You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
212 lines
7.2 KiB
212 lines
7.2 KiB
// 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.
|
|
|
|
#ifndef STORAGE_LEVELDB_DB_DB_IMPL_H_
|
|
#define STORAGE_LEVELDB_DB_DB_IMPL_H_
|
|
|
|
#include <deque>
|
|
#include <set>
|
|
#include "db/dbformat.h"
|
|
#include "db/log_writer.h"
|
|
#include "db/snapshot.h"
|
|
#include "leveldb/db.h"
|
|
#include "leveldb/env.h"
|
|
#include "port/port.h"
|
|
#include "port/thread_annotations.h"
|
|
|
|
namespace leveldb {
|
|
|
|
class MemTable;
|
|
class TableCache;
|
|
class Version;
|
|
class VersionEdit;
|
|
class VersionSet;
|
|
|
|
class DBImpl : public DB {
|
|
public:
|
|
DBImpl(const Options& options, const std::string& dbname);
|
|
virtual ~DBImpl();
|
|
|
|
// Implementations of the DB interface
|
|
virtual Status Put(const WriteOptions&, const Slice& key, const Slice& value);
|
|
virtual Status Delete(const WriteOptions&, const Slice& key);
|
|
virtual Status Write(const WriteOptions& options, WriteBatch* updates);
|
|
virtual Status Get(const ReadOptions& options,
|
|
const Slice& key,
|
|
std::string* value);
|
|
virtual Iterator* NewIterator(const ReadOptions&);
|
|
virtual const Snapshot* GetSnapshot();
|
|
virtual void ReleaseSnapshot(const Snapshot* snapshot);
|
|
virtual bool GetProperty(const Slice& property, std::string* value);
|
|
virtual void GetApproximateSizes(const Range* range, int n, uint64_t* sizes);
|
|
virtual void CompactRange(const Slice* begin, const Slice* end);
|
|
|
|
// Extra methods (for testing) that are not in the public DB interface
|
|
|
|
// Compact any files in the named level that overlap [*begin,*end]
|
|
void TEST_CompactRange(int level, const Slice* begin, const Slice* end);
|
|
|
|
// Force current memtable contents to be compacted.
|
|
Status TEST_CompactMemTable();
|
|
|
|
// Return an internal iterator over the current state of the database.
|
|
// The keys of this iterator are internal keys (see format.h).
|
|
// The returned iterator should be deleted when no longer needed.
|
|
Iterator* TEST_NewInternalIterator();
|
|
|
|
// Return the maximum overlapping data (in bytes) at next level for any
|
|
// file at a level >= 1.
|
|
int64_t TEST_MaxNextLevelOverlappingBytes();
|
|
|
|
// Record a sample of bytes read at the specified internal key.
|
|
// Samples are taken approximately once every config::kReadBytesPeriod
|
|
// bytes.
|
|
void RecordReadSample(Slice key);
|
|
|
|
private:
|
|
friend class DB;
|
|
struct CompactionState;
|
|
struct Writer;
|
|
|
|
Iterator* NewInternalIterator(const ReadOptions&,
|
|
SequenceNumber* latest_snapshot,
|
|
uint32_t* seed);
|
|
|
|
Status NewDB();
|
|
|
|
// Recover the descriptor from persistent storage. May do a significant
|
|
// amount of work to recover recently logged updates. Any changes to
|
|
// be made to the descriptor are added to *edit.
|
|
Status Recover(VersionEdit* edit, bool* save_manifest)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
void MaybeIgnoreError(Status* s) const;
|
|
|
|
// Delete any unneeded files and stale in-memory entries.
|
|
void DeleteObsoleteFiles();
|
|
|
|
// Compact the in-memory write buffer to disk. Switches to a new
|
|
// log-file/memtable and writes a new descriptor iff successful.
|
|
// Errors are recorded in bg_error_.
