Commit graph

326 commits

Author SHA1 Message Date
Changyu Bi bceb2dfe6a Introduce minimum compaction debt requirement for parallel compaction (#13054)
Summary:
a small CF can trigger parallel compaction that applies to the entire DB. This is because the bottommost file size of a small CF can be too small compared to l0 files when a l0->lbase compaction happens. We prevent this by requiring some minimum on the compaction debt.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13054

Test Plan: updated unit test.

Reviewed By: hx235

Differential Revision: D63861042

Pulled By: cbi42

fbshipit-source-id: 43bbf327988ef0ef912cd2fc700e3d096a8d2c18
2024-10-04 15:01:54 -07:00
Peter Dillinger a1a102ffce Steps toward deprecating implicit prefix seek, related fixes (#13026)
Summary:
With some new use cases onboarding to prefix extractors/seek/filters, one of the risks is existing iterator code, e.g. for maintenance tasks, being unintentionally subject to prefix seek semantics. This is a longstanding known design flaw with prefix seek, and `prefix_same_as_start` and `auto_prefix_mode` were steps in the direction of making that obsolete. However, we can't just immediately set `total_order_seek` to true by default, because that would impact so much code instantly.

Here we add a new DB option, `prefix_seek_opt_in_only` that basically allows users to transition to the future behavior when they are ready. When set to true, all iterators will be treated as if `total_order_seek=true` and then the only ways to get prefix seek semantics are with `prefix_same_as_start` or `auto_prefix_mode`.

Related fixes / changes:
* Make sure that `prefix_same_as_start` and `auto_prefix_mode` are compatible with (or override) `total_order_seek` (depending on your interpretation).
* Fix a bug in which a new iterator after dynamically changing the prefix extractor might mix different prefix semantics between memtable and SSTs. Both should use the latest extractor semantics, which means iterators ignoring memtable prefix filters with an old extractor. And that means passing the latest prefix extractor to new memtable iterators that might use prefix seek. (Without the fix, the test added for this fails in many ways.)

Suggested follow-up:
* Investigate a FIXME where a MergeIteratorBuilder is created in db_impl.cc. No unit test detects a change in value that should impact correctness.
* Make memtable prefix bloom compatible with `auto_prefix_mode`, which might require involving the memtablereps because we don't know at iterator creation time (only seek time) whether an auto_prefix_mode seek will be a prefix seek.
* Add `prefix_same_as_start` testing to db_stress

Pull Request resolved: https://github.com/facebook/rocksdb/pull/13026

Test Plan:
tests updated, added. Add combination of `total_order_seek=true` and `auto_prefix_mode=true` to stress test. Ran `make blackbox_crash_test` for a long while.

Manually ran tests with `prefix_seek_opt_in_only=true` as default, looking for unexpected issues. I inspected most of the results and migrated many tests to be ready for such a change (but not all).

Reviewed By: ltamasi

Differential Revision: D63147378

Pulled By: pdillinger

fbshipit-source-id: 1f4477b730683d43b4be7e933338583702d3c25e
2024-09-20 15:54:19 -07:00
Yu Zhang 0c6e9c036a Make compaction always use the input version with extra ref protection (#12992)
Summary:
`Compaction` is already creating its own ref for the input Version: 4b1d595306/db/compaction/compaction.cc (L73)

And properly Unref it during destruction:
4b1d595306/db/compaction/compaction.cc (L450)

This PR redirects compaction's access of `cfd->current()` to this input `Version`, to prepare for when a column family's data can be replaced all together, and `cfd->current()` is not safe to access for a compaction job. Because a new `Version` with just some other external files could be installed as `cfd->current()`. The compaction job's expectation of the current `Version` and the corresponding storage info to always have its input files will no longer be guaranteed.

My next follow up is to do a similar thing for flush, also to prepare it for when a column family's data can be replaced. I will make it create its own reference of the current `MemTableListVersion` and use it as input, all flush job's access of memtables will be wired to that input `MemTableListVersion`. Similarly this reference will be unreffed during a flush job's destruction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12992

Test Plan: Existing tests

Reviewed By: pdillinger

Differential Revision: D62212625

Pulled By: jowlyzhang

fbshipit-source-id: 9a781213469cf366857a128d50a702af683a046a
2024-09-06 14:07:33 -07:00
Yu Zhang 81d52bdc1a Fix UDT in memtable only assertions (#12946)
Summary:
Empty memtables can be legitimately created and flushed, for example by error recovery flush attempts:

273b3eadf0/db/db_impl/db_impl_compaction_flush.cc (L2309-L2312)

This check is updated to be considerate of this.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12946

Reviewed By: hx235

Differential Revision: D61492477

Pulled By: jowlyzhang

fbshipit-source-id: 7d16fcaea457948546072f85b3650fd1cc24f9db
2024-08-20 09:19:52 -07:00
Yu Zhang 13c758f986 Change the behavior of manual flush to not retain UDT (#12737)
Summary:
When user-defined timestamps in Memtable only feature is enabled, all scheduled flushes go through a check to see if it's eligible to be rescheduled to retain user-defined timestamps. However when the user makes a manual flush request, their intention is for all the in memory data to be persisted into SST files as soon as possible. These two sides have some conflict of interest, the user can implement some workaround like https://github.com/facebook/rocksdb/issues/12631 to explicitly mark which one takes precedence. The implementation for this can be nuanced since the user needs to be aware of all the scenarios that can trigger a manual flush and handle the concurrency well etc.

In this PR, we updated the default behavior to give manual flush precedence when it's requested. The user-defined timestamps rescheduling mechanism is turned off when a manual flush is requested. Likewise, all error recovery triggered flushes skips the rescheduling mechanism too.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12737

Test Plan: Add unit tests

Reviewed By: ajkr

Differential Revision: D58538246

Pulled By: jowlyzhang

fbshipit-source-id: 0b9b3d1af3e8d882f2d6a2406adda19324ba0694
2024-06-13 13:18:10 -07:00
Changyu Bi 0ee7f8bacb Fix max_read_amp value in crash test (#12701)
Summary:
It should be no less than `level0_file_num_compaction_trigger`(which defaults to 4) when set to a positive value. Otherwise DB open will fail.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12701

Test Plan: crash test not failing DB open due to this option value.

Reviewed By: ajkr

Differential Revision: D57825062

Pulled By: cbi42

fbshipit-source-id: 22d8e12aeceb5cef815157845995a8448552e2d2
2024-05-26 17:26:55 -07:00
Changyu Bi fecb10c2fa Improve universal compaction sorted-run trigger (#12477)
Summary:
Universal compaction currently uses `level0_file_num_compaction_trigger` for two purposes:
1. the trigger for checking if there is any compaction to do, and
2. the limit on the number of sorted runs. RocksDB will do compaction to keep the number of sorted runs no more than the value of this option.

This can make the option inflexible. A value that is too small causes higher write amp: more compactions to reduce the number of sorted runs. A value that is too big delays potential compaction work and causes worse read performance. This PR introduce an option `CompactionOptionsUniversal::max_read_amp` for only the second purpose: to specify
the hard limit on the number of sorted runs.

For backward compatibility, `max_read_amp = -1` by default, which means to fallback to the current behavior.
When `max_read_amp > 0`,`level0_file_num_compaction_trigger` will only serve as a trigger to find potential compaction.
When `max_read_amp = 0`, RocksDB will auto-tune the limit on the number of sorted runs. The estimation is based on DB size, write_buffer_size and size_ratio, so it is adaptive to the size change of the DB. See more in `UniversalCompactionBuilder::PickCompaction()`.
Alternatively, users now can configure `max_read_amp` to a very big value and keep `level0_file_num_compaction_trigger` small. This will allow `size_ratio` and `max_size_amplification_percent` to control the number of sorted runs. This essentially disables compactions with reason kUniversalSortedRunNum.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12477

