rocksdb/file/filename.h
Cheng Chang ee50b8d499 Be able to decrease background thread's CPU priority when creating database backup (#6602)
Summary:
When creating a database backup, the background threads will not only consume IO resources by copying files, but also consuming CPU such as by computing checksums. During peak times, the CPU consumption by the background threads might affect online queries.

This PR makes it possible to decrease CPU priority of these threads when creating a new backup.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6602

Test Plan: make check

Reviewed By: siying, zhichao-cao

Differential Revision: D20683216

Pulled By: cheng-chang

fbshipit-source-id: 9978b9ed9488e8ce135e90ca083e5b4b7221fd84
2020-03-28 19:07:25 -07:00

195 lines
7.5 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).
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
//
// File names used by DB code
#pragma once
#include <stdint.h>
#include <unordered_map>
#include <string>
#include <vector>
#include "options/db_options.h"
#include "port/port.h"
#include "rocksdb/file_system.h"
#include "rocksdb/options.h"
#include "rocksdb/slice.h"
#include "rocksdb/status.h"
#include "rocksdb/transaction_log.h"
namespace ROCKSDB_NAMESPACE {
class Env;
class Directory;
class WritableFileWriter;
#ifdef OS_WIN
const char kFilePathSeparator = '\\';
#else
const char kFilePathSeparator = '/';
#endif
enum FileType {
kLogFile,
kDBLockFile,
kTableFile,
kDescriptorFile,
kCurrentFile,
kTempFile,
kInfoLogFile, // Either the current one, or an old one
kMetaDatabase,
kIdentityFile,
kOptionsFile,
kBlobFile
};
// Return the name of the log file with the specified number
// in the db named by "dbname". The result will be prefixed with
// "dbname".
extern std::string LogFileName(const std::string& dbname, uint64_t number);
extern std::string LogFileName(uint64_t number);
extern std::string BlobFileName(const std::string& bdirname, uint64_t number);
extern std::string BlobFileName(const std::string& dbname,
const std::string& blob_dir, uint64_t number);
static const std::string ARCHIVAL_DIR = "archive";
extern std::string ArchivalDirectory(const std::string& dbname);
// Return the name of the archived log file with the specified number
// in the db named by "dbname". The result will be prefixed with "dbname".
extern std::string ArchivedLogFileName(const std::string& dbname,
uint64_t num);
extern std::string MakeTableFileName(const std::string& name, uint64_t number);
extern std::string MakeTableFileName(uint64_t number);
// Return the name of sstable with LevelDB suffix
// created from RocksDB sstable suffixed name
extern std::string Rocks2LevelTableFileName(const std::string& fullname);
// the reverse function of MakeTableFileName
// TODO(yhchiang): could merge this function with ParseFileName()
extern uint64_t TableFileNameToNumber(const std::string& name);
// Return the name of the sstable with the specified number
// in the db named by "dbname". The result will be prefixed with
// "dbname".
extern std::string TableFileName(const std::vector<DbPath>& db_paths,
uint64_t number, uint32_t path_id);
// Sufficient buffer size for FormatFileNumber.
const size_t kFormatFileNumberBufSize = 38;
extern void FormatFileNumber(uint64_t number, uint32_t path_id, char* out_buf,
size_t out_buf_size);
// Return the name of the descriptor file for the db named by
// "dbname" and the specified incarnation number. The result will be
// prefixed with "dbname".
extern std::string DescriptorFileName(const std::string& dbname,
uint64_t number);
// Return the name of the current file. This file contains the name
// of the current manifest file. The result will be prefixed with
// "dbname".
extern std::string CurrentFileName(const std::string& dbname);
// Return the name of the lock file for the db named by
// "dbname". The result will be prefixed with "dbname".
extern std::string LockFileName(const std::string& dbname);
// Return the name of a temporary file owned by the db named "dbname".
// The result will be prefixed with "dbname".
extern std::string TempFileName(const std::string& dbname, uint64_t number);
// A helper structure for prefix of info log names.
struct InfoLogPrefix {
char buf[260];
Slice prefix;
// Prefix with DB absolute path encoded
explicit InfoLogPrefix(bool has_log_dir, const std::string& db_absolute_path);
// Default Prefix
explicit InfoLogPrefix();
};
// Return the name of the info log file for "dbname".
extern std::string InfoLogFileName(const std::string& dbname,
const std::string& db_path = "",
const std::string& log_dir = "");
// Return the name of the old info log file for "dbname".
extern std::string OldInfoLogFileName(const std::string& dbname, uint64_t ts,
const std::string& db_path = "",
const std::string& log_dir = "");
static const std::string kOptionsFileNamePrefix = "OPTIONS-";
static const std::string kTempFileNameSuffix = "dbtmp";
// Return a options file name given the "dbname" and file number.
// Format: OPTIONS-[number].dbtmp
extern std::string OptionsFileName(const std::string& dbname,
uint64_t file_num);
// Return a temp options file name given the "dbname" and file number.
// Format: OPTIONS-[number]
extern std::string TempOptionsFileName(const std::string& dbname,
uint64_t file_num);
// Return the name to use for a metadatabase. The result will be prefixed with
// "dbname".
extern std::string MetaDatabaseName(const std::string& dbname,
uint64_t number);
// Return the name of the Identity file which stores a unique number for the db
// that will get regenerated if the db loses all its data and is recreated fresh
// either from a backup-image or empty
extern std::string IdentityFileName(const std::string& dbname);
// If filename is a rocksdb file, store the type of the file in *type.
// The number encoded in the filename is stored in *number. If the
// filename was successfully parsed, returns true. Else return false.
// info_log_name_prefix is the path of info logs.
extern bool ParseFileName(const std::string& filename, uint64_t* number,
const Slice& info_log_name_prefix, FileType* type,
WalFileType* log_type = nullptr);
// Same as previous function, but skip info log files.
extern bool ParseFileName(const std::string& filename, uint64_t* number,
FileType* type, WalFileType* log_type = nullptr);
// Make the CURRENT file point to the descriptor file with the
// specified number.
extern IOStatus SetCurrentFile(FileSystem* fs, const std::string& dbname,
uint64_t descriptor_number,
FSDirectory* directory_to_fsync);
// Make the IDENTITY file for the db
extern Status SetIdentityFile(Env* env, const std::string& dbname,
const std::string& db_id = {});
// Sync manifest file `file`.
extern IOStatus SyncManifest(Env* env, const ImmutableDBOptions* db_options,
WritableFileWriter* file);
// Return list of file names of info logs in `file_names`.
// The list only contains file name. The parent directory name is stored
// in `parent_dir`.
// `db_log_dir` should be the one as in options.db_log_dir
extern Status GetInfoLogFiles(Env* env, const std::string& db_log_dir,
const std::string& dbname,
std::string* parent_dir,
std::vector<std::string>* file_names);
extern std::string NormalizePath(const std::string& path);
} // namespace ROCKSDB_NAMESPACE