rocksdb/table/table_builder.h
Sagar Vemuri d3d20dcdca Periodic Compactions (#5166)
Summary:
Introducing Periodic Compactions.

This feature allows all the files in a CF to be periodically compacted. It could help in catching any corruptions that could creep into the DB proactively as every file is constantly getting re-compacted.  And also, of course, it helps to cleanup data older than certain threshold.

- Introduced a new option `periodic_compaction_time` to control how long a file can live without being compacted in a CF.
- This works across all levels.
- The files are put in the same level after going through the compaction. (Related files in the same level are picked up as `ExpandInputstoCleanCut` is used).
- Compaction filters, if any, are invoked as usual.
- A new table property, `file_creation_time`, is introduced to implement this feature. This property is set to the time at which the SST file was created (and that time is given by the underlying Env/OS).

This feature can be enabled on its own, or in conjunction with `ttl`. It is possible to set a different time threshold for the bottom level when used in conjunction with ttl. Since `ttl` works only on 0 to last but one levels, you could set `ttl` to, say, 1 day, and `periodic_compaction_time` to, say, 7 days. Since `ttl < periodic_compaction_time` all files in last but one levels keep getting picked up based on ttl, and almost never based on periodic_compaction_time. The files in the bottom level get picked up for compaction based on `periodic_compaction_time`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5166

Differential Revision: D14884441

Pulled By: sagar0

fbshipit-source-id: 408426cbacb409c06386a98632dcf90bfa1bda47
2019-04-10 19:31:18 -07:00

159 lines
6.2 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.
#pragma once
#include <stdint.h>
#include <string>
#include <utility>
#include <vector>
#include "db/dbformat.h"
#include "db/table_properties_collector.h"
#include "options/cf_options.h"
#include "rocksdb/options.h"
#include "rocksdb/table_properties.h"
#include "util/file_reader_writer.h"
namespace rocksdb {
class Slice;
class Status;
struct TableReaderOptions {
// @param skip_filters Disables loading/accessing the filter block
TableReaderOptions(const ImmutableCFOptions& _ioptions,
const SliceTransform* _prefix_extractor,
const EnvOptions& _env_options,
const InternalKeyComparator& _internal_comparator,
bool _skip_filters = false, bool _immortal = false,
int _level = -1)
: TableReaderOptions(_ioptions, _prefix_extractor, _env_options,
_internal_comparator, _skip_filters, _immortal,
_level, 0 /* _largest_seqno */) {}
// @param skip_filters Disables loading/accessing the filter block
TableReaderOptions(const ImmutableCFOptions& _ioptions,
const SliceTransform* _prefix_extractor,
const EnvOptions& _env_options,
const InternalKeyComparator& _internal_comparator,
bool _skip_filters, bool _immortal, int _level,
SequenceNumber _largest_seqno)
: ioptions(_ioptions),
prefix_extractor(_prefix_extractor),
env_options(_env_options),
internal_comparator(_internal_comparator),
skip_filters(_skip_filters),
immortal(_immortal),
level(_level),
largest_seqno(_largest_seqno) {}
const ImmutableCFOptions& ioptions;
const SliceTransform* prefix_extractor;
const EnvOptions& env_options;
const InternalKeyComparator& internal_comparator;
// This is only used for BlockBasedTable (reader)
bool skip_filters;
// Whether the table will be valid as long as the DB is open
bool immortal;
// what level this table/file is on, -1 for "not set, don't know"
int level;
// largest seqno in the table
SequenceNumber largest_seqno;
};
struct TableBuilderOptions {
TableBuilderOptions(
const ImmutableCFOptions& _ioptions, const MutableCFOptions& _moptions,
const InternalKeyComparator& _internal_comparator,
const std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
_int_tbl_prop_collector_factories,
CompressionType _compression_type, uint64_t _sample_for_compression,
const CompressionOptions& _compression_opts, bool _skip_filters,
const std::string& _column_family_name, int _level,
const uint64_t _creation_time = 0, const int64_t _oldest_key_time = 0,
const uint64_t _target_file_size = 0,
const uint64_t _file_creation_time = 0)
: ioptions(_ioptions),
moptions(_moptions),
internal_comparator(_internal_comparator),
int_tbl_prop_collector_factories(_int_tbl_prop_collector_factories),
compression_type(_compression_type),
sample_for_compression(_sample_for_compression),
compression_opts(_compression_opts),
skip_filters(_skip_filters),
column_family_name(_column_family_name),
level(_level),
creation_time(_creation_time),
oldest_key_time(_oldest_key_time),
target_file_size(_target_file_size),
file_creation_time(_file_creation_time) {}
const ImmutableCFOptions& ioptions;
const MutableCFOptions& moptions;
const InternalKeyComparator& internal_comparator;
const std::vector<std::unique_ptr<IntTblPropCollectorFactory>>*
int_tbl_prop_collector_factories;
CompressionType compression_type;
uint64_t sample_for_compression;
const CompressionOptions& compression_opts;
bool skip_filters; // only used by BlockBasedTableBuilder
const std::string& column_family_name;
int level; // what level this table/file is on, -1 for "not set, don't know"
const uint64_t creation_time;
const int64_t oldest_key_time;
const uint64_t target_file_size;
const uint64_t file_creation_time;
};
// TableBuilder provides the interface used to build a Table
// (an immutable and sorted map from keys to values).
//
// Multiple threads can invoke const methods on a TableBuilder without
// external synchronization, but if any of the threads may call a
// non-const method, all threads accessing the same TableBuilder must use
// external synchronization.
class TableBuilder {
public:
// REQUIRES: Either Finish() or Abandon() has been called.
virtual ~TableBuilder() {}
// Add key,value to the table being constructed.
// REQUIRES: key is after any previously added key according to comparator.
// REQUIRES: Finish(), Abandon() have not been called
virtual void Add(const Slice& key, const Slice& value) = 0;
// Return non-ok iff some error has been detected.
virtual Status status() const = 0;
// Finish building the table.
// REQUIRES: Finish(), Abandon() have not been called
virtual Status Finish() = 0;
// Indicate that the contents of this builder should be abandoned.
// If the caller is not going to call Finish(), it must call Abandon()
// before destroying this builder.
// REQUIRES: Finish(), Abandon() have not been called
virtual void Abandon() = 0;
// Number of calls to Add() so far.
virtual uint64_t NumEntries() const = 0;
// Size of the file generated so far. If invoked after a successful
// Finish() call, returns the size of the final generated file.
virtual uint64_t FileSize() const = 0;
// If the user defined table properties collector suggest the file to
// be further compacted.
virtual bool NeedCompact() const { return false; }
// Returns table properties
virtual TableProperties GetTableProperties() const = 0;
};
} // namespace rocksdb