Test Plan:
* new unit test
* existing unit test for default behavior
* updated crash test with the new option
* benchmark:
  * Create a DB that is roughly 24GB in the last level. When `max_read_amp = 0`, we estimate that the DB needs 9 levels to avoid excessive compactions to reduce the number of sorted runs.
  * We then run fillrandom to ingest another 24GB data to compare write amp.
     * case 1: small level0 trigger: `level0_file_num_compaction_trigger=5, max_read_amp=-1`
       * write-amp: 4.8
     * case 2: auto-tune: `level0_file_num_compaction_trigger=5, max_read_amp=0`
       *  write-amp: 3.6
     * case 3: auto-tune with minimal trigger: `level0_file_num_compaction_trigger=1, max_read_amp=0`
       *  write-amp: 3.8
     * case 4: hard-code a good value for trigger: `level0_file_num_compaction_trigger=9`
       * write-amp: 2.8
```
Case 1:
** Compaction Stats [default] **
Level    Files   Size     Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop Rblob(GB) Wblob(GB)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0      0/0    0.00 KB   1.0      0.0     0.0      0.0      22.6     22.6       0.0   1.0      0.0    163.2    141.94            111.10       108    1.314       0      0       0.0       0.0
 L45      8/0    1.81 GB   0.0     39.6    11.1     28.5      39.3     10.8       0.0   3.5    209.0    207.3    194.25            191.29        43    4.517    348M  2498K       0.0       0.0
 L46     13/0    3.12 GB   0.0     15.3     9.5      5.8      15.0      9.3       0.0   1.6    203.1    199.3     77.13             75.88        16    4.821    134M  2362K       0.0       0.0
 L47     19/0    4.68 GB   0.0     15.4    10.5      4.9      14.7      9.8       0.0   1.4    204.0    194.9     77.38             76.15         8    9.673    135M  5920K       0.0       0.0
 L48     38/0    9.42 GB   0.0     19.6    11.7      7.9      17.3      9.4       0.0   1.5    206.5    182.3     97.15             95.02         4   24.287    172M    20M       0.0       0.0
 L49     91/0   22.70 GB   0.0      0.0     0.0      0.0       0.0      0.0       0.0   0.0      0.0      0.0      0.00              0.00         0    0.000       0      0       0.0       0.0
 Sum    169/0   41.74 GB   0.0     89.9    42.9     47.0     109.0     61.9       0.0   4.8    156.7    189.8    587.85            549.45       179    3.284    791M    31M       0.0       0.0

Case 2:
** Compaction Stats [default] **
Level    Files   Size     Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop Rblob(GB) Wblob(GB)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0      1/0   214.47 MB   1.2      0.0     0.0      0.0      22.6     22.6       0.0   1.0      0.0    164.5    140.81            109.98       108    1.304       0      0       0.0       0.0
 L44      0/0    0.00 KB   0.0      1.3     1.3      0.0       1.2      1.2       0.0   1.0    206.1    204.9      6.24              5.98         3    2.081     11M    51K       0.0       0.0
 L45      4/0   844.36 MB   0.0      7.1     5.4      1.7       7.0      5.4       0.0   1.3    194.6    192.9     37.41             36.00        13    2.878     62M   489K       0.0       0.0
 L46     11/0    2.57 GB   0.0     14.6     9.8      4.8      14.3      9.5       0.0   1.5    193.7    189.8     77.09             73.54        17    4.535    128M  2411K       0.0       0.0
 L47     24/0    5.81 GB   0.0     19.8    12.0      7.8      18.8     11.0       0.0   1.6    191.4    181.1    106.19            101.21         9   11.799    174M  9166K       0.0       0.0
 L48     38/0    9.42 GB   0.0     19.6    11.8      7.9      17.3      9.4       0.0   1.5    197.3    173.6    101.97             97.23         4   25.491    172M    20M       0.0       0.0
 L49     91/0   22.70 GB   0.0      0.0     0.0      0.0       0.0      0.0       0.0   0.0      0.0      0.0      0.00              0.00         0    0.000       0      0       0.0       0.0
 Sum    169/0   41.54 GB   0.0     62.4    40.3     22.1      81.3     59.2       0.0   3.6    136.1    177.2    469.71            423.94       154    3.050    549M    32M       0.0       0.0

Case 3:
** Compaction Stats [default] **
Level    Files   Size     Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop Rblob(GB) Wblob(GB)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0      0/0    0.00 KB   5.0      0.0     0.0      0.0      22.6     22.6       0.0   1.0      0.0    163.8    141.43            111.13       108    1.310       0      0       0.0       0.0
 L44      0/0    0.00 KB   0.0      0.8     0.8      0.0       0.8      0.8       0.0   1.0    201.4    200.2      4.26              4.19         2    2.130   7360K    33K       0.0       0.0
 L45      4/0   844.38 MB   0.0      6.3     5.0      1.2       6.2      5.0       0.0   1.2    202.0    200.3     31.81             31.50        12    2.651     55M   403K       0.0       0.0
 L46      7/0    1.62 GB   0.0     13.3     8.8      4.6      13.1      8.6       0.0   1.5    198.9    195.7     68.72             67.89        17    4.042    117M  1696K       0.0       0.0
 L47     24/0    5.81 GB   0.0     21.7    12.9      8.8      20.6     11.8       0.0   1.6    198.5    188.6    112.04            109.97        12    9.336    191M  9352K       0.0       0.0
 L48     41/0   10.14 GB   0.0     24.8    13.0     11.8      21.9     10.1       0.0   1.7    198.6    175.6    127.88            125.36         6   21.313    218M    25M       0.0       0.0
 L49     91/0   22.70 GB   0.0      0.0     0.0      0.0       0.0      0.0       0.0   0.0      0.0      0.0      0.00              0.00         0    0.000       0      0       0.0       0.0
 Sum    167/0   41.10 GB   0.0     67.0    40.5     26.4      85.4     58.9       0.0   3.8    141.1    179.8    486.13            450.04       157    3.096    589M    36M       0.0       0.0

Case 4:
** Compaction Stats [default] **
Level    Files   Size     Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop Rblob(GB) Wblob(GB)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0      0/0    0.00 KB   0.7      0.0     0.0      0.0      22.6     22.6       0.0   1.0      0.0    158.6    146.02            114.68       108    1.352       0      0       0.0       0.0
 L42      0/0    0.00 KB   0.0      1.7     1.7      0.0       1.7      1.7       0.0   1.0    185.4    184.3      9.25              8.96         4    2.314     14M    67K       0.0       0.0
 L43      0/0    0.00 KB   0.0      2.5     2.5      0.0       2.5      2.5       0.0   1.0    197.8    195.6     13.01             12.65         4    3.253     22M   202K       0.0       0.0
 L44      4/0   844.40 MB   0.0      4.2     4.2      0.0       4.1      4.1       0.0   1.0    188.1    185.1     22.81             21.89         5    4.562     36M   503K       0.0       0.0
 L45     13/0    3.12 GB   0.0      7.5     6.5      1.0       7.2      6.2       0.0   1.1    188.7    181.8     40.69             39.32         5    8.138     65M  2282K       0.0       0.0
 L46     17/0    4.18 GB   0.0      8.3     7.1      1.2       7.9      6.6       0.0   1.1    192.2    181.8     44.23             43.06         4   11.058     73M  3846K       0.0       0.0
 L47     22/0    5.34 GB   0.0      8.9     7.5      1.4       8.2      6.8       0.0   1.1    189.1    174.1     48.12             45.37         3   16.041     78M  6098K       0.0       0.0
 L48     27/0    6.58 GB   0.0      9.2     7.6      1.6       8.2      6.6       0.0   1.1    195.2    172.9     48.52             47.11         2   24.262     81M  9217K       0.0       0.0
 L49     91/0   22.70 GB   0.0      0.0     0.0      0.0       0.0      0.0       0.0   0.0      0.0      0.0      0.00              0.00         0    0.000       0      0       0.0       0.0
 Sum    174/0   42.74 GB   0.0     42.3    37.0      5.3      62.4     57.1       0.0   2.8    116.3    171.3    372.66            333.04       135    2.760    372M    22M       0.0       0.0

setup:
./db_bench --benchmarks=fillseq,compactall,waitforcompaction --num=200000000 --compression_type=none --disable_wal=1 --compaction_style=1 --num_levels=50 --target_file_size_base=268435456 --max_compaction_bytes=6710886400 --level0_file_num_compaction_trigger=10 --write_buffer_size=268435456 --seed 1708494134896523

benchmark:
./db_bench --benchmarks=overwrite,waitforcompaction,stats --num=200000000 --compression_type=none --disable_wal=1 --compaction_style=1 --write_buffer_size=268435456 --level0_file_num_compaction_trigger=5 --target_file_size_base=268435456 --use_existing_db=1 --num_levels=50 --writes=200000000 --universal_max_read_amp=-1 --seed=1716488324800233

```

Reviewed By: ajkr

Differential Revision: D55370922

Pulled By: cbi42

fbshipit-source-id: 9be69979126b840d08e93e7059260e76a878bb2a
2024-05-24 10:10:31 -07:00
Peter Dillinger b515a5db3f Replace ScopedArenaIterator with ScopedArenaPtr<InternalIterator> (#12470)
Summary:
ScopedArenaIterator is not an iterator. It is a pointer wrapper. And we don't need a custom implemented pointer wrapper when std::unique_ptr can be instantiated with what we want.

So this adds ScopedArenaPtr<T> to replace those uses.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12470

Test Plan: CI (including ASAN/UBSAN)

Reviewed By: jowlyzhang

Differential Revision: D55254362

Pulled By: pdillinger

fbshipit-source-id: cc96a0b9840df99aa807f417725e120802c0ae18
2024-03-22 13:40:42 -07:00
Yu Zhang f2546b6623 Support returning write unix time in iterator property (#12428)
Summary:
This PR adds support to return data's approximate unix write time in the iterator property API. The general implementation is:
1) If the entry comes from a SST file, the sequence number to time mapping recorded in that file's table properties will be used to deduce the entry's write time from its sequence number. If no such recording is available, `std::numeric_limits<uint64_t>::max()` is returned to indicate the write time is unknown except if the entry's sequence number is zero, in which case, 0 is returned. This also means that even if `preclude_last_level_data_seconds` and `preserve_internal_time_seconds` can be toggled off between DB reopens, as long as the SST file's table property has the mapping available, the entry's write time can be deduced and returned.

