rep_->ioptions.access_hint_on_compaction_start) {
|
|
case Options::NONE:
|
|
break;
|
|
case Options::NORMAL:
|
|
rep_->file->Hint(RandomAccessFile::NORMAL);
|
|
break;
|
|
case Options::SEQUENTIAL:
|
|
rep_->file->Hint(RandomAccessFile::SEQUENTIAL);
|
|
break;
|
|
case Options::WILLNEED:
|
|
rep_->file->Hint(RandomAccessFile::WILLNEED);
|
|
break;
|
|
default:
|
|
assert(false);
|
|
}
|
|
compaction_optimized_ = true;
|
|
}
|
|
|
|
std::shared_ptr<const TableProperties> BlockBasedTable::GetTableProperties()
|
|
const {
|
|
return rep_->table_properties;
|
|
}
|
|
|
|
size_t BlockBasedTable::ApproximateMemoryUsage() const {
|
|
size_t usage = 0;
|
|
if (rep_->filter) {
|
|
usage += rep_->filter->ApproximateMemoryUsage();
|
|
}
|
|
if (rep_->index_reader) {
|
|
usage += rep_->index_reader->ApproximateMemoryUsage();
|
|
}
|
|
return usage;
|
|
}
|
|
|
|
// Load the meta-block from the file. On success, return the loaded meta block
|
|
// and its iterator.
|
|
Status BlockBasedTable::ReadMetaBlock(
|
|
Rep* rep,
|
|
std::unique_ptr<Block>* meta_block,
|
|
std::unique_ptr<Iterator>* iter) {
|
|
// TODO(sanjay): Skip this if footer.metaindex_handle() size indicates
|
|
// it is an empty block.
|
|
// TODO: we never really verify check sum for meta index block
|
|
Block* meta = nullptr;
|
|
Status s = ReadBlockFromFile(
|
|
rep->file.get(),
|
|
rep->footer,
|
|
ReadOptions(),
|
|
rep->footer.metaindex_handle(),
|
|
&meta,
|
|
rep->ioptions.env);
|
|
|
|
if (!s.ok()) {
|
|
Log(InfoLogLevel::ERROR_LEVEL, rep->ioptions.info_log,
|
|
"Encountered error while reading data from properties"
|
|
" block %s", s.ToString().c_str());
|
|
delete meta;
|
|
return s;
|
|
}
|
|
|
|
meta_block->reset(meta);
|
|
// meta block uses bytewise comparator.
|
|
iter->reset(meta->NewIterator(BytewiseComparator()));
|
|
return Status::OK();
|
|
}
|
|
|
|
Status BlockBasedTable::GetDataBlockFromCache(
|
|
const Slice& block_cache_key, const Slice& compressed_block_cache_key,
|
|
Cache* block_cache, Cache* block_cache_compressed, Statistics* statistics,
|
|
const ReadOptions& read_options,
|
|
BlockBasedTable::CachableEntry<Block>* block) {
|
|
Status s;
|
|
Block* compressed_block = nullptr;
|
|
Cache::Handle* block_cache_compressed_handle = nullptr;
|
|
|
|
// Lookup uncompressed cache first
|
|
if (block_cache != nullptr) {
|
|
block->cache_handle =
|
|
GetEntryFromCache(block_cache, block_cache_key, BLOCK_CACHE_DATA_MISS,
|
|
BLOCK_CACHE_DATA_HIT, statistics);
|
|
if (block->cache_handle != nullptr) {
|
|
block->value =
|
|
reinterpret_cast<Block*>(block_cache->Value(block->cache_handle));
|
|
return s;
|
|
}
|
|
}
|
|
|
|
// If not found, search from the compressed block cache.
