rocksdb/db/flush_job.h
Igor Canadi 4ab26c5ad1 Smarter purging during flush
Summary:
Currently, we only purge duplicate keys and deletions during flush if `earliest_seqno_in_memtable <= newest_snapshot`. This means that the newest snapshot happened before we first created the memtable. This is almost never true for MyRocks and MongoRocks.

This patch makes purging during flush able to understand snapshots. The main logic is copied from compaction_job.cc, although the logic over there is much more complicated and extensive. However, we should try to merge the common functionality at some point.

I need this patch to implement no_overwrite_i_promise functionality for flush. We'll also need this to support SingleDelete() during Flush(). @yoshinorim requested the feature.

Test Plan:
make check
I had to adjust some unit tests to understand this new behavior

Reviewers: yhchiang, yoshinorim, anthony, sdong, noetzli

Reviewed By: noetzli

Subscribers: yoshinorim, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42087
2015-08-24 11:11:12 -07:00

95 lines
3.0 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.
#pragma once
#include <atomic>
#include <deque>
#include <limits>
#include <set>
#include <utility>
#include <vector>
#include <string>
#include "db/dbformat.h"
#include "db/column_family.h"
#include "db/log_writer.h"
#include "db/memtable_list.h"
#include "db/snapshot_impl.h"
#include "db/version_edit.h"
#include "port/port.h"
#include "rocksdb/db.h"
#include "rocksdb/env.h"
#include "rocksdb/memtablerep.h"
#include "rocksdb/transaction_log.h"
#include "util/autovector.h"
#include "util/event_logger.h"
#include "util/instrumented_mutex.h"
#include "util/stop_watch.h"
#include "util/thread_local.h"
#include "util/scoped_arena_iterator.h"
#include "db/internal_stats.h"
#include "db/write_controller.h"
#include "db/flush_scheduler.h"
#include "db/write_thread.h"
#include "db/job_context.h"
namespace rocksdb {
class MemTable;
class TableCache;
class Version;
class VersionEdit;
class VersionSet;
class Arena;
class FlushJob {
public:
// TODO(icanadi) make effort to reduce number of parameters here
// IMPORTANT: mutable_cf_options needs to be alive while FlushJob is alive
FlushJob(const std::string& dbname, ColumnFamilyData* cfd,
const DBOptions& db_options,
const MutableCFOptions& mutable_cf_options,
const EnvOptions& env_options, VersionSet* versions,
InstrumentedMutex* db_mutex, std::atomic<bool>* shutting_down,
std::vector<SequenceNumber> existing_snapshots,
JobContext* job_context, LogBuffer* log_buffer,
Directory* db_directory, Directory* output_file_directory,
CompressionType output_compression, Statistics* stats,
EventLogger* event_logger);
~FlushJob();
Status Run(FileMetaData* file_meta = nullptr);
private:
void ReportStartedFlush();
void ReportFlushInputSize(const autovector<MemTable*>& mems);
void RecordFlushIOStats();
Status WriteLevel0Table(const autovector<MemTable*>& mems, VersionEdit* edit,
FileMetaData* meta);
const std::string& dbname_;
ColumnFamilyData* cfd_;
const DBOptions& db_options_;
const MutableCFOptions& mutable_cf_options_;
const EnvOptions& env_options_;
VersionSet* versions_;
InstrumentedMutex* db_mutex_;
std::atomic<bool>* shutting_down_;
std::vector<SequenceNumber> existing_snapshots_;
JobContext* job_context_;
LogBuffer* log_buffer_;
Directory* db_directory_;
Directory* output_file_directory_;
CompressionType output_compression_;
Statistics* stats_;
EventLogger* event_logger_;
};
} // namespace rocksdb