2) If the entry comes from memtable, we will use the DB's sequence number to write time mapping to do similar things. A copy of the DB's seqno to write time mapping is kept in SuperVersion to allow iterators to have lock free access. This also means a new `SuperVersion` is installed each time DB's seqno to time mapping updates, which is originally proposed by Peter in  https://github.com/facebook/rocksdb/issues/11928 . Similarly, if the feature is not enabled, `std::numeric_limits<uint64_t>::max()` is returned to indicate the write time is unknown.

Needed follow up:
1) The write time for `kTypeValuePreferredSeqno` should be special cased, where it's already specified by the user, so we can directly return it.

2) Flush job can be updated to use DB's seqno to time mapping copy in the SuperVersion.

3) Handle the case when `TimedPut` is called with a write time that is `std::numeric_limits<uint64_t>::max()`. We can make it a regular `Put`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12428

Test Plan: Added unit test

Reviewed By: pdillinger

Differential Revision: D54967067

Pulled By: jowlyzhang

fbshipit-source-id: c795b1b7ec142e09e53f2ed3461cf719833cb37a
2024-03-15 15:37:37 -07:00
Peter Dillinger 13ef21c22e default_write_temperature option (#12388)
Summary:
Currently SST files that aren't applicable to last_level_temperature nor file_temperature_age_thresholds are written with temperature kUnknown, which is a little weird and doesn't support CF-based tiering. The default_temperature option only affects how kUnknown is interpreted for stats.

This change adds a new per-CF option default_write_temperature that determines the temperature of new SST files when those other options do not apply.

Also made a change to ignore last_level_temperature with FIFO compaction, because I found that could lead to an infinite loop in compaction.

Needed follow-up: Fix temperature handling with external file ingestion

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12388

Test Plan: unit tests extended appropriately. (Ignore whitespace changes when reviewing.)

Reviewed By: jowlyzhang

Differential Revision: D54266574

Pulled By: pdillinger

fbshipit-source-id: c9ec9a74dbf22be6e986f77f9689d05fea8ef0bb
2024-02-28 14:36:13 -08:00
Yu Zhang e3e8fbb497 Add a separate range classes for internal usage (#12071)
Summary:
Introduce some different range classes `UserKeyRange` and `UserKeyRangePtr` to be used by internal implementation. The `Range` class is used in both public APIs like `DB::GetApproximateSizes`, `DB::GetApproximateMemTableStats`, `DB::GetPropertiesOfTablesInRange` etc and internal implementations like `ColumnFamilyData::RangesOverlapWithMemtables`, `VersionSet::GetPropertiesOfTablesInRange`.

These APIs have different expectations of what keys this range class contain.  Public API users are supposed to populate the range with the user keys without timestamp, in the same way that point lookup and range scan APIs' key input only expect the user key without timestamp. The internal APIs implementation expect a user key whose format is compatible with the user comparator, a.k.a a user key with the timestamp.

This PR contains:
1) introducing counterpart range class `UserKeyRange` `UserKeyRangePtr` for internal implementation while leave the existing `Range` and `RangePtr` class only for public APIs. Internal implementations are updated to use this new class instead.
2) add user-defined timestamp support for `DB::GetPropertiesOfTablesInRange` API and `DeleteFilesInRanges` API.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12071

Test Plan:
existing tests
Added test for `DB::GetPropertiesOfTablesInRange` and `DeleteFilesInRanges` APIs for when user-defined timestamp is enabled.
The change in external_file_ingestion_job doesn't have a user-defined timestamp enabled test case coverage, will add one in a follow up PR that adds file ingestion support for UDT.

Reviewed By: ltamasi

Differential Revision: D53292608

Pulled By: jowlyzhang

fbshipit-source-id: 9a9279e23c640a6d8f8232636501a95aef7638b8
2024-02-06 18:35:36 -08:00
Peter Dillinger 1d6dbfb8b7 Rename IntTblPropCollector -> InternalTblPropColl (#12320)
Summary:
I've always found this name difficult to read, because it sounds like it's for collecting int(eger)
table properties.

I'm fixing this now to set up for a change that I have stubbed out in the public API (table_properties.h):
a new adapter function `TablePropertiesCollector::AsInternal()` that allows RocksDB-provided
TablePropertiesCollectors (such as CompactOnDeletionCollector) to implement the easier-to-upgrade
internal interface while still (superficially) implementing the public interface. In addition to added flexibility,
this should be a performance improvement as the adapter class UserKeyTablePropertiesCollector can be
avoided for such cases where a RocksDB-provided collector is used (AsInternal() returns non-nullptr).

table_properties.h is the only file with changes that aren't simple find-replace renaming.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12320

Test Plan: existing tests, CI

Reviewed By: ajkr

Differential Revision: D53336945

Pulled By: pdillinger

fbshipit-source-id: 02535bcb30bbfb00e29e8478af62e5dad50a63b8
2024-02-02 14:14:43 -08:00
Yu Zhang d11584e42e Be consistent in key range overlap check (#12315)
Summary:
We should be consistent in how we check key range overlap in memtables and in sst files. While all the sst file key range overlap check compares the user key without timestamp, for example:
377eee77f8/db/version_set.cc (L129-L130)

This key range overlap check for memtable is comparing the whole user key. Currently it happen to achieve the same effect because this function is only called by `ExternalSstFileIngestionJob` and `DBImpl::CompactRange`, which takes a user key without timestamp as the range end, pad a max or min timestamp to it depending on whether the end is exclusive. So use `Compartor::Compare` here is working too, but we should update it to `Comparator::CompareWithoutTimestamp` to be consistent with all the other file key range overlapping check functions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12315

Test Plan: existing tests

Reviewed By: ltamasi

Differential Revision: D53273456

Pulled By: jowlyzhang

fbshipit-source-id: c094ae1f0c195d52542124c4fb03fdca14241e85
2024-01-31 11:12:52 -08:00
Andrew Kryczka aacf60dda2 Speedup based on number of files marked for compaction (#12306)
Summary:
RocksDB self throttles per-DB compaction parallelism until it detects compaction pressure. This PR adds pressure detection based on the number of files marked for compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12306

Reviewed By: cbi42

Differential Revision: D53200559

Pulled By: ajkr

fbshipit-source-id: 63402ee336881a4539204d255960f04338ab7a0e
2024-01-29 17:29:04 -08:00
Andrew Kryczka 2dda7a0dd2 Detect compaction pressure at lower debt ratios (#12236)
Summary:
This PR significantly reduces the compaction pressure threshold introduced in https://github.com/facebook/rocksdb/issues/12130 by a factor of 64x. The original number was too high to trigger in scenarios where compaction parallelism was needed.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12236

Reviewed By: cbi42

Differential Revision: D52765685

Pulled By: ajkr

fbshipit-source-id: 8298e966933b485de24f63165a00e672cb9db6c4
2024-01-15 22:41:18 -08:00
leipeng d411fc4dd6 column_family.cc: SanitizeOptions(dbo, cfo): WARN msg: add missing spaces (#12193)
Summary:
Fix for multi line strings missing spaces.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12193

Reviewed By: cbi42

Differential Revision: D52457430

Pulled By: ajkr

fbshipit-source-id: 4ca75a14e61c09819e5d821da6137f4536e9e76e
2024-01-02 11:18:11 -08:00
Hui Xiao 06e593376c Group SST write in flush, compaction and db open with new stats (#11910)
Summary:
## Context/Summary
Similar to https://github.com/facebook/rocksdb/pull/11288, https://github.com/facebook/rocksdb/pull/11444, categorizing SST/blob file write according to different io activities allows more insight into the activity.