|
|
assert(block->cache_handle == nullptr && block->value == nullptr);
|
|
|
|
if (block_cache_compressed == nullptr) {
|
|
return s;
|
|
}
|
|
|
|
assert(!compressed_block_cache_key.empty());
|
|
block_cache_compressed_handle =
|
|
block_cache_compressed->Lookup(compressed_block_cache_key);
|
|
// if we found in the compressed cache, then uncompress and insert into
|
|
// uncompressed cache
|
|
if (block_cache_compressed_handle == nullptr) {
|
|
RecordTick(statistics, BLOCK_CACHE_COMPRESSED_MISS);
|
|
return s;
|
|
}
|
|
|
|
// found compressed block
|
|
RecordTick(statistics, BLOCK_CACHE_COMPRESSED_HIT);
|
|
compressed_block = reinterpret_cast<Block*>(
|
|
block_cache_compressed->Value(block_cache_compressed_handle));
|
|
assert(compressed_block->compression_type() != kNoCompression);
|
|
|
|
// Retrieve the uncompressed contents into a new buffer
|
|
BlockContents contents;
|
|
s = UncompressBlockContents(compressed_block->data(),
|
|
compressed_block->size(), &contents);
|
|
|
|
// Insert uncompressed block into block cache
|
|
if (s.ok()) {
|
|
block->value = new Block(std::move(contents)); // uncompressed block
|
|
assert(block->value->compression_type() == kNoCompression);
|
|
if (block_cache != nullptr && block->value->cachable() &&
|
|
read_options.fill_cache) {
|
|
block->cache_handle =
|
|
block_cache->Insert(block_cache_key, block->value,
|
|
block->value->size(), &DeleteCachedEntry<Block>);
|
|
assert(reinterpret_cast<Block*>(
|
|
block_cache->Value(block->cache_handle)) == block->value);
|
|
}
|
|
}
|
|
|
|
// Release hold on compressed cache entry
|
|
block_cache_compressed->Release(block_cache_compressed_handle);
|
|
return s;
|
|
}
|
|
|
|
Status BlockBasedTable::PutDataBlockToCache(
|
|
const Slice& block_cache_key, const Slice& compressed_block_cache_key,
|
|
Cache* block_cache, Cache* block_cache_compressed,
|
|
const ReadOptions& read_options, Statistics* statistics,
|
|
CachableEntry<Block>* block, Block* raw_block) {
|
|
assert(raw_block->compression_type() == kNoCompression ||
|
|
block_cache_compressed != nullptr);
|
|
|
|
Status s;
|
|
// Retrieve the uncompressed contents into a new buffer
|
|
BlockContents contents;
|
|
if (raw_block->compression_type() != kNoCompression) {
|
|
s = UncompressBlockContents(raw_block->data(), raw_block->size(),
|
|
&contents);
|
|
}
|
|
if (!s.ok()) {
|
|
delete raw_block;
|
|
return s;
|
|
}
|
|
|
|
if (raw_block->compression_type() != kNoCompression) {
|
|
block->value = new Block(std::move(contents)); // uncompressed block
|
|
} else {
|
|
block->value = raw_block;
|
|
raw_block = nullptr;
|
|
}
|
|
|
|
// Insert compressed block into compressed block cache.
|
|
// Release the hold on the compressed cache entry immediately.
|
|
if (block_cache_compressed != nullptr && raw_block != nullptr &&
|
|
raw_block->cachable()) {
|
|
auto cache_handle = block_cache_compressed->Insert(
|
|
compressed_block_cache_key, raw_block, raw_block->size(),
|
|
&DeleteCachedEntry<Block>);
|
|
block_cache_compressed->Release(cache_handle);
|
|
RecordTick(statistics, BLOCK_CACHE_COMPRESSED_MISS);
|
|
// Avoid the following code to delete this cached block.
|
|
raw_block = nullptr;
|
|
}
|
|
delete raw_block;
|
|
|
|
// insert into uncompressed block cache
|
|
assert((block->value->compression_type() == kNoCompression));
|
|
if (block_cache != nullptr && block->value->cachable()) {
|
|
block->cache_handle =
|
|
block_cache->Insert(block_cache_key, block->value, block->value->size(),
|
|
&DeleteCachedEntry<Block>);
|
|
RecordTick(statistics, BLOCK_CACHE_ADD);
|
|
assert(reinterpret_cast<Block*>(block_cache->Value(block->cache_handle)) ==
|
|
block->value);
|
|
}
|
|
|
|
return s;
|
|
}
|
|
|
|
FilterBlockReader* BlockBasedTable::ReadFilter(
|
|
Rep* rep, Iterator* meta_index_iter, size_t* filter_size) {
|
|
// TODO: We might want to unify with ReadBlockFromFile() if we start
|
|
// requiring checksum verification in Table::Open.
