1
0
Fork 0
arangodb/arangod/RocksDBEngine/RocksDBSyncThread.h

80 lines
2.2 KiB
C++

////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2017 ArangoDB GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Jan Steemann
////////////////////////////////////////////////////////////////////////////////
#ifndef ARANGOD_ROCKSDB_ENGINE_SYNC_THREAD_H
#define ARANGOD_ROCKSDB_ENGINE_SYNC_THREAD_H 1
#include "Basics/Common.h"
#include "Basics/ConditionVariable.h"
#include "Basics/Result.h"
#include "Basics/Thread.h"
#include <rocksdb/types.h>
#include <chrono>
namespace rocksdb {
class DB;
}
namespace arangodb {
class RocksDBEngine;
class RocksDBSyncThread final : public Thread {
public:
RocksDBSyncThread(RocksDBEngine* engine, std::chrono::milliseconds interval);
~RocksDBSyncThread();
void beginShutdown() override;
/// @brief updates last sync time and calls the synchronization
/// this is the preferred method to call when trying to avoid redundant
/// syncs by foreground work and the background sync thread
Result syncWal();
/// @brief unconditionally syncs the RocksDB WAL, static variant
static Result sync(rocksdb::DB* db);
protected:
void run() override;
private:
RocksDBEngine* _engine;
/// @brief the sync interval
std::chrono::milliseconds const _interval;
/// @brief last time we synced the RocksDB WAL
std::chrono::time_point<std::chrono::steady_clock> _lastSyncTime;
/// @brief the last definitely synced RocksDB WAL sequence number
rocksdb::SequenceNumber _lastSequenceNumber;
/// @brief protects _lastSyncTime and _lastSequenceNumber
arangodb::basics::ConditionVariable _condition;
};
} // namespace arangodb
#endif