d6c838f1e1
Summary: Add a new class SstFileTracker that will be notified whenever a DB add/delete/move and sst file, it will also replace DeleteScheduler SstFileTracker can be used later to abort writes when we exceed a specific size Test Plan: unit tests Reviewers: rven, anthony, yhchiang, sdong Reviewed By: sdong Subscribers: igor, lovro, march, dhruba Differential Revision: https://reviews.facebook.net/D50469
90 lines
3.0 KiB
C++
90 lines
3.0 KiB
C++
// Copyright (c) 2015, 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.
|
|
|
|
#pragma once
|
|
|
|
#include <map>
|
|
#include <queue>
|
|
#include <string>
|
|
#include <thread>
|
|
|
|
#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 {
|
|
public:
|
|
DeleteScheduler(Env* env, const std::string& trash_dir,
|
|
int64_t rate_bytes_per_sec, Logger* info_log,
|
|
SstFileManagerImpl* sst_file_manager);
|
|
|
|
~DeleteScheduler();
|
|
|
|
// Return delete rate limit in bytes per second
|
|
int64_t GetRateBytesPerSecond() { return rate_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();
|
|
|
|
private:
|
|
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_;
|
|
// Maximum number of bytes that should be deleted per second
|
|
int64_t rate_bytes_per_sec_;
|
|
// Mutex to protect queue_, pending_files_, bg_errors_, closing_
|
|
port::Mutex 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
|
|
port::CondVar cv_;
|
|
// Background thread running BackgroundEmptyTrash
|
|
std::unique_ptr<std::thread> bg_thread_;
|
|
// Mutex to protect threads from file name conflicts
|
|
port::Mutex file_move_mu_;
|
|
Logger* info_log_;
|
|
SstFileManagerImpl* sst_file_manager_;
|
|
static const uint64_t kMicrosInSecond = 1000 * 1000LL;
|
|
};
|
|
|
|
} // namespace rocksdb
|