|
|
for (auto prefix : {kFullFilterBlockPrefix, kFilterBlockPrefix}) {
|
|
std::string filter_block_key = prefix;
|
|
filter_block_key.append(rep->filter_policy->Name());
|
|
BlockHandle handle;
|
|
if (FindMetaBlock(meta_index_iter, filter_block_key, &handle).ok()) {
|
|
BlockContents block;
|
|
if (!ReadBlockContents(rep->file.get(), rep->footer, ReadOptions(),
|
|
handle, &block, rep->ioptions.env, false).ok()) {
|
|
// Error reading the block
|
|
return nullptr;
|
|
}
|
|
|
|
if (filter_size) {
|
|
*filter_size = block.data.size();
|
|
}
|
|
|
|
assert(rep->filter_policy);
|
|
if (kFilterBlockPrefix == prefix) {
|
|
return new BlockBasedFilterBlockReader(
|
|
rep->ioptions.prefix_extractor, rep->table_options,
|
|
std::move(block));
|
|
} else if (kFullFilterBlockPrefix == prefix) {
|
|
auto filter_bits_reader = rep->filter_policy->
|
|
GetFilterBitsReader(block.data);
|
|
if (filter_bits_reader != nullptr) {
|
|
return new FullFilterBlockReader(rep->ioptions.prefix_extractor,
|
|
rep->table_options,
|
|
std::move(block),
|
|
filter_bits_reader);
|
|
}
|
|
} else {
|
|
assert(false);
|
|
return nullptr;
|
|
}
|
|
}
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
BlockBasedTable::CachableEntry<FilterBlockReader> BlockBasedTable::GetFilter(
|
|
bool no_io) const {
|
|
// If cache_index_and_filter_blocks is false, filter should be pre-populated.
|
|
// We will return rep_->filter anyway. rep_->filter can be nullptr if filter
|
|
// read fails at Open() time. We don't want to reload again since it will
|
|
// most probably fail again.
|
|
if (!rep_->table_options.cache_index_and_filter_blocks) {
|
|
return {rep_->filter.get(), nullptr /* cache handle */};
|
|
}
|
|
|
|
Cache* block_cache = rep_->table_options.block_cache.get();
|
|
if (rep_->filter_policy == nullptr /* do not use filter */ ||
|
|
block_cache == nullptr /* no block cache at all */) {
|
|
return {nullptr /* filter */, nullptr /* cache handle */};
|
|
}
|
|
|
|
// Fetching from the cache
|
|
char cache_key[kMaxCacheKeyPrefixSize + kMaxVarint64Length];
|
|
auto key = GetCacheKey(rep_->cache_key_prefix, rep_->cache_key_prefix_size,
|
|
rep_->footer.metaindex_handle(),
|
|
cache_key);
|
|
|
|
Statistics* statistics = rep_->ioptions.statistics;
|
|
auto cache_handle =
|
|
GetEntryFromCache(block_cache, key, BLOCK_CACHE_FILTER_MISS,
|
|
BLOCK_CACHE_FILTER_HIT, statistics);
|
|
|
|
FilterBlockReader* filter = nullptr;
|
|
if (cache_handle != nullptr) {
|
|
filter = reinterpret_cast<FilterBlockReader*>(
|
|
block_cache->Value(cache_handle));
|
|
} else if (no_io) {
|
|
// Do not invoke any io.
|
|
return CachableEntry<FilterBlockReader>();
|
|
} else {
|
|
size_t filter_size = 0;
|
|
std::unique_ptr<Block> meta;
|
|
std::unique_ptr<Iterator> iter;
|
|
auto s = ReadMetaBlock(rep_, &meta, &iter);
|
|
|
|
if (s.ok()) {
|
|
filter = ReadFilter(rep_, iter.get(), &filter_size);
|
|
if (filter != nullptr) {
|
|
assert(filter_size > 0);
|
|
cache_handle = block_cache->Insert(
|
|
key, filter, filter_size, &DeleteCachedEntry<FilterBlockReader>);
|
|
RecordTick(statistics, BLOCK_CACHE_ADD);
|
|
}
|
|
}
|
|
}
|
|
|
|
return { filter, cache_handle };
|
|
}
|
|
|
|
Iterator* BlockBasedTable::NewIndexIterator(const ReadOptions& read_options,
|
|
BlockIter* input_iter) {
|
|
// index reader has already been pre-populated.
