2016-02-09 23:12:00 +00:00
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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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2017-07-15 23:03:42 +00:00
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#pragma once
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2015-08-25 19:29:44 +00:00
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CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
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#include <memory>
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#include <set>
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2015-08-25 19:29:44 +00:00
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#include <string>
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CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
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#include <unordered_set>
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2015-08-25 19:29:44 +00:00
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#include <vector>
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CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
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2019-05-31 18:52:59 +00:00
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#include "db/compaction/compaction.h"
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2015-08-25 19:29:44 +00:00
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#include "db/version_set.h"
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2017-04-06 02:02:00 +00:00
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#include "options/cf_options.h"
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2014-02-05 00:31:18 +00:00
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#include "rocksdb/env.h"
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2015-08-25 19:29:44 +00:00
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#include "rocksdb/options.h"
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#include "rocksdb/status.h"
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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2020-02-20 20:07:53 +00:00
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namespace ROCKSDB_NAMESPACE {
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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2019-05-28 19:18:31 +00:00
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// The file contains an abstract class CompactionPicker, and its two
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// sub-classes LevelCompactionPicker and NullCompactionPicker, as
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// well as some helper functions used by them.
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Buffer info logs when picking compactions and write them out after releasing the mutex
Summary: Now while the background thread is picking compactions, it writes out multiple info_logs, especially for universal compaction, which introduces a chance of waiting log writing in mutex, which is bad. To remove this risk, write all those info logs to a buffer and flush it after releasing the mutex.
Test Plan:
make all check
check the log lines while running some tests that trigger compactions.
Reviewers: haobo, igor, dhruba
Reviewed By: dhruba
CC: i.am.jin.lei, dhruba, yhchiang, leveldb, nkg-
Differential Revision: https://reviews.facebook.net/D16515
2014-03-04 22:32:55 +00:00
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class LogBuffer;
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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class Compaction;
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2014-10-27 22:49:46 +00:00
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class VersionStorageInfo;
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CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
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struct CompactionInputFiles;
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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2019-05-28 19:18:31 +00:00
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// An abstract class to pick compactions from an existing LSM-tree.
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//
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// Each compaction style inherits the class and implement the
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// interface to form automatic compactions. If NeedCompaction() is true,
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// then call PickCompaction() to find what files need to be compacted
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// and where to put the output files.
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//
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// Non-virtual functions CompactRange() and CompactFiles() are used to
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// pick files to compact based on users' DB::CompactRange() and
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// DB::CompactFiles() requests, respectively. There is little
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// compaction style specific logic for them.
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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class CompactionPicker {
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public:
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2014-10-01 23:19:16 +00:00
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CompactionPicker(const ImmutableCFOptions& ioptions,
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const InternalKeyComparator* icmp);
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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virtual ~CompactionPicker();
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// Pick level and inputs for a new compaction.
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// Returns nullptr if there is no compaction to be done.
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// Otherwise returns a pointer to a heap-allocated object that
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// describes the compaction. Caller should delete the result.
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Fix corruption with intra-L0 on ingested files (#5958)
Summary:
## Problem Description
Our process was abort when it call `CheckConsistency`. And the information in `stderr` show that "`L0 files seqno 3001491972 3004797440 vs. 3002875611 3004524421` ". Here are the causes of the accident I investigated.
* RocksDB will call `CheckConsistency` whenever `MANIFEST` file is update. It will check sequence number interval of every file, except files which were ingested.
* When one file is ingested into RocksDB, it will be assigned the value of global sequence number, and the minimum and maximum seqno of this file are equal, which are both equal to global sequence number.
* `CheckConsistency` determines whether the file is ingested by whether the smallest and largest seqno of an sstable file are equal.
* If IntraL0Compaction picks one sst which was ingested just now and compacted it into another sst, the `smallest_seqno` of this new file will be smaller than his `largest_seqno`.
* If more than one ingested file was ingested before memtable schedule flush, and they all compact into one new sstable file by `IntraL0Compaction`. The sequence interval of this new file will be included in the interval of the memtable. So `CheckConsistency` will return a `Corruption`.
* If a sstable was ingested after the memtable was schedule to flush, which would assign a larger seqno to it than memtable. Then the file was compacted with other files (these files were all flushed before the memtable) in L0 into one file. This compaction start before the flush job of memtable start, but completed after the flush job finish. So this new file produced by the compaction (we call it s1) would have a larger interval of sequence number than the file produced by flush (we call it s2). **But there was still some data in s1 written into RocksDB before the s2, so it's possible that some data in s2 was cover by old data in s1.** Of course, it would also make a `Corruption` because of overlap of seqno. There is the relationship of the files:
> s1.smallest_seqno < s2.smallest_seqno < s2.largest_seqno < s1.largest_seqno
So I skip pick sst file which was ingested in function `FindIntraL0Compaction `
## Reason
Here is my bug report: https://github.com/facebook/rocksdb/issues/5913
There are two situations that can cause the check to fail.
### First situation:
- First we ingest five external sst into Rocksdb, and they happened to be ingested in L0. and there had been some data in memtable, which make the smallest sequence number of memtable is less than which of sst that we ingest.
