rocksdb/include/rocksdb/sst_file_manager.h
Siying Dong 3c327ac2d0 Change RocksDB License
Summary: Closes https://github.com/facebook/rocksdb/pull/2589

Differential Revision: D5431502

Pulled By: siying

fbshipit-source-id: 8ebf8c87883daa9daa54b2303d11ce01ab1f6f75
2017-07-15 16:11:23 -07:00

86 lines
3.3 KiB
C++

// 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 <memory>
#include <string>
#include <unordered_map>
#include "rocksdb/status.h"
namespace rocksdb {
class Env;
class Logger;
// SstFileManager is used to track SST files in the DB and control there
// deletion rate.
// All SstFileManager public functions are thread-safe.
class SstFileManager {
public:
virtual ~SstFileManager() {}
// Update the maximum allowed space that should be used by RocksDB, if
// the total size of the SST files exceeds max_allowed_space, writes to
// RocksDB will fail.
//
// Setting max_allowed_space to 0 will disable this feature, maximum allowed
// space will be infinite (Default value).
//
// thread-safe.
virtual void SetMaxAllowedSpaceUsage(uint64_t max_allowed_space) = 0;
// Return true if the total size of SST files exceeded the maximum allowed
// space usage.
//
// thread-safe.
virtual bool IsMaxAllowedSpaceReached() = 0;
// Return the total size of all tracked files.
// thread-safe
virtual uint64_t GetTotalSize() = 0;
// Return a map containing all tracked files and there corresponding sizes.
// thread-safe
virtual std::unordered_map<std::string, uint64_t> GetTrackedFiles() = 0;
// Return delete rate limit in bytes per second.
// thread-safe
virtual int64_t GetDeleteRateBytesPerSecond() = 0;
// Update the delete rate limit in bytes per second.
// zero means disable delete rate limiting and delete files immediately
// thread-safe
virtual void SetDeleteRateBytesPerSecond(int64_t delete_rate) = 0;
};
// Create a new SstFileManager that can be shared among multiple RocksDB
// instances to track SST file and control there deletion rate.
//
// @param env: Pointer to Env object, please see "rocksdb/env.h".
// @param info_log: If not nullptr, info_log will be used to log errors.
//
// == Deletion rate limiting specific arguments ==
// @param trash_dir: Path to the directory where deleted files will be moved
// to be deleted in a background thread while applying rate limiting. If this
// directory doesn't exist, it will be created. This directory should not be
// used by any other process or any other SstFileManager, Set to "" to
// disable deletion rate limiting.
// @param 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 deletion rate limiting.
// @param delete_existing_trash: If set to true, the newly created
// SstFileManager will delete files that already exist in trash_dir.
// @param status: If not nullptr, status will contain any errors that happened
// during creating the missing trash_dir or deleting existing files in trash.
extern SstFileManager* NewSstFileManager(
Env* env, std::shared_ptr<Logger> info_log = nullptr,
std::string trash_dir = "", int64_t rate_bytes_per_sec = 0,
bool delete_existing_trash = true, Status* status = nullptr);
} // namespace rocksdb