|
|
if (rep_->index_reader) {
|
|
return rep_->index_reader->NewIterator(
|
|
input_iter, read_options.total_order_seek);
|
|
}
|
|
|
|
bool no_io = read_options.read_tier == kBlockCacheTier;
|
|
Cache* block_cache = rep_->table_options.block_cache.get();
|
|
char cache_key[kMaxCacheKeyPrefixSize + kMaxVarint64Length];
|
|
auto key = GetCacheKey(rep_->cache_key_prefix, rep_->cache_key_prefix_size,
|
|
rep_->footer.index_handle(), cache_key);
|
|
Statistics* statistics = rep_->ioptions.statistics;
|
|
auto cache_handle =
|
|
GetEntryFromCache(block_cache, key, BLOCK_CACHE_INDEX_MISS,
|
|
BLOCK_CACHE_INDEX_HIT, statistics);
|
|
|
|
if (cache_handle == nullptr && no_io) {
|
|
if (input_iter != nullptr) {
|
|
input_iter->SetStatus(Status::Incomplete("no blocking io"));
|
|
return input_iter;
|
|
} else {
|
|
return NewErrorIterator(Status::Incomplete("no blocking io"));
|
|
}
|
|
}
|
|
|
|
IndexReader* index_reader = nullptr;
|
|
if (cache_handle != nullptr) {
|
|
index_reader =
|
|
reinterpret_cast<IndexReader*>(block_cache->Value(cache_handle));
|
|
} else {
|
|
// Create index reader and put it in the cache.
|
|
Status s;
|
|
s = CreateIndexReader(&index_reader);
|
|
|
|
if (!s.ok()) {
|
|
// make sure if something goes wrong, index_reader shall remain intact.
|
|
assert(index_reader == nullptr);
|
|
if (input_iter != nullptr) {
|
|
input_iter->SetStatus(s);
|
|
return input_iter;
|
|
} else {
|
|
return NewErrorIterator(s);
|
|
}
|
|
}
|
|
|
|
cache_handle = block_cache->Insert(key, index_reader, index_reader->size(),
|
|
&DeleteCachedEntry<IndexReader>);
|
|
RecordTick(statistics, BLOCK_CACHE_ADD);
|
|
}
|
|
|
|
assert(cache_handle);
|
|
auto* iter = index_reader->NewIterator(
|
|
input_iter, read_options.total_order_seek);
|
|
iter->RegisterCleanup(&ReleaseCachedEntry, block_cache, cache_handle);
|
|
return iter;
|
|
}
|
|
|
|
// Convert an index iterator value (i.e., an encoded BlockHandle)
|
|
// into an iterator over the contents of the corresponding block.
|
|
// If input_iter is null, new a iterator
|
|
// If input_iter is not null, update this iter and return it
|
|
Iterator* BlockBasedTable::NewDataBlockIterator(Rep* rep,
|
|
const ReadOptions& ro, const Slice& index_value,
|
|
BlockIter* input_iter) {
|
|
const bool no_io = (ro.read_tier == kBlockCacheTier);
|
|
Cache* block_cache = rep->table_options.block_cache.get();
|
|
Cache* block_cache_compressed =
|
|
rep->table_options.block_cache_compressed.get();
|
|
CachableEntry<Block> block;
|
|
|
|
BlockHandle handle;
|
|
Slice input = index_value;
|
|
// We intentionally allow extra stuff in index_value so that we
|
|
// can add more features in the future.
|
|
Status s = handle.DecodeFrom(&input);
|
|
|
|
if (!s.ok()) {
|
|
if (input_iter != nullptr) {
|
|
input_iter->SetStatus(s);
|
|
return input_iter;
|
|
} else {
|
|
return NewErrorIterator(s);
|
|
}
|
|
}
|
|
|
|
// If either block cache is enabled, we'll try to read from it.