- If there had been one compaction job which compacted sst from L0 to L1, `LevelCompactionPicker` would trigger a `IntraL0Compaction` which would compact this five sst from L0 to L0. We call this sst A, which was merged from five ingested sst.
- Then some data was put into memtable, and memtable was flushed to L0. We called this sst B.
- RocksDB check consistency , and find the `smallest_seqno` of B is less than that of A and crash. Because A was merged from five sst, the smallest sequence number of it was less than the biggest sequece number of itself, so RocksDB could not tell if A was produce by ingested.
### Secondary situaion
- First we have flushed many sst in L0, we call them [s1, s2, s3].
- There is an immutable memtable request to be flushed, but because flush thread is busy, so it has not been picked. we call it m1. And at the moment, one sst is ingested into L0. We call it s4. Because s4 is ingested after m1 became immutable memtable, so it has a larger log sequence number than m1.
- m1 is flushed in L0. because it is small, this flush job finish quickly. we call it s5.
- [s1, s2, s3, s4] are compacted into one sst to L0, by IntraL0Compaction. We call it s6.
- compacted 4@0 files to L0
- When s6 is added into manifest, the corruption happened. because the largest sequence number of s6 is equal to s4, and they are both larger than that of s5. But because s1 is older than m1, so the smallest sequence number of s6 is smaller than that of s5.
- s6.smallest_seqno < s5.smallest_seqno < s5.largest_seqno < s6.largest_seqno
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5958
Differential Revision: D18601316
fbshipit-source-id: 5fe54b3c9af52a2e1400728f565e895cde1c7267
2019-11-19 23:07:49 +00:00
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virtual Compaction* PickCompaction(
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const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
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VersionStorageInfo* vstorage, LogBuffer* log_buffer,
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SequenceNumber earliest_memtable_seqno = kMaxSequenceNumber) = 0;
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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// Return a compaction object for compacting the range [begin,end] in
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// the specified level. Returns nullptr if there is nothing in that
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// level that overlaps the specified range. Caller should delete
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// the result.
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//
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// The returned Compaction might not include the whole requested range.
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// In that case, compaction_end will be set to the next key that needs
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// compacting. In case the compaction will compact the whole range,
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// compaction_end will be set to nullptr.
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// Client is responsible for compaction_end storage -- when called,
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// *compaction_end should point to valid InternalKey!
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2014-10-01 23:19:16 +00:00
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virtual Compaction* CompactRange(
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2014-10-27 22:49:46 +00:00
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const std::string& cf_name, const MutableCFOptions& mutable_cf_options,
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VersionStorageInfo* vstorage, int input_level, int output_level,
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2019-04-17 06:29:32 +00:00
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const CompactRangeOptions& compact_range_options,
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2018-04-27 18:48:21 +00:00
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const InternalKey* begin, const InternalKey* end,
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2019-04-17 06:29:32 +00:00
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InternalKey** compaction_end, bool* manual_conflict,
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uint64_t max_file_num_to_ignore);
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CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
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CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
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// The maximum allowed output level. Default value is NumberLevels() - 1.
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2016-05-17 20:11:56 +00:00
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virtual int MaxOutputLevel() const { return NumberLevels() - 1; }
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CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
|
2014-11-13 23:21:04 +00:00
|
|
|
virtual bool NeedsCompaction(const VersionStorageInfo* vstorage) const = 0;
|
2014-11-13 21:41:43 +00:00
|
|
|
|
2016-05-17 20:11:56 +00:00
|
|
|
// Sanitize the input set of compaction input files.
|
|
|
|
// When the input parameters do not describe a valid compaction, the
|
|
|
|
// function will try to fix the input_files by adding necessary
|
|
|
|
// files. If it's not possible to conver an invalid input_files
|
|
|
|
// into a valid one by adding more files, the function will return a
|
|
|
|
// non-ok status with specific reason.
|
2014-11-13 21:45:33 +00:00
|
|
|
#ifndef ROCKSDB_LITE
|
2016-05-17 20:11:56 +00:00
|
|
|
Status SanitizeCompactionInputFiles(std::unordered_set<uint64_t>* input_files,
|
|
|
|
const ColumnFamilyMetaData& cf_meta,
|
|
|
|
const int output_level) const;
|
2014-11-13 21:45:33 +00:00
|
|
|
#endif // ROCKSDB_LITE
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
// Free up the files that participated in a compaction
|
2016-03-09 00:46:41 +00:00
|
|
|
//
|
|
|
|
// Requirement: DB mutex held
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
void ReleaseCompactionFiles(Compaction* c, Status status);
|
|
|
|
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
// Returns true if any one of the specified files are being compacted
|
2017-04-07 03:06:34 +00:00
|
|
|
bool AreFilesInCompaction(const std::vector<FileMetaData*>& files);
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
|
2015-08-25 19:29:44 +00:00
|
|
|
// Takes a list of CompactionInputFiles and returns a (manual) Compaction
|
|
|
|
// object.
