blob: 4c07ed67c80a2d7bce747e516a080cbf675ab22d [file] [log] [blame]
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#include <map>
#include <queue>
#include <string>
#include <thread>
#include "monitoring/instrumented_mutex.h"
#include "port/port.h"
#include "rocksdb/status.h"
namespace rocksdb {
class Env;
class Logger;
class SstFileManagerImpl;
// DeleteScheduler allows the DB to enforce a rate limit on file deletion,
// Instead of deleteing files immediately, files are moved to trash_dir
// and deleted in a background thread that apply sleep penlty between deletes
// if they are happening in a rate faster than rate_bytes_per_sec,
// Rate limiting can be turned off by setting rate_bytes_per_sec = 0, In this
// case DeleteScheduler will delete files immediately.
class DeleteScheduler {
DeleteScheduler(Env* env, const std::string& trash_dir,
int64_t rate_bytes_per_sec, Logger* info_log,
SstFileManagerImpl* sst_file_manager);
// Return delete rate limit in bytes per second
int64_t GetRateBytesPerSecond() { return rate_bytes_per_sec_.load(); }
// Set delete rate limit in bytes per second
void SetRateBytesPerSecond(int64_t bytes_per_sec) {
// Move file to trash directory and schedule it's deletion
Status DeleteFile(const std::string& fname);
// Wait for all files being deleteing in the background to finish or for
// destructor to be called.
void WaitForEmptyTrash();
// Return a map containing errors that happened in BackgroundEmptyTrash
// file_path => error status
std::map<std::string, Status> GetBackgroundErrors();
uint64_t GetTotalTrashSize() { return total_trash_size_.load(); }
void TEST_SetMaxTrashDBRatio(double r) {
assert(r >= 0);
max_trash_db_ratio_ = r;
Status MoveToTrash(const std::string& file_path, std::string* path_in_trash);
Status DeleteTrashFile(const std::string& path_in_trash,
uint64_t* deleted_bytes);
void BackgroundEmptyTrash();
Env* env_;
// Path to the trash directory
std::string trash_dir_;
// total size of trash directory
std::atomic<uint64_t> total_trash_size_;
// Maximum number of bytes that should be deleted per second
std::atomic<int64_t> rate_bytes_per_sec_;
// Mutex to protect queue_, pending_files_, bg_errors_, closing_
InstrumentedMutex mu_;
// Queue of files in trash that need to be deleted
std::queue<std::string> queue_;
// Number of files in trash that are waiting to be deleted
int32_t pending_files_;
// Errors that happened in BackgroundEmptyTrash (file_path => error)
std::map<std::string, Status> bg_errors_;
// Set to true in ~DeleteScheduler() to force BackgroundEmptyTrash to stop
bool closing_;
// Condition variable signaled in these conditions
// - pending_files_ value change from 0 => 1
// - pending_files_ value change from 1 => 0
// - closing_ value is set to true
InstrumentedCondVar cv_;
// Background thread running BackgroundEmptyTrash
std::unique_ptr<port::Thread> bg_thread_;
// Mutex to protect threads from file name conflicts
InstrumentedMutex file_move_mu_;
Logger* info_log_;
SstFileManagerImpl* sst_file_manager_;
// If the trash size constitutes for more than 25% of the total DB size
// we will start deleting new files passed to DeleteScheduler immediately
double max_trash_db_ratio_ = 0.25;
static const uint64_t kMicrosInSecond = 1000 * 1000LL;
} // namespace rocksdb
#endif // ROCKSDB_LITE