|
|
if (block_cache != nullptr || block_cache_compressed != nullptr) {
|
|
Statistics* statistics = rep->ioptions.statistics;
|
|
char cache_key[kMaxCacheKeyPrefixSize + kMaxVarint64Length];
|
|
char compressed_cache_key[kMaxCacheKeyPrefixSize + kMaxVarint64Length];
|
|
Slice key, /* key to the block cache */
|
|
ckey /* key to the compressed block cache */;
|
|
|
|
// create key for block cache
|
|
if (block_cache != nullptr) {
|
|
key = GetCacheKey(rep->cache_key_prefix, rep->cache_key_prefix_size,
|
|
handle, cache_key);
|
|
}
|
|
|
|
if (block_cache_compressed != nullptr) {
|
|
ckey = GetCacheKey(rep->compressed_cache_key_prefix,
|
|
rep->compressed_cache_key_prefix_size, handle,
|
|
compressed_cache_key);
|
|
}
|
|
|
|
s = GetDataBlockFromCache(key, ckey, block_cache, block_cache_compressed,
|
|
statistics, ro, &block);
|
|
|
|
if (block.value == nullptr && !no_io && ro.fill_cache) {
|
|
Block* raw_block = nullptr;
|
|
{
|
|
StopWatch sw(rep->ioptions.env, statistics, READ_BLOCK_GET_MICROS);
|
|
s = ReadBlockFromFile(rep->file.get(), rep->footer, ro, handle,
|
|
&raw_block, rep->ioptions.env,
|
|
block_cache_compressed == nullptr);
|
|
}
|
|
|
|
if (s.ok()) {
|
|
s = PutDataBlockToCache(key, ckey, block_cache, block_cache_compressed,
|
|
ro, statistics, &block, raw_block);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Didn't get any data from block caches.
|
|
if (block.value == nullptr) {
|
|
if (no_io) {
|
|
// Could not read from block_cache and can't do IO
|
|
if (input_iter != nullptr) {
|
|
input_iter->SetStatus(Status::Incomplete("no blocking io"));
|
|
return input_iter;
|
|
} else {
|
|
return NewErrorIterator(Status::Incomplete("no blocking io"));
|
|
}
|
|
}
|
|
s = ReadBlockFromFile(rep->file.get(), rep->footer, ro, handle,
|
|
&block.value, rep->ioptions.env);
|
|
}
|
|
|
|
Iterator* iter;
|
|
if (block.value != nullptr) {
|
|
iter = block.value->NewIterator(&rep->internal_comparator, input_iter);
|
|
if (block.cache_handle != nullptr) {
|
|
iter->RegisterCleanup(&ReleaseCachedEntry, block_cache,
|
|
block.cache_handle);
|
|
} else {
|
|
iter->RegisterCleanup(&DeleteHeldResource<Block>, block.value, nullptr);
|
|
}
|
|
} else {
|
|
if (input_iter != nullptr) {
|
|
input_iter->SetStatus(s);
|
|
iter = input_iter;
|
|
} else {
|
|
iter = NewErrorIterator(s);
|
|
}
|
|
}
|
|
return iter;
|
|
}
|
|
|
|
class BlockBasedTable::BlockEntryIteratorState : public TwoLevelIteratorState {
|
|
public:
|
|
BlockEntryIteratorState(BlockBasedTable* table,
|
|
const ReadOptions& read_options)
|
|
: TwoLevelIteratorState(
|
|
table->rep_->ioptions.prefix_extractor != nullptr),
|
|
table_(table),
|
|
read_options_(read_options) {}
|
|
|
|
Iterator* NewSecondaryIterator(const Slice& index_value) override {
|
|
return NewDataBlockIterator(table_->rep_, read_options_, index_value);
|
|
}
|
|
|
|
bool PrefixMayMatch(const Slice& internal_key) override {
|
|
if (read_options_.total_order_seek) {
|
|
return true;
|
|
}
|
|
return table_->PrefixMayMatch(internal_key);
|
|
}
|
|
|
|
private:
|
|
// Don't own table_
|
|
BlockBasedTable* table_;
|
|
const ReadOptions read_options_;
|
|
};
|
|
|
|
// This will be broken if the user specifies an unusual implementation
|
|
// of Options.comparator, or if the user specifies an unusual
|
|
// definition of prefixes in BlockBasedTableOptions.filter_policy.
|
|
// In particular, we require the following three properties:
|
|
//
|
|
// 1) key.starts_with(prefix(key))
|
|
// 2) Compare(prefix(key), key) <= 0.
|
|
// 3) If Compare(key1, key2) <= 0, then Compare(prefix(key1), prefix(key2)) <= 0
|
|
//
|
|
// Otherwise, this method guarantees no I/O will be incurred.
|
|
//
|
|
// REQUIRES: this method shouldn't be called while the DB lock is held.