|
2017-09-13 22:31:34 +00:00
|
|
|
//
|
|
|
|
// Caller must provide a set of input files that has been passed through
|
|
|
|
// `SanitizeCompactionInputFiles` earlier. The lock should not be released
|
|
|
|
// between that call and this one.
|
2017-04-07 03:06:34 +00:00
|
|
|
Compaction* CompactFiles(const CompactionOptions& compact_options,
|
|
|
|
const std::vector<CompactionInputFiles>& input_files,
|
|
|
|
int output_level, VersionStorageInfo* vstorage,
|
|
|
|
const MutableCFOptions& mutable_cf_options,
|
|
|
|
uint32_t output_path_id);
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
|
|
|
|
// Converts a set of compaction input file numbers into
|
|
|
|
// a list of CompactionInputFiles.
|
|
|
|
Status GetCompactionInputsFromFileNumbers(
|
Make Compaction class easier to use
Summary:
The goal of this diff is to make Compaction class easier to use. This should also make new compaction algorithms easier to write (like CompactFiles from @yhchiang and dynamic leveled and multi-leveled universal from @sdong).
Here are couple of things demonstrating that Compaction class is hard to use:
1. we have two constructors of Compaction class
2. there's this thing called grandparents_, but it appears to only be setup for leveled compaction and not compactfiles
3. it's easy to introduce a subtle and dangerous bug like this: D36225
4. SetupBottomMostLevel() is hard to understand and it shouldn't be. See this comment: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction.cc#L236-L241. It also made it harder for @yhchiang to write CompactFiles, as evidenced by this: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction_picker.cc#L204-L210
The problem is that we create Compaction object, which holds a lot of state, and then pass it around to some functions. After those functions are done mutating, then we call couple of functions on Compaction object, like SetupBottommostLevel() and MarkFilesBeingCompacted(). It is very hard to see what's happening with all that Compaction's state while it's travelling across different functions. If you're writing a new PickCompaction() function you need to try really hard to understand what are all the functions you need to run on Compaction object and what state you need to setup.
My proposed solution is to make important parts of Compaction immutable after construction. PickCompaction() should calculate compaction inputs and then pass them onto Compaction object once they are finalized. That makes it easy to create a new compaction -- just provide all the parameters to the constructor and you're done. No need to call confusing functions after you created your object.
This diff doesn't fully achieve that goal, but it comes pretty close. Here are some of the changes:
* have one Compaction constructor instead of two.
* inputs_ is constant after construction
* MarkFilesBeingCompacted() is now private to Compaction class and automatically called on construction/destruction.
* SetupBottommostLevel() is gone. Compaction figures it out on its own based on the input.
* CompactionPicker's functions are not passing around Compaction object anymore. They are only passing around the state that they need.
Test Plan:
make check
make asan_check
make valgrind_check
Reviewers: rven, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36687
2015-04-10 22:01:54 +00:00
|
|
|
std::vector<CompactionInputFiles>* input_files,
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
std::unordered_set<uint64_t>* input_set,
|
|
|
|
const VersionStorageInfo* vstorage,
|
|
|
|
const CompactionOptions& compact_options) const;
|
|
|
|
|
2015-09-14 18:03:37 +00:00
|
|
|
// Is there currently a compaction involving level 0 taking place
|
|
|
|
bool IsLevel0CompactionInProgress() const {
|
|
|
|
return !level0_compactions_in_progress_.empty();
|
|
|
|
}
|
|
|
|
|
2016-10-13 17:49:06 +00:00
|
|
|
// Return true if the passed key range overlap with a compaction output
|
|
|
|
// that is currently running.
|
|
|
|
bool RangeOverlapWithCompaction(const Slice& smallest_user_key,
|
|
|
|
const Slice& largest_user_key,
|
|
|
|
int level) const;
|
|
|
|
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
// Stores the minimal range that covers all entries in inputs in
|
|
|
|
// *smallest, *largest.
|
|
|
|
// REQUIRES: inputs is not empty
|
2016-05-17 20:11:56 +00:00
|
|
|
void GetRange(const CompactionInputFiles& inputs, InternalKey* smallest,
|
2016-10-13 17:49:06 +00:00
|
|
|
InternalKey* largest) const;
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
|
|
|
|
// Stores the minimal range that covers all entries in inputs1 and inputs2
|
|
|
|
// in *smallest, *largest.
|
|
|
|
// REQUIRES: inputs is not empty
|
2015-05-05 16:57:47 +00:00
|
|
|
void GetRange(const CompactionInputFiles& inputs1,
|
2016-05-17 20:11:56 +00:00
|
|
|
const CompactionInputFiles& inputs2, InternalKey* smallest,
|
2016-10-13 17:49:06 +00:00
|
|
|
InternalKey* largest) const;
|
|
|
|
|
|
|
|
// Stores the minimal range that covers all entries in inputs
|
|
|
|
// in *smallest, *largest.