|
|
void CompactMemTable() EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
Status RecoverLogFile(uint64_t log_number, bool last_log, bool* save_manifest,
|
|
VersionEdit* edit, SequenceNumber* max_sequence)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
Status WriteLevel0Table(MemTable* mem, VersionEdit* edit, Version* base)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
Status MakeRoomForWrite(bool force /* compact even if there is room? */)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
WriteBatch* BuildBatchGroup(Writer** last_writer);
|
|
|
|
void RecordBackgroundError(const Status& s);
|
|
|
|
void MaybeScheduleCompaction() EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
static void BGWork(void* db);
|
|
void BackgroundCall();
|
|
void BackgroundCompaction() EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
void CleanupCompaction(CompactionState* compact)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
Status DoCompactionWork(CompactionState* compact)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
Status OpenCompactionOutputFile(CompactionState* compact);
|
|
Status FinishCompactionOutputFile(CompactionState* compact, Iterator* input);
|
|
Status InstallCompactionResults(CompactionState* compact)
|
|
EXCLUSIVE_LOCKS_REQUIRED(mutex_);
|
|
|
|
// Constant after construction
|
|
Env* const env_;
|
|
const InternalKeyComparator internal_comparator_;
|
|
const InternalFilterPolicy internal_filter_policy_;
|
|
const Options options_; // options_.comparator == &internal_comparator_
|
|
bool owns_info_log_;
|
|
bool owns_cache_;
|
|
const std::string dbname_;
|
|
|
|
// table_cache_ provides its own synchronization
|
|
TableCache* table_cache_;
|
|
|
|
// Lock over the persistent DB state. Non-NULL iff successfully acquired.
|
|
FileLock* db_lock_;
|
|
|
|
// State below is protected by mutex_
|
|
port::Mutex mutex_;
|
|
port::AtomicPointer shutting_down_;
|
|
port::CondVar bg_cv_; // Signalled when background work finishes
|
|
MemTable* mem_;
|
|
MemTable* imm_; // Memtable being compacted
|
|
port::AtomicPointer has_imm_; // So bg thread can detect non-NULL imm_
|
|
WritableFile* logfile_;
|
|
uint64_t logfile_number_;
|
|
log::Writer* log_;
|
|
uint32_t seed_; // For sampling.
|
|
|
|
// Queue of writers.
|
|
std::deque<Writer*> writers_;
|
|
WriteBatch* tmp_batch_;
|
|
|
|
SnapshotList snapshots_;
|
|
|
|
// Set of table files to protect from deletion because they are
|
|
// part of ongoing compactions.
|
|
std::set<uint64_t> pending_outputs_;
|
|
|
|
// Has a background compaction been scheduled or is running?
|
|
bool bg_compaction_scheduled_;
|
|
|
|
// Information for a manual compaction
|
|
struct ManualCompaction {
|
|
int level;
|
|
bool done;
|
|
const InternalKey* begin; // NULL means beginning of key range
|
|
const InternalKey* end; // NULL means end of key range
|
|
InternalKey tmp_storage; // Used to keep track of compaction progress
|
|
};
|
|
ManualCompaction* manual_compaction_;
|
|
|
|
VersionSet* versions_;
|
|
|
|
// Have we encountered a background error in paranoid mode?
|
|
Status bg_error_;
|
|
|
|
// Per level compaction stats. stats_[level] stores the stats for
|
|
// compactions that produced data for the specified "level".
|
|
struct CompactionStats {
|
|
int64_t micros;
|
|
int64_t bytes_read;
|
|
int64_t bytes_written;
|
|
|
|
CompactionStats() : micros(0), bytes_read(0), bytes_written(0) { }
|
|
|
|
void Add(const CompactionStats& c) {
|
|
this->micros += c.micros;
|
|
this->bytes_read += c.bytes_read;
|
|
this->bytes_written += c.bytes_written;
|
|
}
|
|
};
|
|
CompactionStats stats_[config::kNumLevels];
|
|
|
|
// No copying allowed
|
|
DBImpl(const DBImpl&);
|
|
void operator=(const DBImpl&);
|
|
|
|
const Comparator* user_comparator() const {
|
|
return internal_comparator_.user_comparator();
|
|
}
|
|
};
|
|
|
|
// Sanitize db options. The caller should delete result.info_log if
|
|
// it is not equal to src.info_log.
|
|
extern Options SanitizeOptions(const std::string& db,
|
|
const InternalKeyComparator* icmp,
|
|
const InternalFilterPolicy* ipolicy,
|
|
const Options& src);
|
|
|
|
} // namespace leveldb
|
|
|
|
#endif // STORAGE_LEVELDB_DB_DB_IMPL_H_
|