|
|
bool BlockBasedTable::PrefixMayMatch(const Slice& internal_key) {
|
|
if (!rep_->filter_policy) {
|
|
return true;
|
|
}
|
|
|
|
assert(rep_->ioptions.prefix_extractor != nullptr);
|
|
auto prefix = rep_->ioptions.prefix_extractor->Transform(
|
|
ExtractUserKey(internal_key));
|
|
InternalKey internal_key_prefix(prefix, 0, kTypeValue);
|
|
auto internal_prefix = internal_key_prefix.Encode();
|
|
|
|
bool may_match = true;
|
|
Status s;
|
|
|
|
// To prevent any io operation in this method, we set `read_tier` to make
|
|
// sure we always read index or filter only when they have already been
|
|
// loaded to memory.
|
|
ReadOptions no_io_read_options;
|
|
no_io_read_options.read_tier = kBlockCacheTier;
|
|
|
|
// First, try check with full filter
|
|
auto filter_entry = GetFilter(true /* no io */);
|
|
FilterBlockReader* filter = filter_entry.value;
|
|
if (filter != nullptr && !filter->IsBlockBased()) {
|
|
may_match = filter->PrefixMayMatch(prefix);
|
|
}
|
|
|
|
// Then, try find it within each block
|
|
if (may_match) {
|
|
unique_ptr<Iterator> iiter(NewIndexIterator(no_io_read_options));
|
|
iiter->Seek(internal_prefix);
|
|
|
|
if (!iiter->Valid()) {
|
|
// we're past end of file
|
|
// if it's incomplete, it means that we avoided I/O
|
|
// and we're not really sure that we're past the end
|
|
// of the file
|
|
may_match = iiter->status().IsIncomplete();
|
|
} else if (ExtractUserKey(iiter->key()).starts_with(
|
|
ExtractUserKey(internal_prefix))) {
|
|
// we need to check for this subtle case because our only
|
|
// guarantee is that "the key is a string >= last key in that data
|
|
// block" according to the doc/table_format.txt spec.
|
|
//
|
|
// Suppose iiter->key() starts with the desired prefix; it is not
|
|
// necessarily the case that the corresponding data block will
|
|
// contain the prefix, since iiter->key() need not be in the
|
|
// block. However, the next data block may contain the prefix, so
|
|
// we return true to play it safe.
|
|
may_match = true;
|
|
} else if (filter != nullptr && filter->IsBlockBased()) {
|
|
// iiter->key() does NOT start with the desired prefix. Because
|
|
// Seek() finds the first key that is >= the seek target, this
|
|
// means that iiter->key() > prefix. Thus, any data blocks coming
|
|
// after the data block corresponding to iiter->key() cannot
|
|
// possibly contain the key. Thus, the corresponding data block
|
|
// is the only on could potentially contain the prefix.
|
|
Slice handle_value = iiter->value();
|
|
BlockHandle handle;
|
|
s = handle.DecodeFrom(&handle_value);
|
|
assert(s.ok());
|
|
may_match = filter->PrefixMayMatch(prefix, handle.offset());
|
|
}
|
|
}
|
|
|
|
Statistics* statistics = rep_->ioptions.statistics;
|
|
RecordTick(statistics, BLOOM_FILTER_PREFIX_CHECKED);
|
|
if (!may_match) {
|
|
RecordTick(statistics, BLOOM_FILTER_PREFIX_USEFUL);
|
|
}
|
|
|
|
filter_entry.Release(rep_->table_options.block_cache.get());
|
|
return may_match;
|
|
}
|
|
|
|
Iterator* BlockBasedTable::NewIterator(const ReadOptions& read_options,
|
|
Arena* arena) {
|
|
return NewTwoLevelIterator(new BlockEntryIteratorState(this, read_options),
|
|
NewIndexIterator(read_options), arena);
|
|
}
|
|
|
|
Status BlockBasedTable::Get(
|
|
const ReadOptions& read_options, const Slice& key,
|
|
GetContext* get_context) {
|
|
Status s;
|
|
auto filter_entry = GetFilter(read_options.read_tier == kBlockCacheTier);
|
|
FilterBlockReader* filter = filter_entry.value;
|
|
|
|
// First check the full filter
|
|
// If full filter not useful, Then go into each block
|
|
if (filter != nullptr && !filter->IsBlockBased()
|
|
&& !filter->KeyMayMatch(ExtractUserKey(key))) {
|
|
RecordTick(rep_->ioptions.statistics, BLOOM_FILTER_USEFUL);
|
|
} else {
|
|
BlockIter iiter;
|
|
NewIndexIterator(read_options, &iiter);
|
|
|
|
bool done = false;
|
|
for (iiter.Seek(key); iiter.Valid() && !done; iiter.Next()) {
|
|
Slice handle_value = iiter.value();
|
|
|
|
BlockHandle handle;
|
|
bool not_exist_in_filter =
|
|
filter != nullptr && filter->IsBlockBased() == true &&
|
|
handle.DecodeFrom(&handle_value).ok() &&
|
|
!filter->KeyMayMatch(ExtractUserKey(key), handle.offset());
|
|
|
|
if (not_exist_in_filter) {
|
|
// Not found
|
|
// TODO: think about interaction with Merge. If a user key cannot
|
|
// cross one data block, we should be fine.