|
|
|
|
// REQUIRES: inputs is not empty (at least on entry have one file)
|
|
|
|
void GetRange(const std::vector<CompactionInputFiles>& inputs,
|
|
|
|
InternalKey* smallest, InternalKey* largest) const;
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
|
2016-12-07 19:42:49 +00:00
|
|
|
int NumberLevels() const { return ioptions_.num_levels; }
|
|
|
|
|
2014-01-17 20:02:03 +00:00
|
|
|
// Add more files to the inputs on "level" to make sure that
|
|
|
|
// no newer version of a key is compacted to "level+1" while leaving an older
|
|
|
|
// version in a "level". Otherwise, any Get() will search "level" first,
|
|
|
|
// and will likely return an old/stale value for the key, since it always
|
|
|
|
// searches in increasing order of level to find the value. This could
|
|
|
|
// also scramble the order of merge operands. This function should be
|
|
|
|
// called any time a new Compaction is created, and its inputs_[0] are
|
|
|
|
// populated.
|
|
|
|
//
|
|
|
|
// Will return false if it is impossible to apply this compaction.
|
2017-04-07 03:06:34 +00:00
|
|
|
bool ExpandInputsToCleanCut(const std::string& cf_name,
|
Make Compaction class easier to use
Summary:
The goal of this diff is to make Compaction class easier to use. This should also make new compaction algorithms easier to write (like CompactFiles from @yhchiang and dynamic leveled and multi-leveled universal from @sdong).
Here are couple of things demonstrating that Compaction class is hard to use:
1. we have two constructors of Compaction class
2. there's this thing called grandparents_, but it appears to only be setup for leveled compaction and not compactfiles
3. it's easy to introduce a subtle and dangerous bug like this: D36225
4. SetupBottomMostLevel() is hard to understand and it shouldn't be. See this comment: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction.cc#L236-L241. It also made it harder for @yhchiang to write CompactFiles, as evidenced by this: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction_picker.cc#L204-L210
The problem is that we create Compaction object, which holds a lot of state, and then pass it around to some functions. After those functions are done mutating, then we call couple of functions on Compaction object, like SetupBottommostLevel() and MarkFilesBeingCompacted(). It is very hard to see what's happening with all that Compaction's state while it's travelling across different functions. If you're writing a new PickCompaction() function you need to try really hard to understand what are all the functions you need to run on Compaction object and what state you need to setup.
My proposed solution is to make important parts of Compaction immutable after construction. PickCompaction() should calculate compaction inputs and then pass them onto Compaction object once they are finalized. That makes it easy to create a new compaction -- just provide all the parameters to the constructor and you're done. No need to call confusing functions after you created your object.
This diff doesn't fully achieve that goal, but it comes pretty close. Here are some of the changes:
* have one Compaction constructor instead of two.
* inputs_ is constant after construction
* MarkFilesBeingCompacted() is now private to Compaction class and automatically called on construction/destruction.
* SetupBottommostLevel() is gone. Compaction figures it out on its own based on the input.
* CompactionPicker's functions are not passing around Compaction object anymore. They are only passing around the state that they need.
Test Plan:
make check
make asan_check
make valgrind_check
Reviewers: rven, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36687
2015-04-10 22:01:54 +00:00
|
|
|
VersionStorageInfo* vstorage,
|
2018-10-16 06:20:15 +00:00
|
|
|
CompactionInputFiles* inputs,
|
|
|
|
InternalKey** next_smallest = nullptr);
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
|
|
|
|
// Returns true if any one of the parent files are being compacted
|
2017-04-07 03:06:34 +00:00
|
|
|
bool IsRangeInCompaction(VersionStorageInfo* vstorage,
|
|
|
|
const InternalKey* smallest,
|
|
|
|
const InternalKey* largest, int level, int* index);
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
|
2016-10-13 17:49:06 +00:00
|
|
|
// Returns true if the key range that `inputs` files cover overlap with the
|
|
|
|
// key range of a currently running compaction.
|
|
|
|
bool FilesRangeOverlapWithCompaction(
|
|
|
|
const std::vector<CompactionInputFiles>& inputs, int level) const;
|
|
|
|
|
Make Compaction class easier to use
Summary:
The goal of this diff is to make Compaction class easier to use. This should also make new compaction algorithms easier to write (like CompactFiles from @yhchiang and dynamic leveled and multi-leveled universal from @sdong).
Here are couple of things demonstrating that Compaction class is hard to use:
1. we have two constructors of Compaction class
2. there's this thing called grandparents_, but it appears to only be setup for leveled compaction and not compactfiles
3. it's easy to introduce a subtle and dangerous bug like this: D36225
4. SetupBottomMostLevel() is hard to understand and it shouldn't be. See this comment: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction.cc#L236-L241. It also made it harder for @yhchiang to write CompactFiles, as evidenced by this: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction_picker.cc#L204-L210
The problem is that we create Compaction object, which holds a lot of state, and then pass it around to some functions. After those functions are done mutating, then we call couple of functions on Compaction object, like SetupBottommostLevel() and MarkFilesBeingCompacted(). It is very hard to see what's happening with all that Compaction's state while it's travelling across different functions. If you're writing a new PickCompaction() function you need to try really hard to understand what are all the functions you need to run on Compaction object and what state you need to setup.