For that, this PR does the following:
- Tag different write IOs by passing down and converting WriteOptions to IOOptions
- Add new SST_WRITE_MICROS histogram in WritableFileWriter::Append() and breakdown FILE_WRITE_{FLUSH|COMPACTION|DB_OPEN}_MICROS

Some related code refactory to make implementation cleaner:
- Blob stats
   - Replace high-level write measurement with low-level WritableFileWriter::Append() measurement for BLOB_DB_BLOB_FILE_WRITE_MICROS. This is to make FILE_WRITE_{FLUSH|COMPACTION|DB_OPEN}_MICROS  include blob file. As a consequence, this introduces some behavioral changes on it, see HISTORY and db bench test plan below for more info.
   - Fix bugs where BLOB_DB_BLOB_FILE_SYNCED/BLOB_DB_BLOB_FILE_BYTES_WRITTEN include file failed to sync and bytes failed to write.
- Refactor WriteOptions constructor for easier construction with io_activity and rate_limiter_priority
- Refactor DBImpl::~DBImpl()/BlobDBImpl::Close() to bypass thread op verification
- Build table
   - TableBuilderOptions now includes Read/WriteOpitons so BuildTable() do not need to take these two variables
   - Replace the io_priority passed into BuildTable() with TableBuilderOptions::WriteOpitons::rate_limiter_priority. Similar for BlobFileBuilder.
This parameter is used for dynamically changing file io priority for flush, see  https://github.com/facebook/rocksdb/pull/9988?fbclid=IwAR1DtKel6c-bRJAdesGo0jsbztRtciByNlvokbxkV6h_L-AE9MACzqRTT5s for more
   - Update ThreadStatus::FLUSH_BYTES_WRITTEN to use io_activity to track flush IO in flush job and db open instead of io_priority

## Test
### db bench

Flush
```
./db_bench --statistics=1 --benchmarks=fillseq --num=100000 --write_buffer_size=100

rocksdb.sst.write.micros P50 : 1.830863 P95 : 4.094720 P99 : 6.578947 P100 : 26.000000 COUNT : 7875 SUM : 20377
rocksdb.file.write.flush.micros P50 : 1.830863 P95 : 4.094720 P99 : 6.578947 P100 : 26.000000 COUNT : 7875 SUM : 20377
rocksdb.file.write.compaction.micros P50 : 0.000000 P95 : 0.000000 P99 : 0.000000 P100 : 0.000000 COUNT : 0 SUM : 0
rocksdb.file.write.db.open.micros P50 : 0.000000 P95 : 0.000000 P99 : 0.000000 P100 : 0.000000 COUNT : 0 SUM : 0
```

compaction, db oopen
```
Setup: ./db_bench --statistics=1 --benchmarks=fillseq --num=10000 --disable_auto_compactions=1 -write_buffer_size=100 --db=../db_bench

Run:./db_bench --statistics=1 --benchmarks=compact  --db=../db_bench --use_existing_db=1

rocksdb.sst.write.micros P50 : 2.675325 P95 : 9.578788 P99 : 18.780000 P100 : 314.000000 COUNT : 638 SUM : 3279
rocksdb.file.write.flush.micros P50 : 0.000000 P95 : 0.000000 P99 : 0.000000 P100 : 0.000000 COUNT : 0 SUM : 0
rocksdb.file.write.compaction.micros P50 : 2.757353 P95 : 9.610687 P99 : 19.316667 P100 : 314.000000 COUNT : 615 SUM : 3213
rocksdb.file.write.db.open.micros P50 : 2.055556 P95 : 3.925000 P99 : 9.000000 P100 : 9.000000 COUNT : 23 SUM : 66
```

blob stats - just to make sure they aren't broken by this PR
```
Integrated Blob DB

Setup: ./db_bench --enable_blob_files=1 --statistics=1 --benchmarks=fillseq --num=10000 --disable_auto_compactions=1 -write_buffer_size=100 --db=../db_bench

Run:./db_bench --enable_blob_files=1 --statistics=1 --benchmarks=compact  --db=../db_bench --use_existing_db=1

pre-PR:
rocksdb.blobdb.blob.file.write.micros P50 : 7.298246 P95 : 9.771930 P99 : 9.991813 P100 : 16.000000 COUNT : 235 SUM : 1600
rocksdb.blobdb.blob.file.synced COUNT : 1
rocksdb.blobdb.blob.file.bytes.written COUNT : 34842

post-PR:
rocksdb.blobdb.blob.file.write.micros P50 : 2.000000 P95 : 2.829360 P99 : 2.993779 P100 : 9.000000 COUNT : 707 SUM : 1614
- COUNT is higher and values are smaller as it includes header and footer write
- COUNT is 3X higher due to each Append() count as one post-PR, while in pre-PR, 3 Append()s counts as one. See https://github.com/facebook/rocksdb/pull/11910/files#diff-32b811c0a1c000768cfb2532052b44dc0b3bf82253f3eab078e15ff201a0dabfL157-L164

rocksdb.blobdb.blob.file.synced COUNT : 1 (stay the same)
rocksdb.blobdb.blob.file.bytes.written COUNT : 34842 (stay the same)
```

```
Stacked Blob DB

Run: ./db_bench --use_blob_db=1 --statistics=1 --benchmarks=fillseq --num=10000 --disable_auto_compactions=1 -write_buffer_size=100 --db=../db_bench

pre-PR:
rocksdb.blobdb.blob.file.write.micros P50 : 12.808042 P95 : 19.674497 P99 : 28.539683 P100 : 51.000000 COUNT : 10000 SUM : 140876
rocksdb.blobdb.blob.file.synced COUNT : 8
rocksdb.blobdb.blob.file.bytes.written COUNT : 1043445

post-PR:
rocksdb.blobdb.blob.file.write.micros P50 : 1.657370 P95 : 2.952175 P99 : 3.877519 P100 : 24.000000 COUNT : 30001 SUM : 67924
- COUNT is higher and values are smaller as it includes header and footer write
- COUNT is 3X higher due to each Append() count as one post-PR, while in pre-PR, 3 Append()s counts as one. See https://github.com/facebook/rocksdb/pull/11910/files#diff-32b811c0a1c000768cfb2532052b44dc0b3bf82253f3eab078e15ff201a0dabfL157-L164

rocksdb.blobdb.blob.file.synced COUNT : 8 (stay the same)
rocksdb.blobdb.blob.file.bytes.written COUNT : 1043445 (stay the same)
```

###  Rehearsal CI stress test
Trigger 3 full runs of all our CI stress tests

###  Performance

Flush
```
TEST_TMPDIR=/dev/shm ./db_basic_bench_pre_pr --benchmark_filter=ManualFlush/key_num:524288/per_key_size:256 --benchmark_repetitions=1000
-- default: 1 thread is used to run benchmark; enable_statistics = true

Pre-pr: avg 507515519.3 ns
497686074,499444327,500862543,501389862,502994471,503744435,504142123,504224056,505724198,506610393,506837742,506955122,507695561,507929036,508307733,508312691,508999120,509963561,510142147,510698091,510743096,510769317,510957074,511053311,511371367,511409911,511432960,511642385,511691964,511730908,

Post-pr: avg 511971266.5 ns, regressed 0.88%
502744835,506502498,507735420,507929724,508313335,509548582,509994942,510107257,510715603,511046955,511352639,511458478,512117521,512317380,512766303,512972652,513059586,513804934,513808980,514059409,514187369,514389494,514447762,514616464,514622882,514641763,514666265,514716377,514990179,515502408,
```

Compaction
```
TEST_TMPDIR=/dev/shm ./db_basic_bench_{pre|post}_pr --benchmark_filter=ManualCompaction/comp_style:0/max_data:134217728/per_key_size:256/enable_statistics:1  --benchmark_repetitions=1000
-- default: 1 thread is used to run benchmark

Pre-pr: avg 495346098.30 ns
492118301,493203526,494201411,494336607,495269217,495404950,496402598,497012157,497358370,498153846

Post-pr: avg 504528077.20, regressed 1.85%. "ManualCompaction" include flush so the isolated regression for compaction should be around 1.85-0.88 = 0.97%
502465338,502485945,502541789,502909283,503438601,504143885,506113087,506629423,507160414,507393007
```