|
|
RecordTick(rep_->ioptions.statistics, BLOOM_FILTER_USEFUL);
|
|
break;
|
|
} else {
|
|
BlockIter biter;
|
|
NewDataBlockIterator(rep_, read_options, iiter.value(), &biter);
|
|
|
|
if (read_options.read_tier && biter.status().IsIncomplete()) {
|
|
// couldn't get block from block_cache
|
|
// Update Saver.state to Found because we are only looking for whether
|
|
// we can guarantee the key is not there when "no_io" is set
|
|
get_context->MarkKeyMayExist();
|
|
break;
|
|
}
|
|
if (!biter.status().ok()) {
|
|
s = biter.status();
|
|
break;
|
|
}
|
|
|
|
// Call the *saver function on each entry/block until it returns false
|
|
for (biter.Seek(key); biter.Valid(); biter.Next()) {
|
|
ParsedInternalKey parsed_key;
|
|
if (!ParseInternalKey(biter.key(), &parsed_key)) {
|
|
s = Status::Corruption(Slice());
|
|
}
|
|
|
|
if (!get_context->SaveValue(parsed_key, biter.value())) {
|
|
done = true;
|
|
break;
|
|
}
|
|
}
|
|
s = biter.status();
|
|
}
|
|
}
|
|
if (s.ok()) {
|
|
s = iiter.status();
|
|
}
|
|
}
|
|
|
|
filter_entry.Release(rep_->table_options.block_cache.get());
|
|
return s;
|
|
}
|
|
|
|
bool BlockBasedTable::TEST_KeyInCache(const ReadOptions& options,
|
|
const Slice& key) {
|
|
std::unique_ptr<Iterator> iiter(NewIndexIterator(options));
|
|
iiter->Seek(key);
|
|
assert(iiter->Valid());
|
|
CachableEntry<Block> block;
|
|
|
|
BlockHandle handle;
|
|
Slice input = iiter->value();
|
|
Status s = handle.DecodeFrom(&input);
|
|
assert(s.ok());
|
|
Cache* block_cache = rep_->table_options.block_cache.get();
|
|
assert(block_cache != nullptr);
|
|
|
|
char cache_key_storage[kMaxCacheKeyPrefixSize + kMaxVarint64Length];
|
|
Slice cache_key =
|
|
GetCacheKey(rep_->cache_key_prefix, rep_->cache_key_prefix_size,
|
|
handle, cache_key_storage);
|
|
Slice ckey;
|
|
|
|
s = GetDataBlockFromCache(cache_key, ckey, block_cache, nullptr, nullptr,
|
|
options, &block);
|
|
assert(s.ok());
|
|
bool in_cache = block.value != nullptr;
|
|
if (in_cache) {
|
|
ReleaseCachedEntry(block_cache, block.cache_handle);
|
|
}
|
|
return in_cache;
|
|
}
|
|
|
|
// REQUIRES: The following fields of rep_ should have already been populated:
|
|
// 1. file
|
|
// 2. index_handle,
|
|
// 3. options
|
|
// 4. internal_comparator
|
|
// 5. index_type
|
|
Status BlockBasedTable::CreateIndexReader(IndexReader** index_reader,
|
|
Iterator* preloaded_meta_index_iter) {
|
|
// Some old version of block-based tables don't have index type present in
|
|
// table properties. If that's the case we can safely use the kBinarySearch.