My proposed solution is to make important parts of Compaction immutable after construction. PickCompaction() should calculate compaction inputs and then pass them onto Compaction object once they are finalized. That makes it easy to create a new compaction -- just provide all the parameters to the constructor and you're done. No need to call confusing functions after you created your object.
This diff doesn't fully achieve that goal, but it comes pretty close. Here are some of the changes:
* have one Compaction constructor instead of two.
* inputs_ is constant after construction
* MarkFilesBeingCompacted() is now private to Compaction class and automatically called on construction/destruction.
* SetupBottommostLevel() is gone. Compaction figures it out on its own based on the input.
* CompactionPicker's functions are not passing around Compaction object anymore. They are only passing around the state that they need.
Test Plan:
make check
make asan_check
make valgrind_check
Reviewers: rven, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36687
2015-04-10 22:01:54 +00:00
|
|
|
bool SetupOtherInputs(const std::string& cf_name,
|
2014-10-27 22:49:46 +00:00
|
|
|
const MutableCFOptions& mutable_cf_options,
|
Make Compaction class easier to use
Summary:
The goal of this diff is to make Compaction class easier to use. This should also make new compaction algorithms easier to write (like CompactFiles from @yhchiang and dynamic leveled and multi-leveled universal from @sdong).
Here are couple of things demonstrating that Compaction class is hard to use:
1. we have two constructors of Compaction class
2. there's this thing called grandparents_, but it appears to only be setup for leveled compaction and not compactfiles
3. it's easy to introduce a subtle and dangerous bug like this: D36225
4. SetupBottomMostLevel() is hard to understand and it shouldn't be. See this comment: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction.cc#L236-L241. It also made it harder for @yhchiang to write CompactFiles, as evidenced by this: https://github.com/facebook/rocksdb/blob/afbafeaeaebfd27a0f3e992fee8e0c57d07658fa/db/compaction_picker.cc#L204-L210
The problem is that we create Compaction object, which holds a lot of state, and then pass it around to some functions. After those functions are done mutating, then we call couple of functions on Compaction object, like SetupBottommostLevel() and MarkFilesBeingCompacted(). It is very hard to see what's happening with all that Compaction's state while it's travelling across different functions. If you're writing a new PickCompaction() function you need to try really hard to understand what are all the functions you need to run on Compaction object and what state you need to setup.
My proposed solution is to make important parts of Compaction immutable after construction. PickCompaction() should calculate compaction inputs and then pass them onto Compaction object once they are finalized. That makes it easy to create a new compaction -- just provide all the parameters to the constructor and you're done. No need to call confusing functions after you created your object.
This diff doesn't fully achieve that goal, but it comes pretty close. Here are some of the changes:
* have one Compaction constructor instead of two.
* inputs_ is constant after construction
* MarkFilesBeingCompacted() is now private to Compaction class and automatically called on construction/destruction.
* SetupBottommostLevel() is gone. Compaction figures it out on its own based on the input.
* CompactionPicker's functions are not passing around Compaction object anymore. They are only passing around the state that they need.
Test Plan:
make check
make asan_check
make valgrind_check
Reviewers: rven, anthony, sdong, yhchiang
Reviewed By: yhchiang
Subscribers: sdong, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36687
2015-04-10 22:01:54 +00:00
|
|
|
VersionStorageInfo* vstorage,
|
|
|
|
CompactionInputFiles* inputs,
|
|
|
|
CompactionInputFiles* output_level_inputs,
|
|
|
|
int* parent_index, int base_index);
|
|
|
|
|
|
|
|
void GetGrandparents(VersionStorageInfo* vstorage,
|
|
|
|
const CompactionInputFiles& inputs,
|
|
|
|
const CompactionInputFiles& output_level_inputs,
|
|
|
|
std::vector<FileMetaData*>* grandparents);
|
2014-10-01 23:19:16 +00:00
|
|
|
|
2018-05-29 22:42:14 +00:00
|
|
|
void PickFilesMarkedForCompaction(const std::string& cf_name,
|
|
|
|
VersionStorageInfo* vstorage,
|
|
|
|
int* start_level, int* output_level,
|
|
|
|
CompactionInputFiles* start_level_inputs);
|
|
|
|
|
|
|
|
bool GetOverlappingL0Files(VersionStorageInfo* vstorage,
|
|
|
|
CompactionInputFiles* start_level_inputs,
|
|
|
|
int output_level, int* parent_index);
|
|
|
|
|
2017-04-07 03:06:34 +00:00
|
|
|
// Register this compaction in the set of running compactions
|
|
|
|
void RegisterCompaction(Compaction* c);
|
|
|
|
|
|
|
|
// Remove this compaction from the set of running compactions
|
|
|
|
void UnregisterCompaction(Compaction* c);
|
|
|
|
|
|
|
|
std::set<Compaction*>* level0_compactions_in_progress() {
|
|
|
|
return &level0_compactions_in_progress_;
|
|
|
|
}
|
|
|
|
std::unordered_set<Compaction*>* compactions_in_progress() {
|
|
|
|
return &compactions_in_progress_;
|
|
|
|
}
|
|
|
|
|
|
|
|
protected:
|
2014-10-01 23:19:16 +00:00
|
|
|
const ImmutableCFOptions& ioptions_;
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
|
2016-05-17 20:11:56 +00:00
|
|
|
// A helper function to SanitizeCompactionInputFiles() that
|
|
|
|
// sanitizes "input_files" by adding necessary files.