Put with WAL (in case passing WriteOptions slows down this path even without collecting SST write stats)
```
TEST_TMPDIR=/dev/shm ./db_basic_bench_pre_pr --benchmark_filter=DBPut/comp_style:0/max_data:107374182400/per_key_size:256/enable_statistics:1/wal:1  --benchmark_repetitions=1000
-- default: 1 thread is used to run benchmark

Pre-pr: avg 3848.10 ns
3814,3838,3839,3848,3854,3854,3854,3860,3860,3860

Post-pr: avg 3874.20 ns, regressed 0.68%
3863,3867,3871,3874,3875,3877,3877,3877,3880,3881
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11910

Reviewed By: ajkr

Differential Revision: D49788060

Pulled By: hx235

fbshipit-source-id: 79e73699cda5be3b66461687e5147c2484fc5eff
2023-12-29 15:29:23 -08:00
Andrew Kryczka 4fefe1fed9 Downgrade warning for dynamic leveling with non-leveled compaction (#12186)
Summary:
Now that `level_compaction_dynamic_level_bytes`'s default value is true, users who do not touch that setting and use non-leveled compaction will also see this log message. It can be info level rather than warning since, in the case mentioned, there is nothing the user needs to be warned about.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12186

Reviewed By: cbi42

Differential Revision: D52422499

Pulled By: ajkr

fbshipit-source-id: 8dbfcd102aab671b881ba047fb4a0a555b3e0a78
2023-12-26 15:13:42 -08:00
Andrew Kryczka d8e47620d7 Speedup based on pending compaction bytes relative to data size (#12130)
Summary:
RocksDB self throttles per-DB compaction parallelism until it detects compaction pressure. The pressure detection based on pending compaction bytes was only comparing against the slowdown trigger (`soft_pending_compaction_bytes_limit`). Online services tend to set that extremely high to avoid stalling at all costs. Perhaps they should have set it to zero, but we never documented that zero disables stalling so I have been telling everyone to increase it for years.

This PR adds pressure detection based on pending compaction bytes relative to the size of bottommost data. The size of bottommost data should be fairly stable and proportional to the logical data size

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12130

Reviewed By: hx235

Differential Revision: D52000746

Pulled By: ajkr

fbshipit-source-id: 7e1fd170901a74c2d4a69266285e3edf6e7631c7
2023-12-13 10:37:27 -08:00
Levi Tamasi 51d7e6a49e Clean up WriteBatchWithIndexInternal a bit (#11930)
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11930

The patch cleans up and refactors the logic in/around `WriteBatchWithIndexInternal` a bit as groundwork for further changes. Specifically, the class is turned back into a stateless collection of static helpers (which is the way it was before PR 6851). Note that there were two apparent reasons for introducing this instance state in PR 6851: a) encapsulating `MergeContext` and b) resolving objects like `Logger` and `Statistics` based on a variety of handles. However, neither reason seems justified at this point. Regarding a), the `MultiGetFromBatchAndDB` logic passes in its own `MergeContext` objects via a second set of methods that do not use the member `MergeContext`. As for b), `Logger` and friends are only needed for Merge, which is only supported if a column family handle is provided; in turn, the column family handle enables us to resolve all the necessary objects without the need for any other handles like `DB` or `DBOptions`. In addition to the above, the patch changes the type of `BaseDeltaIterator::merge_result_` to `std::string` from `PinnableSlice` (since no pinning is ever done) and makes some other small code quality improvements.

Reviewed By: jaykorean

Differential Revision: D50038302

fbshipit-source-id: 5f34abe2e808bdaea0f3a8033b5764ebd446b85d
2023-10-09 15:25:35 -07:00
Hui Xiao 089070cb36 Expose more info about input files in CompactionFilter::Context (#11857)
Summary:
**Context:**
As requested, lowest level as well as a map from input file to its table properties among all input files used in table creation  (if any) are exposed in `CompactionFilter::Context`.

**Summary:**
This PR contains two commits:
(1) [Refactory](0012777f0e) to make resonating/using what is in `Compaction:: table_properties_` easier
- Separate `Compaction:: table_properties_` into `Compaction:: input_table_properties_` and `Compaction:: output_table_properties_`
- Separate the "set input table properties" logic into `Compaction:: SetInputTableProperties()`) from `Compaction:: GetInputTableProperties`
- Call `Compaction:: SetInputTableProperties()` as soon as possible, which is right after `Compaction::SetInputVersion()`. Bundle these two functions into one `Compaction::FinalizeInputInfo()` to minimize missing one or the other

(2) [Expose more info about input files:](6093e7dfba) `CompactionFilter::Context::input_start_level/input_table_properties`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11857

Test Plan:
- Modify existing UT `
TEST_F(DBTestCompactionFilter, CompactionFilterContextManual)` to cover new logics

Reviewed By: ajkr

Differential Revision: D49402540

Pulled By: hx235

fbshipit-source-id: 469fff50fa0e5964ffa5ea8db0743f61438ea392
2023-09-20 13:34:39 -07:00
Changyu Bi 6997a06c63 Invalidate threadlocal SV before incrementing super_version_number_ (#11848)
Summary:
CI has been hitting assertion error like
```
https://github.com/facebook/rocksdb/issues/8  0x00007fafd9294fd6 in __GI___assert_fail (assertion=assertion@entry=0x7fafda270300 "!*memtable_range_tombstone_iter_ || sv_number_ != cfd_->GetSuperVersionNumber()", file=file@entry=0x7fafda270350 "db/arena_wrapped_db_iter.cc", line=line@entry=124, function=function@entry=0x7fafda270288 "virtual rocksdb::Status rocksdb::ArenaWrappedDBIter::Refresh(const rocksdb::Snapshot*)") at assert.c:101
```

This is due to
* Iterator::Refresh() passing in `cur_sv_number` instead of `sv->version_number` here: 1c6faf3587/db/arena_wrapped_db_iter.cc (L94-L96)

* `super_version_number_` can be incremented before thread local SV is installed: https://github.com/facebook/rocksdb/blob/main/db/column_family.cc#L1287-L1306

* The optimization in https://github.com/facebook/rocksdb/issues/11452 removed the check for SV number, such that `cur_sv_number > sv.version_number` is possible in the following code.
```
uint64_t cur_sv_number = cfd_->GetSuperVersionNumber();
SuperVersion* sv = cfd_->GetReferencedSuperVersion(db_impl_);
```

Not sure why assertion only started failing after https://github.com/facebook/rocksdb/issues/10594, maybe it's because Refresh() is called more often in stress test.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11848

Test Plan:
* This repros hits the assertion pretty consistently before this change:
```
./db_stress --acquire_snapshot_one_in=10000 --adaptive_readahead=1 --allow_data_in_errors=True --async_io=0 --atomic_flush=1 --auto_readahead_size=1 --avoid_flush_during_recovery=0 --avoid_unnecessary_blocking_io=1 --backup_one_in=0 --block_size=16384 --bloom_bits=0.7161318870366848 --cache_index_and_filter_blocks=0 --cache_size=8388608 --charge_table_reader=0 --checkpoint_one_in=1000000 --checksum_type=kxxHash --clear_column_family_one_in=0 --compact_files_one_in=1000000 --compact_range_one_in=1000000 --compaction_pri=3 --compaction_readahead_size=0 --compaction_ttl=0 --compression_checksum=0 --compression_max_dict_buffer_bytes=0 --compression_max_dict_bytes=0 --compression_parallel_threads=1 --compression_type=zlib --compression_use_zstd_dict_trainer=0 --compression_zstd_max_train_bytes=0 --continuous_verification_interval=0 --data_block_index_type=0 --db_write_buffer_size=8388608 --delpercent=4 --delrangepercent=1 --destroy_db_initially=1 --detect_filter_construct_corruption=0 --disable_wal=1 --enable_compaction_filter=0 --enable_pipelined_write=0 --enable_thread_tracking=1 --fail_if_options_file_error=0 --fifo_allow_compaction=1 --file_checksum_impl=none --flush_one_in=1000000 --format_version=5 --get_current_wal_file_one_in=0 --get_live_files_one_in=1000000 --get_property_one_in=1000000 --get_sorted_wal_files_one_in=0 --index_block_restart_interval=14 --index_type=2 --ingest_external_file_one_in=0 --initial_auto_readahead_size=524288 --iterpercent=30 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=1 --lock_wal_one_in=1000000 --long_running_snapshots=1 --manual_wal_flush_one_in=0 --mark_for_compaction_one_file_in=0 --max_auto_readahead_size=524288 --max_background_compactions=20 --max_bytes_for_level_base=10485760 --max_key=2500000 --max_key_len=3 --max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=16777216 --max_write_buffer_number=3 --max_write_buffer_size_to_maintain=1048576 --memtable_max_range_deletions=0 --memtable_prefix_bloom_size_ratio=0.5 --memtable_protection_bytes_per_key=0 --memtable_whole_key_filtering=1 --memtablerep=skip_list --min_write_buffer_number_to_merge=1 --mmap_read=1 --mock_direct_io=False --nooverwritepercent=1 --num_file_reads_for_auto_readahead=1 --open_files=500000 --ops_per_thread=100000000 --optimize_filters_for_memory=1 --paranoid_file_checks=0 --partition_filters=0 --partition_pinning=3 --pause_background_one_in=1000000 --periodic_compaction_seconds=0 --prefix_size=-1 --prefixpercent=0 --prepopulate_block_cache=0 --preserve_internal_time_seconds=0 --progress_reports=0 --read_fault_one_in=32 --readahead_size=16384 --readpercent=30 --recycle_log_file_num=1 --reopen=0 --ribbon_starting_level=999 --secondary_cache_fault_one_in=0 --secondary_cache_uri= --set_options_one_in=10000 --snapshot_hold_ops=100000 --sst_file_manager_bytes_per_sec=104857600 --sst_file_manager_bytes_per_truncate=0 --stats_dump_period_sec=600 --subcompactions=1 --sync=0 --sync_fault_injection=1 --target_file_size_base=2097152 --target_file_size_multiplier=2 --test_batches_snapshots=0 --test_cf_consistency=1 --top_level_index_pinning=3 --unpartitioned_pinning=3 --use_direct_io_for_flush_and_compaction=0 --use_direct_reads=0 --use_full_merge_v1=0 --use_get_entity=0 --use_merge=0 --use_multi_get_entity=0 --use_multiget=1 --use_put_entity_one_in=0 --user_timestamp_size=0 --value_size_mult=32 --verification_only=0 --verify_checksum=1 --verify_checksum_one_in=1000000 --verify_db_one_in=100000 --verify_file_checksums_one_in=0 --verify_sst_unique_id_in_manifest=1 --wal_bytes_per_sync=0 --wal_compression=none --write_buffer_size=1048576 --write_dbid_to_manifest=1 --write_fault_one_in=0 --writepercent=35 --use_io_uring=0 --db=/tmp/rocksdb_crashtest_blackboxnf3pyv_0 --expected_values_dir=/tmp/rocksdb_crashtest_expected_6opy9nqg
```

Reviewed By: ajkr

Differential Revision: D49344066

Pulled By: cbi42

fbshipit-source-id: d5373ddb48d933acb42a5dd8fae3f3019b0241e5
2023-09-18 09:37:40 -07:00
Yu Zhang 39a4ff2cab Track full_history_ts_low per SuperVersion (#11784)
Summary:
As discussed in https://github.com/facebook/rocksdb/issues/11730 , this PR tracks the effective `full_history_ts_low` per SuperVersion and update existing sanity checks for `ReadOptions.timestamp >= full_history_ts_low` to use this per SuperVersion `full_history_ts_low` instead. This also means the check is moved to happen after acquiring SuperVersion.

There are two motivations for this: 1) Each time `full_history_ts_low` really come into effect to collapse history, a new SuperVersion is always installed, because it would involve either a Flush or Compaction, both of which change the LSM tree shape. We can take advantage of this to ensure that as long as this sanity check is passed, even if `full_history_ts_low` can be concurrently increased and collapse some history above the requested `ReadOptions.timestamp`, a read request won’t have visibility to that part of history through this SuperVersion that it already acquired.  2) the existing sanity check uses `ColumnFamilyData::GetFullHistoryTsLow` without locking the db mutex, which is the mutex all `IncreaseFullHistoryTsLow` operation is using when mutating this field. So there is a race condition. This also solve the race condition on the read path.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11784