|
|
auto index_type_on_file = BlockBasedTableOptions::kBinarySearch;
|
|
if (rep_->table_properties) {
|
|
auto& props = rep_->table_properties->user_collected_properties;
|
|
auto pos = props.find(BlockBasedTablePropertyNames::kIndexType);
|
|
if (pos != props.end()) {
|
|
index_type_on_file = static_cast<BlockBasedTableOptions::IndexType>(
|
|
DecodeFixed32(pos->second.c_str()));
|
|
}
|
|
}
|
|
|
|
auto file = rep_->file.get();
|
|
auto env = rep_->ioptions.env;
|
|
auto comparator = &rep_->internal_comparator;
|
|
const Footer& footer = rep_->footer;
|
|
|
|
if (index_type_on_file == BlockBasedTableOptions::kHashSearch &&
|
|
rep_->ioptions.prefix_extractor == nullptr) {
|
|
Log(InfoLogLevel::WARN_LEVEL, rep_->ioptions.info_log,
|
|
"BlockBasedTableOptions::kHashSearch requires "
|
|
"options.prefix_extractor to be set."
|
|
" Fall back to binary seach index.");
|
|
index_type_on_file = BlockBasedTableOptions::kBinarySearch;
|
|
}
|
|
|
|
switch (index_type_on_file) {
|
|
case BlockBasedTableOptions::kBinarySearch: {
|
|
return BinarySearchIndexReader::Create(
|
|
file, footer, footer.index_handle(), env, comparator, index_reader);
|
|
}
|
|
case BlockBasedTableOptions::kHashSearch: {
|
|
std::unique_ptr<Block> meta_guard;
|
|
std::unique_ptr<Iterator> meta_iter_guard;
|
|
auto meta_index_iter = preloaded_meta_index_iter;
|
|
if (meta_index_iter == nullptr) {
|
|
auto s = ReadMetaBlock(rep_, &meta_guard, &meta_iter_guard);
|
|
if (!s.ok()) {
|
|
// we simply fall back to binary search in case there is any
|
|
// problem with prefix hash index loading.
|
|
Log(InfoLogLevel::WARN_LEVEL, rep_->ioptions.info_log,
|
|
"Unable to read the metaindex block."
|
|
" Fall back to binary seach index.");
|
|
return BinarySearchIndexReader::Create(
|
|
file, footer, footer.index_handle(), env, comparator, index_reader);
|
|
}
|
|
meta_index_iter = meta_iter_guard.get();
|
|
}
|
|
|
|
// We need to wrap data with internal_prefix_transform to make sure it can
|
|
// handle prefix correctly.
|
|
rep_->internal_prefix_transform.reset(
|
|
new InternalKeySliceTransform(rep_->ioptions.prefix_extractor));
|
|
return HashIndexReader::Create(
|
|
rep_->internal_prefix_transform.get(), footer, file, env, comparator,
|
|
footer.index_handle(), meta_index_iter, index_reader,
|
|
rep_->hash_index_allow_collision);
|
|
}
|
|
default: {
|
|
std::string error_message =
|
|
"Unrecognized index type: " + std::to_string(rep_->index_type);
|
|
return Status::InvalidArgument(error_message.c_str());
|
|
}
|
|
}
|
|
}
|
|
|
|
uint64_t BlockBasedTable::ApproximateOffsetOf(const Slice& key) {
|
|
unique_ptr<Iterator> index_iter(NewIndexIterator(ReadOptions()));
|
|
|
|
index_iter->Seek(key);
|
|
uint64_t result;
|
|
if (index_iter->Valid()) {
|
|
BlockHandle handle;
|
|
Slice input = index_iter->value();
|
|
Status s = handle.DecodeFrom(&input);
|
|
if (s.ok()) {
|
|
result = handle.offset();
|
|
} else {
|
|
// Strange: we can't decode the block handle in the index block.
|
|
// We'll just return the offset of the metaindex block, which is
|
|
// close to the whole file size for this case.
|
|
result = rep_->footer.metaindex_handle().offset();
|
|
}
|
|
} else {
|
|
// key is past the last key in the file. If table_properties is not
|
|
// available, approximate the offset by returning the offset of the
|
|
// metaindex block (which is right near the end of the file).
|
|
result = 0;
|
|
if (rep_->table_properties) {
|
|
result = rep_->table_properties->data_size;
|
|
}
|
|
// table_properties is not present in the table.
|
|
if (result == 0) {
|
|
result = rep_->footer.metaindex_handle().offset();
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
bool BlockBasedTable::TEST_filter_block_preloaded() const {
|
|
return rep_->filter != nullptr;
|
|
}
|
|
|
|
bool BlockBasedTable::TEST_index_reader_preloaded() const {
|
|
return rep_->index_reader != nullptr;
|
|
}
|
|
|
|
} // namespace rocksdb
|