|
2014-11-13 21:45:33 +00:00
|
|
|
#ifndef ROCKSDB_LITE
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
virtual Status SanitizeCompactionInputFilesForAllLevels(
|
|
|
|
std::unordered_set<uint64_t>* input_files,
|
2016-05-17 20:11:56 +00:00
|
|
|
const ColumnFamilyMetaData& cf_meta, const int output_level) const;
|
2014-11-13 21:45:33 +00:00
|
|
|
#endif // ROCKSDB_LITE
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
|
2015-03-19 01:25:15 +00:00
|
|
|
// Keeps track of all compactions that are running on Level0.
|
2016-10-13 17:49:06 +00:00
|
|
|
// Protected by DB mutex
|
2015-03-19 01:25:15 +00:00
|
|
|
std::set<Compaction*> level0_compactions_in_progress_;
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
|
2016-10-13 17:49:06 +00:00
|
|
|
// Keeps track of all compactions that are running.
|
|
|
|
// Protected by DB mutex
|
|
|
|
std::unordered_set<Compaction*> compactions_in_progress_;
|
|
|
|
|
CompactionPicker
Summary:
This is a big one. This diff moves all the code related to picking compactions from VersionSet to new class CompactionPicker. Column families' compactions will be completely separate processes, so we need to have multiple CompactionPickers.
To make this easier to review, most of the code change is just copy/paste. There is also a small change not to use VersionSet::current_, but rather to take `Version* version` as a parameter. Most of the other code is exactly the same.
In future diffs, I will also make some improvements to CompactionPickers. I think the most important part will be encapsulating it better. Currently Version, VersionSet, Compaction and CompactionPicker are all friend classes, which makes it harder to change the implementation.
This diff depends on D15171, D15183, D15189 and D15201
Test Plan: `make check`
Reviewers: kailiu, sdong, dhruba, haobo
Reviewed By: kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15207
2014-01-16 21:03:52 +00:00
|
|
|
const InternalKeyComparator* const icmp_;
|
|
|
|
};
|
|
|
|
|
2014-11-26 23:45:11 +00:00
|
|
|
#ifndef ROCKSDB_LITE
|
2019-05-28 19:18:31 +00:00
|
|
|
// A dummy compaction that never triggers any automatic
|
|
|
|
// compaction.
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
class NullCompactionPicker : public CompactionPicker {
|
|
|
|
public:
|
|
|
|
NullCompactionPicker(const ImmutableCFOptions& ioptions,
|
2016-05-17 20:11:56 +00:00
|
|
|
const InternalKeyComparator* icmp)
|
|
|
|
: CompactionPicker(ioptions, icmp) {}
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
virtual ~NullCompactionPicker() {}
|
|
|
|
|
|
|
|
// Always return "nullptr"
|
Fix corruption with intra-L0 on ingested files (#5958)
Summary:
## Problem Description
Our process was abort when it call `CheckConsistency`. And the information in `stderr` show that "`L0 files seqno 3001491972 3004797440 vs. 3002875611 3004524421` ". Here are the causes of the accident I investigated.
* RocksDB will call `CheckConsistency` whenever `MANIFEST` file is update. It will check sequence number interval of every file, except files which were ingested.
* When one file is ingested into RocksDB, it will be assigned the value of global sequence number, and the minimum and maximum seqno of this file are equal, which are both equal to global sequence number.
* `CheckConsistency` determines whether the file is ingested by whether the smallest and largest seqno of an sstable file are equal.
* If IntraL0Compaction picks one sst which was ingested just now and compacted it into another sst, the `smallest_seqno` of this new file will be smaller than his `largest_seqno`.
* If more than one ingested file was ingested before memtable schedule flush, and they all compact into one new sstable file by `IntraL0Compaction`. The sequence interval of this new file will be included in the interval of the memtable. So `CheckConsistency` will return a `Corruption`.
* If a sstable was ingested after the memtable was schedule to flush, which would assign a larger seqno to it than memtable. Then the file was compacted with other files (these files were all flushed before the memtable) in L0 into one file. This compaction start before the flush job of memtable start, but completed after the flush job finish. So this new file produced by the compaction (we call it s1) would have a larger interval of sequence number than the file produced by flush (we call it s2). **But there was still some data in s1 written into RocksDB before the s2, so it's possible that some data in s2 was cover by old data in s1.** Of course, it would also make a `Corruption` because of overlap of seqno. There is the relationship of the files:
> s1.smallest_seqno < s2.smallest_seqno < s2.largest_seqno < s1.largest_seqno
So I skip pick sst file which was ingested in function `FindIntraL0Compaction `
## Reason
Here is my bug report: https://github.com/facebook/rocksdb/issues/5913
There are two situations that can cause the check to fail.