Test Plan:
`make all check`

// Checks success scenario really provide the read consistency attribute as mentioned above.
`./db_with_timestamp_basic_test --gtest_filter=*FullHistoryTsLowSanityCheckPassReadIsConsistent*`

// Checks failure scenario cleans up SuperVersion properly.
`./db_with_timestamp_basic_test --gtest_filter=*FullHistoryTsLowSanityCheckFail*`
`./db_secondary_test --gtest_filter=*FullHistoryTsLowSanityCheckFail*`
`./db_readonly_with_timestamp_test --gtest_filter=*FullHistoryTsLowSanitchCheckFail*`

Reviewed By: ltamasi

Differential Revision: D48894795

Pulled By: jowlyzhang

fbshipit-source-id: 1f801fe8e1bc8e63ca76c03cbdbd0974e5ff5bf6
2023-09-13 16:34:18 -07:00
Yu Zhang ecbeb305a0 Removing some checks for UDT in memtable only feature (#11732)
Summary:
The user-defined timestamps feature only enforces that for the same key, user-defined timestamps should be non-decreasing. For the user-defined timestamps in memtable only feature, during flush, we check the user-defined timestamps in each memtable to examine if the data is considered expired with regard to `full_history_ts_low`. In this process, it's assuming that a newer memtable should not have smaller user-defined timestamps than an older memtable. This check however is enforcing ordering of user-defined timestamps across keys, as apposed to the vanilla UDT feature, that only enforce ordering of user-defined timestamps for the same key.

This more strict user-defined timestamp ordering requirement could be an issue for secondary instances where commits can be out of order. And after thinking more about it, this requirement is really an overkill to keep the invariants of `full_history_ts_low` which are:

1) users cannot read below `full_history_ts_low`
2) users cannot write at or below `full_history_ts_low`
3) `full_history_ts_low` can only be increasing

As long as RocksDB enforces these 3 checks, we can prohibit inconsistent read that returns a different value. And these three checks are covered in existing APIs.

So this PR removes the extra checks in the UDT in memtable only feature that requires user-defined timestamps to be non decreasing across keys.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11732

Reviewed By: ltamasi

Differential Revision: D48541466

Pulled By: jowlyzhang

fbshipit-source-id: 95453c6e391cbd511c0feab05f0b11c312d17186
2023-08-29 16:51:48 -07:00
Yu Zhang 4ea7b796b7 Respect cutoff timestamp during flush (#11599)
Summary:
Make flush respect the cutoff timestamp `full_history_ts_low` as much as possible for the user-defined timestamps in Memtables only feature. We achieve this by not proceeding with the actual flushing but instead reschedule the same `FlushRequest` so a follow up flush job can continue with the check after some interval.

This approach doesn't work well for atomic flush, so this feature currently is not supported in combination with atomic flush. Furthermore, this approach also requires a customized method to get the next immediately bigger user-defined timestamp. So currently it's limited to comparator that use uint64_t as the user-defined timestamp format. This support can be extended when we add such a customized method to `AdvancedColumnFamilyOptions`.

For non atomic flush request, at any single time, a column family can only have as many as one FlushRequest for it in the `flush_queue_`. There is deduplication done at `FlushRequest` enqueueing(`SchedulePendingFlush`) and dequeueing time (`PopFirstFromFlushQueue`). We hold the db mutex between when a `FlushRequest` is popped from the queue and the same FlushRequest get rescheduled, so no other `FlushRequest` with a higher `max_memtable_id` can be added to the `flush_queue_` blocking us from re-enqueueing the same `FlushRequest`.

Flush is continued nevertheless if there is risk of entering write stall mode had the flush being postponed, e.g. due to accumulation of write buffers, exceeding the `max_write_buffer_number` setting. When this happens, the newest user-defined timestamp in the involved Memtables need to be tracked and we use it to increase the `full_history_ts_low`, which is an inclusive cutoff timestamp for which RocksDB promises to keep all user-defined timestamps equal to and newer than it.

Tet plan:
```
./column_family_test --gtest_filter="*RetainUDT*"
./memtable_list_test --gtest_filter="*WithTimestamp*"
./flush_job_test --gtest_filter="*WithTimestamp*"
```

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11599

Reviewed By: ajkr

Differential Revision: D47561586

Pulled By: jowlyzhang

fbshipit-source-id: 9400445f983dd6eac489e9dd0fb5d9b99637fe89
2023-07-26 16:25:06 -07:00
Changyu Bi 5c2a063c49 Clarify usage for options ttl and periodic_compaction_seconds for universal compaction (#11552)
Summary:
this is stacked on https://github.com/facebook/rocksdb/issues/11550 to further clarify usage of these two options for universal compaction. Similar to FIFO, the two options have the same meaning for universal compaction, which can be confusing to use. For example, for universal compaction, dynamically changing the value of `ttl` has no impact on periodic compactions. Users should dynamically change `periodic_compaction_seconds` instead. From feature matrix (https://fburl.com/daiquery/5s647hwh), there are instances where users set `ttl` to non-zero value and `periodic_compaction_seconds` to 0. For backward compatibility reason, instead of deprecating `ttl`, comments are added to mention that `periodic_compaction_seconds` are preferred. In `SanitizeOptions()`, we update the value of `periodic_compaction_seconds` to take into account value of `ttl`. The logic is documented in relevant option comment.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11552

Test Plan: * updated existing unit test `DBTestUniversalCompaction2.PeriodicCompactionDefault`

Reviewed By: ajkr

Differential Revision: D47381434

Pulled By: cbi42

fbshipit-source-id: bc41f29f77318bae9a96be84dd89bf5617c7fd57
2023-07-26 11:31:54 -07:00
Changyu Bi df082c8d1d Deprecate option periodic_compaction_seconds for FIFO compaction (#11550)
Summary:
both options `ttl` and `periodic_compaction_seconds` have the same meaning for FIFO compaction, which is redundant and can be confusing to use. For example, setting TTL to 0 does not disable TTL: user needs to also set periodic_compaction_seconds to 0. Another example is that dynamically setting `periodic_compaction_seconds` (surprisingly) has no effect on TTL compaction. This is because FIFO compaction picker internally only looks at value of `ttl`. The value of `ttl` is in `SanitizeOptions()` which take into account the value of `periodic_compaction_seconds`, but dynamically setting an option does not invoke this method.

This PR clarifies the usage of both options for FIFO compaction: only `ttl` should be used, `periodic_compaction_seconds` will not have any effect on FIFO compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11550

Test Plan:
- updated existing unit test `DBOptionsTest.SanitizeFIFOPeriodicCompaction`
- checked existing values of both options in feature matrix: https://fburl.com/daiquery/xxd0gs9w. All current uses cases either have `periodic_compaction_seconds = 0` or have `periodic_compaction_seconds > ttl`, so should not cause change of behavior.

Reviewed By: ajkr

Differential Revision: D46902959

Pulled By: cbi42

fbshipit-source-id: a9ede235b276783b4906aaec443551fa62ceff4c
2023-07-05 14:40:45 -07:00
Yu Zhang 56ca9e3106 Logging timestamp size record in WAL and use it during recovery (#11471)
Summary:
Start logging the timestamp size record in WAL and use the record during recovery.  Currently, user comparator cannot be different from what was used to create a column family, so the timestamp size record is just used to confirm it's consistent with the timestamp size the running user comparator indicates.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11471

Test Plan:
```
make all check
./db_secondary_test
./db_wal_test --gtest_filter="*WithTimestamp*"
./repair_test --gtest_filter="*WithTimestamp*"
```

Reviewed By: ltamasi

Differential Revision: D46236769

Pulled By: jowlyzhang

fbshipit-source-id: f6c60b5c8defdb05021c63df302ccc0be1275ad0
2023-05-30 19:32:00 -07:00
rogertyang 28bf7ba77d remove unnecessary code in super version getter (#11452)
Summary:
Do not bother comparing the version of the local super version handle with the global one.

An inequality comparison result indicates nothing but a spurious obsoleteness. It only happens when the writer has increased the `ColumnFamilyData::super_version_number_`(5fc57eec2b/db/column_family.cc (L1309)) but has not yet called `ResetThreadLocalSuperVersions()`(5fc57eec2b/db/column_family.cc (L1328)) at the time when a reader reads the local handle(`void* ptr = local_sv_->Swap(SuperVersion::kSVInUse);`). In other words, the existence of a local handle is a sufficent evidence of its fressness.

With this PR, we save one or even two atomic instructions when getting a handle of super version.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11452

Reviewed By: ajkr

Differential Revision: D46059317

Pulled By: cbi42

fbshipit-source-id: 68b4b1ca8a9929a4aa470105c37a09e0625b014d
2023-05-23 12:16:24 -07:00
Changyu Bi 8827cd0618 Support compacting files to different temperatures in FIFO compaction (#11428)
Summary:
- Add a new option `CompactionOptionsFIFO::file_temperature_age_thresholds` that allows user to specify age thresholds for compacting files to different temperatures. File temperature can be used to store files in different storage media. The new options allows specifying multiple temperature-age pairs. The option uses struct for a temperature-age pair to use the existing parsing functionality to make the option dynamically settable.
- Deprecate the old option `age_for_warm` that was added for a similar purpose.
- Compaction score calculation logic is updated to check if a file needs to be compacted to change its temperature.
- Some refactoring is done in `FIFOCompactionPicker::PickTemperatureChangeCompaction`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11428

Test Plan: adapted unit tests that were for `age_for_warm` to this new option.

Reviewed By: ajkr

Differential Revision: D45611412

Pulled By: cbi42

fbshipit-source-id: 2dc384841f61cc04abb9681e31aa2de0f0b06106
2023-05-11 16:40:59 -07:00
Changyu Bi 62fc15f009 Block per key-value checksum (#11287)
Summary:
add option `block_protection_bytes_per_key` and implementation for block per key-value checksum. The main changes are
1. checksum construction and verification in block.cc/h
2. pass the option `block_protection_bytes_per_key` around (mainly for methods defined in table_cache.h)
3. unit tests/crash test updates

Tests:
* Added unit tests
* Crash test: `python3 tools/db_crashtest.py blackbox --simple --block_protection_bytes_per_key=1 --write_buffer_size=1048576`

Follow up (maybe as a separate PR): make sure corruption status returned from BlockIters are correctly handled.

Performance:
Turning on block per KV protection has a non-trivial negative impact on read performance and costs additional memory.
For memory, each block includes additional 24 bytes for checksum-related states beside checksum itself. For CPU, I set up a DB of size ~1.2GB with 5M keys (32 bytes key and 200 bytes value) which compacts to ~5 SST files (target file size 256 MB) in L6 without compression. I tested readrandom performance with various block cache size (to mimic various cache hit rates):

