/usr/include/rocksdb/delete_scheduler.h is in librocksdb-dev 4.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 | // 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 <string>
#include "rocksdb/status.h"
namespace rocksdb {
class Env;
class Logger;
// DeleteScheduler allow 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:
virtual ~DeleteScheduler() {}
// Return delete rate limit in bytes per second
virtual int64_t GetRateBytesPerSecond() = 0;
// Move file to trash directory and schedule it's deletion
virtual Status DeleteFile(const std::string& fname) = 0;
// Return a map containing errors that happened in the background thread
// file_path => error status
virtual std::map<std::string, Status> GetBackgroundErrors() = 0;
// Wait for all files being deleteing in the background to finish or for
// destructor to be called.
virtual void WaitForEmptyTrash() = 0;
};
// Create a new DeleteScheduler that can be shared among multiple RocksDB
// instances to control the file deletion rate.
//
// @env: Pointer to Env object, please see "rocksdb/env.h".
// @trash_dir: Path to the directory where deleted files will be moved into
// to be deleted in a background thread while applying rate limiting. If this
// directory dont exist, it will be created. This directory should not be
// used by any other process or any other DeleteScheduler.
// @rate_bytes_per_sec: How many bytes should be deleted per second, If this
// value is set to 1024 (1 Kb / sec) and we deleted a file of size 4 Kb
// in 1 second, we will wait for another 3 seconds before we delete other
// files, Set to 0 to disable rate limiting.
// @info_log: If not nullptr, info_log will be used to log errors.
// @delete_exisitng_trash: If set to true, the newly created DeleteScheduler
// will delete files that already exist in trash_dir.
// @status: If not nullptr, status will contain any errors that happened during
// creating the missing trash_dir or deleting existing files in trash.
extern DeleteScheduler* NewDeleteScheduler(
Env* env, const std::string& trash_dir, int64_t rate_bytes_per_sec,
std::shared_ptr<Logger> info_log = nullptr,
bool delete_exisitng_trash = true, Status* status = nullptr);
} // namespace rocksdb
|