### First situation:
- First we ingest five external sst into Rocksdb, and they happened to be ingested in L0. and there had been some data in memtable, which make the smallest sequence number of memtable is less than which of sst that we ingest.
- If there had been one compaction job which compacted sst from L0 to L1, `LevelCompactionPicker` would trigger a `IntraL0Compaction` which would compact this five sst from L0 to L0. We call this sst A, which was merged from five ingested sst.
- Then some data was put into memtable, and memtable was flushed to L0. We called this sst B.
- RocksDB check consistency , and find the `smallest_seqno` of B is less than that of A and crash. Because A was merged from five sst, the smallest sequence number of it was less than the biggest sequece number of itself, so RocksDB could not tell if A was produce by ingested.
### Secondary situaion
- First we have flushed many sst in L0, we call them [s1, s2, s3].
- There is an immutable memtable request to be flushed, but because flush thread is busy, so it has not been picked. we call it m1. And at the moment, one sst is ingested into L0. We call it s4. Because s4 is ingested after m1 became immutable memtable, so it has a larger log sequence number than m1.
- m1 is flushed in L0. because it is small, this flush job finish quickly. we call it s5.
- [s1, s2, s3, s4] are compacted into one sst to L0, by IntraL0Compaction. We call it s6.
- compacted 4@0 files to L0
- When s6 is added into manifest, the corruption happened. because the largest sequence number of s6 is equal to s4, and they are both larger than that of s5. But because s1 is older than m1, so the smallest sequence number of s6 is smaller than that of s5.
- s6.smallest_seqno < s5.smallest_seqno < s5.largest_seqno < s6.largest_seqno
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5958
Differential Revision: D18601316
fbshipit-source-id: 5fe54b3c9af52a2e1400728f565e895cde1c7267
2019-11-19 23:07:49 +00:00
|
|
|
Compaction* PickCompaction(
|
|
|
|
const std::string& /*cf_name*/,
|
|
|
|
const MutableCFOptions& /*mutable_cf_options*/,
|
|
|
|
VersionStorageInfo* /*vstorage*/, LogBuffer* /* log_buffer */,
|
|
|
|
SequenceNumber /* earliest_memtable_seqno */) override {
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
return nullptr;
|
|
|
|
}
|
|
|
|
|
|
|
|
// Always return "nullptr"
|
2018-03-05 21:08:17 +00:00
|
|
|
Compaction* CompactRange(const std::string& /*cf_name*/,
|
|
|
|
const MutableCFOptions& /*mutable_cf_options*/,
|
|
|
|
VersionStorageInfo* /*vstorage*/,
|
|
|
|
int /*input_level*/, int /*output_level*/,
|
2019-04-17 06:29:32 +00:00
|
|
|
const CompactRangeOptions& /*compact_range_options*/,
|
2018-03-05 21:08:17 +00:00
|
|
|
const InternalKey* /*begin*/,
|
|
|
|
const InternalKey* /*end*/,
|
|
|
|
InternalKey** /*compaction_end*/,
|
2019-04-17 06:29:32 +00:00
|
|
|
bool* /*manual_conflict*/,
|
|
|
|
uint64_t /*max_file_num_to_ignore*/) override {
|
CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.
= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h
= EventListener =
* A virtual class that allows users to implement a set of
call-back functions which will be called when specific
events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners
= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
will try to compact those files into the specified level.
= Example =
* Example code can be found in example/compact_files_example.cc, which implements
a simple external compactor using EventListener, GetColumnFamilyMetaData, and
CompactFiles API.
Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test
Reviewers: ljin, igor, rven, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 22:45:18 +00:00
|
|
|
return nullptr;
|
|
|
|
}
|
|
|
|
|
2014-11-13 21:41:43 +00:00
|
|
|
// Always returns false.
|
2016-05-17 20:11:56 +00:00
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virtual bool NeedsCompaction(
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2018-03-05 21:08:17 +00:00
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const VersionStorageInfo* /*vstorage*/) const override {
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2014-11-13 21:41:43 +00:00
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return false;
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}
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2014-05-21 18:43:35 +00:00
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};
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2014-11-26 23:45:11 +00:00
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#endif // !ROCKSDB_LITE
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2014-05-21 18:43:35 +00:00
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2019-05-23 06:38:09 +00:00
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// Attempts to find an intra L0 compaction conforming to the given parameters.
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//
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// @param level_files Metadata for L0 files.
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// @param min_files_to_compact Minimum number of files required to
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// do the compaction.
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// @param max_compact_bytes_per_del_file Maximum average size in bytes per
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// file that is going to get deleted by
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// the compaction.
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// @param max_compaction_bytes Maximum total size in bytes (in terms
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// of compensated file size) for files
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// to be compacted.
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// @param [out] comp_inputs If a compaction was found, will be
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// initialized with corresponding input
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// files. Cannot be nullptr.
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//
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// @return true iff compaction was found.