```
SETUP
make OPTIMIZE_LEVEL="-O3" USE_LTO=1 DEBUG_LEVEL=0 -j32 db_bench
./db_bench -benchmarks=fillseq,compact0,waitforcompaction,compact,waitforcompaction -write_buffer_size=33554432 -level_compaction_dynamic_level_bytes=true -max_background_jobs=8 -target_file_size_base=268435456 --num=5000000 --key_size=32 --value_size=200 --compression_type=none

BENCHMARK
./db_bench --use_existing_db -benchmarks=readtocache,readrandom[-X10] --num=5000000 --key_size=32 --disable_auto_compactions --reads=1000000 --block_protection_bytes_per_key=[0|1] --cache_size=$CACHESIZE

The readrandom ops/sec looks like the following:
Block cache size:  2GB        1.2GB * 0.9    1.2GB * 0.8     1.2GB * 0.5   8MB
Main              240805     223604         198176           161653       139040
PR prot_bytes=0   238691     226693         200127           161082       141153
PR prot_bytes=1   214983     193199         178532           137013       108211
prot_bytes=1 vs    -10%        -15%          -10.8%          -15%        -23%
prot_bytes=0
```

The benchmark has a lot of variance, but there was a 5% to 25% regression in this benchmark with different cache hit rates.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11287

Reviewed By: ajkr

Differential Revision: D43970708

Pulled By: cbi42

fbshipit-source-id: ef98d898b71779846fa74212b9ec9e08b7183940
2023-04-25 12:08:23 -07:00
Hui Xiao 151242ce46 Group rocksdb.sst.read.micros stat by IOActivity flush and compaction (#11288)
Summary:
**Context:**
The existing stat rocksdb.sst.read.micros does not reflect each of compaction and flush cases but aggregate them, which is not so helpful for us to understand IO read behavior of each of them.

**Summary**
- Update `StopWatch` and `RandomAccessFileReader` to record `rocksdb.sst.read.micros` and `rocksdb.file.{flush/compaction}.read.micros`
   - Fixed the default histogram in `RandomAccessFileReader`
- New field `ReadOptions/IOOptions::io_activity`; Pass `ReadOptions` through paths under db open, flush and compaction to where we can prepare `IOOptions` and pass it to `RandomAccessFileReader`
- Use `thread_status_util` for assertion in `DbStressFSWrapper` for continuous testing on we are passing correct `io_activity` under db open, flush and compaction

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11288

Test Plan:
- **Stress test**
- **Db bench 1: rocksdb.sst.read.micros COUNT ≈ sum of rocksdb.file.read.flush.micros's and rocksdb.file.read.compaction.micros's.**  (without blob)
     - May not be exactly the same due to `HistogramStat::Add` only guarantees atomic not accuracy across threads.
```
./db_bench -db=/dev/shm/testdb/ -statistics=true -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -target_file_size_base=655 -disable_auto_compactions=false -compression_type=none -bloom_bits=3 (-use_plain_table=1 -prefix_size=10)
```
```
// BlockBasedTable
rocksdb.sst.read.micros P50 : 2.009374 P95 : 4.968548 P99 : 8.110362 P100 : 43.000000 COUNT : 40456 SUM : 114805
rocksdb.file.read.flush.micros P50 : 1.871841 P95 : 3.872407 P99 : 5.540541 P100 : 43.000000 COUNT : 2250 SUM : 6116
rocksdb.file.read.compaction.micros P50 : 2.023109 P95 : 5.029149 P99 : 8.196910 P100 : 26.000000 COUNT : 38206 SUM : 108689

// PlainTable
Does not apply
```
- **Db bench 2: performance**

**Read**

SETUP: db with 900 files
```
./db_bench -db=/dev/shm/testdb/ -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655  -disable_auto_compactions=true -target_file_size_base=655 -compression_type=none
```run till convergence
```
./db_bench -seed=1678564177044286 -use_existing_db=true -db=/dev/shm/testdb -benchmarks=readrandom[-X60] -statistics=true -num=1000000 -disable_auto_compactions=true -compression_type=none -bloom_bits=3
```
Pre-change
`readrandom [AVG 60 runs] : 21568 (± 248) ops/sec`
Post-change (no regression, -0.3%)
`readrandom [AVG 60 runs] : 21486 (± 236) ops/sec`

**Compaction/Flush**run till convergence
```
./db_bench -db=/dev/shm/testdb2/ -seed=1678564177044286 -benchmarks="fillseq[-X60]" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655  -disable_auto_compactions=false -target_file_size_base=655 -compression_type=none