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Fix corruption with intra-L0 on ingested files (#5958)
Summary:
## Problem Description
Our process was abort when it call `CheckConsistency`. And the information in `stderr` show that "`L0 files seqno 3001491972 3004797440 vs. 3002875611 3004524421` ". Here are the causes of the accident I investigated.
* RocksDB will call `CheckConsistency` whenever `MANIFEST` file is update. It will check sequence number interval of every file, except files which were ingested.
* When one file is ingested into RocksDB, it will be assigned the value of global sequence number, and the minimum and maximum seqno of this file are equal, which are both equal to global sequence number.
* `CheckConsistency` determines whether the file is ingested by whether the smallest and largest seqno of an sstable file are equal.
* If IntraL0Compaction picks one sst which was ingested just now and compacted it into another sst, the `smallest_seqno` of this new file will be smaller than his `largest_seqno`.
* If more than one ingested file was ingested before memtable schedule flush, and they all compact into one new sstable file by `IntraL0Compaction`. The sequence interval of this new file will be included in the interval of the memtable. So `CheckConsistency` will return a `Corruption`.
* If a sstable was ingested after the memtable was schedule to flush, which would assign a larger seqno to it than memtable. Then the file was compacted with other files (these files were all flushed before the memtable) in L0 into one file. This compaction start before the flush job of memtable start, but completed after the flush job finish. So this new file produced by the compaction (we call it s1) would have a larger interval of sequence number than the file produced by flush (we call it s2). **But there was still some data in s1 written into RocksDB before the s2, so it's possible that some data in s2 was cover by old data in s1.** Of course, it would also make a `Corruption` because of overlap of seqno. There is the relationship of the files:
> s1.smallest_seqno < s2.smallest_seqno < s2.largest_seqno < s1.largest_seqno
So I skip pick sst file which was ingested in function `FindIntraL0Compaction `
## Reason
Here is my bug report: https://github.com/facebook/rocksdb/issues/5913
There are two situations that can cause the check to fail.
### First situation:
- First we ingest five external sst into Rocksdb, and they happened to be ingested in L0. and there had been some data in memtable, which make the smallest sequence number of memtable is less than which of sst that we ingest.
- If there had been one compaction job which compacted sst from L0 to L1, `LevelCompactionPicker` would trigger a `IntraL0Compaction` which would compact this five sst from L0 to L0. We call this sst A, which was merged from five ingested sst.
- Then some data was put into memtable, and memtable was flushed to L0. We called this sst B.
- RocksDB check consistency , and find the `smallest_seqno` of B is less than that of A and crash. Because A was merged from five sst, the smallest sequence number of it was less than the biggest sequece number of itself, so RocksDB could not tell if A was produce by ingested.
### Secondary situaion
- First we have flushed many sst in L0, we call them [s1, s2, s3].
- There is an immutable memtable request to be flushed, but because flush thread is busy, so it has not been picked. we call it m1. And at the moment, one sst is ingested into L0. We call it s4. Because s4 is ingested after m1 became immutable memtable, so it has a larger log sequence number than m1.
- m1 is flushed in L0. because it is small, this flush job finish quickly. we call it s5.
- [s1, s2, s3, s4] are compacted into one sst to L0, by IntraL0Compaction. We call it s6.
- compacted 4@0 files to L0
- When s6 is added into manifest, the corruption happened. because the largest sequence number of s6 is equal to s4, and they are both larger than that of s5. But because s1 is older than m1, so the smallest sequence number of s6 is smaller than that of s5.
- s6.smallest_seqno < s5.smallest_seqno < s5.largest_seqno < s6.largest_seqno
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5958
Differential Revision: D18601316
fbshipit-source-id: 5fe54b3c9af52a2e1400728f565e895cde1c7267
2019-11-19 23:07:49 +00:00
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bool FindIntraL0Compaction(
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const std::vector<FileMetaData*>& level_files, size_t min_files_to_compact,
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uint64_t max_compact_bytes_per_del_file, uint64_t max_compaction_bytes,
|
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CompactionInputFiles* comp_inputs,
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|
|
SequenceNumber earliest_mem_seqno = kMaxSequenceNumber);
|
2018-11-30 00:00:39 +00:00
|
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|
|
2015-04-02 18:06:30 +00:00
|
|
|
CompressionType GetCompressionType(const ImmutableCFOptions& ioptions,
|
2016-05-09 22:57:19 +00:00
|
|
|
const VersionStorageInfo* vstorage,
|
2016-05-17 20:11:56 +00:00
|
|
|
const MutableCFOptions& mutable_cf_options,
|
2015-04-02 18:06:30 +00:00
|
|
|
int level, int base_level,
|
|
|
|
const bool enable_compression = true);
|
|
|
|
|
2020-03-31 19:08:41 +00:00
|
|
|
CompressionOptions GetCompressionOptions(
|
|
|
|
const MutableCFOptions& mutable_cf_options,
|
|
|
|
const VersionStorageInfo* vstorage, int level,
|
|
|
|
const bool enable_compression = true);
|
2018-06-28 00:34:07 +00:00
|
|
|
|
2020-02-20 20:07:53 +00:00
|
|
|
} // namespace ROCKSDB_NAMESPACE
|