rocksdb.sst.read.micros  COUNT : 33820
rocksdb.sst.read.flush.micros COUNT : 1800
rocksdb.sst.read.compaction.micros COUNT : 32020
```
Pre-change
`fillseq [AVG 46 runs] : 1391 (± 214) ops/sec;    0.7 (± 0.1) MB/sec`

Post-change (no regression, ~-0.4%)
`fillseq [AVG 46 runs] : 1385 (± 216) ops/sec;    0.7 (± 0.1) MB/sec`

Reviewed By: ajkr

Differential Revision: D44007011

Pulled By: hx235

fbshipit-source-id: a54c89e4846dfc9a135389edf3f3eedfea257132
2023-04-21 09:07:18 -07:00
Hui Xiao cb58477185 New stat rocksdb.{cf|db}-write-stall-stats exposed in a structural way (#11300)
Summary:
**Context/Summary:**
Users are interested in figuring out what has caused write stall.
- Refactor write stall related stats from property `kCFStats` into its own db property `rocksdb.cf-write-stall-stats` as a map or string. For now, this only contains count of different combination of (CF-scope `WriteStallCause`) + (`WriteStallCondition`)
- Add new `WriteStallCause::kWriteBufferManagerLimit` to reflect write stall caused by write buffer manager
- Add new `rocksdb.db-write-stall-stats`. For now, this only contains `WriteStallCause::kWriteBufferManagerLimit` + `WriteStallCondition::kStopped`

- Expose functions in new class `WriteStallStatsMapKeys` for examining the above two properties returned as map
- Misc: rename/comment some write stall InternalStats for clarity

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11300

Test Plan:
- New UT
- Stress test
`python3 tools/db_crashtest.py blackbox --simple --get_property_one_in=1`
- Perf test: Both converge very slowly at similar rates but post-change has higher average ops/sec than pre-change even though they are run at the same time.
```
./db_bench -seed=1679014417652004 -db=/dev/shm/testdb/ -statistics=false -benchmarks="fillseq[-X60]" -key_size=32 -value_size=512 -num=100000 -db_write_buffer_size=655 -target_file_size_base=655 -disable_auto_compactions=false -compression_type=none -bloom_bits=3
```
pre-change:
```
fillseq [AVG 15 runs] : 1176 (± 732) ops/sec;    0.6 (± 0.4) MB/sec
fillseq      :    1052.671 micros/op 949 ops/sec 105.267 seconds 100000 operations;    0.5 MB/s
fillseq [AVG 16 runs] : 1162 (± 685) ops/sec;    0.6 (± 0.4) MB/sec
fillseq      :    1387.330 micros/op 720 ops/sec 138.733 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 17 runs] : 1136 (± 646) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1232.011 micros/op 811 ops/sec 123.201 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 18 runs] : 1118 (± 610) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1282.567 micros/op 779 ops/sec 128.257 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 19 runs] : 1100 (± 578) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1914.336 micros/op 522 ops/sec 191.434 seconds 100000 operations;    0.3 MB/s
fillseq [AVG 20 runs] : 1071 (± 551) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1227.510 micros/op 814 ops/sec 122.751 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 21 runs] : 1059 (± 525) ops/sec;    0.5 (± 0.3) MB/sec
```
post-change:
```
fillseq [AVG 15 runs] : 1226 (± 732) ops/sec;    0.6 (± 0.4) MB/sec
fillseq      :    1323.825 micros/op 755 ops/sec 132.383 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 16 runs] : 1196 (± 687) ops/sec;    0.6 (± 0.4) MB/sec
fillseq      :    1223.905 micros/op 817 ops/sec 122.391 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 17 runs] : 1174 (± 647) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1168.996 micros/op 855 ops/sec 116.900 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 18 runs] : 1156 (± 611) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1348.729 micros/op 741 ops/sec 134.873 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 19 runs] : 1134 (± 579) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1196.887 micros/op 835 ops/sec 119.689 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 20 runs] : 1119 (± 550) ops/sec;    0.6 (± 0.3) MB/sec
fillseq      :    1193.697 micros/op 837 ops/sec 119.370 seconds 100000 operations;    0.4 MB/s
fillseq [AVG 21 runs] : 1106 (± 524) ops/sec;    0.6 (± 0.3) MB/sec
```

Reviewed By: ajkr

Differential Revision: D44159541

Pulled By: hx235

fbshipit-source-id: 8d29efb70001fdc52d34535eeb3364fc3e71e40b
2023-03-18 09:51:58 -07:00
sdong 4720ba4391 Remove RocksDB LITE (#11147)
Summary:
We haven't been actively mantaining RocksDB LITE recently and the size must have been gone up significantly. We are removing the support.

Most of changes were done through following comments:

unifdef -m -UROCKSDB_LITE `git grep -l ROCKSDB_LITE | egrep '[.](cc|h)'`

by Peter Dillinger. Others changes were manually applied to build scripts, CircleCI manifests, ROCKSDB_LITE is used in an expression and file db_stress_test_base.cc.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11147

Test Plan: See CI

Reviewed By: pdillinger

Differential Revision: D42796341

fbshipit-source-id: 4920e15fc2060c2cd2221330a6d0e5e65d4b7fe2
2023-01-27 13:14:19 -08:00
Hui Xiao 86fa2592be Fix data race on ColumnFamilyData::flush_reason by letting FlushRequest/Job owns flush_reason instead of CFD (#11111)
Summary:
**Context:**
Concurrent flushes on the same CF can set on `ColumnFamilyData::flush_reason` before each other flush finishes. An symptom is one CF has different flush_reason with others though all of them are in an atomic flush  `db_stress: db/db_impl/db_impl_compaction_flush.cc:423: rocksdb::Status rocksdb::DBImpl::AtomicFlushMemTablesToOutputFiles(const rocksdb::autovector<rocksdb::DBImpl::BGFlushArg>&, bool*, rocksdb::JobContext*, rocksdb::LogBuffer*, rocksdb::Env::Priority): Assertion cfd->GetFlushReason() == cfds[0]->GetFlushReason() failed. `

**Summary:**
Suggested by ltamasi, we now refactor and let FlushRequest/Job to own flush_reason as there is no good way to define `ColumnFamilyData::flush_reason` in face of concurrent flushes on the same CF (which wasn't the case a long time ago when `ColumnFamilyData::flush_reason ` first introduced`)

**Tets:**
- new unit test
- make check
- aggressive crash test rehearsal

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11111

Reviewed By: ajkr

Differential Revision: D42644600

Pulled By: hx235

fbshipit-source-id: 8589c8184869d3415e5b780c887f877818a5ebaf
2023-01-24 09:54:04 -08:00
Hui Xiao 9502856edd Add missing range conflict check between file ingestion and RefitLevel() (#10988)
Summary:
**Context:**
File ingestion never checks whether the key range it acts on overlaps with an ongoing RefitLevel() (used in `CompactRange()` with `change_level=true`). That's because RefitLevel() doesn't register and make its key range known to file ingestion. Though it checks overlapping with other compactions by https://github.com/facebook/rocksdb/blob/7.8.fb/db/external_sst_file_ingestion_job.cc#L998.

RefitLevel() (used in `CompactRange()` with `change_level=true`) doesn't check whether the key range it acts on overlaps with an ongoing file ingestion. That's because file ingestion does not register and make its key range known to other compactions.
- Note that non-refitlevel-compaction (e.g, manual compaction w/o RefitLevel() or general compaction) also does not check key range overlap with ongoing file ingestion for the same reason.
- But it's fine. Credited to cbi42's discovery, `WaitForIngestFile` was called by background and foreground compactions. They were introduced in 0f88160f67, 5c64fb67d2 and 87dfc1d23e.
- Regardless, this PR registers file ingestion like a compaction is a general approach that will also add range conflict check between file ingestion and non-refitlevel-compaction, though it has not been the issue motivated this PR.

Above are bugs resulting in two bad consequences:
- If file ingestion and RefitLevel() creates files in the same level, then range-overlapped files will be created at that level and caught as corruption by `force_consistency_checks=true`
- If file ingestion and RefitLevel() creates file in different levels, then with one further compaction on the ingested file, it can result in two same keys both with seqno 0 in two different levels. Then with iterator's [optimization](c62f322169/db/db_iter.cc (L342-L343)) that assumes no two same keys both with seqno 0, it will either break this assertion in debug build or, even worst, return value of this same key for the key after it, which is the wrong value to return, in release build.

Therefore we decide to introduce range conflict check for file ingestion and RefitLevel() inspired from the existing range conflict check among compactions.

**Summary:**
- Treat file ingestion job and RefitLevel() as `Compaction` of new compaction reasons: `CompactionReason::kExternalSstIngestion` and `CompactionReason::kRefitLevel` and register/unregister them.  File ingestion is treated as compaction from L0 to different levels and RefitLevel() as compaction from source level to target level.
- Check for `RangeOverlapWithCompaction` with other ongoing compactions, `RegisterCompaction()` on this "compaction" before changing the LSM state in `VersionStorageInfo`, and `UnregisterCompaction()` after changing.
- Replace scattered fixes (0f88160f67, 5c64fb67d2 and 87dfc1d23e.) that prevents overlapping between file ingestion and non-refit-level compaction with this fix cuz those practices are easy to overlook.
- Misc: logic cleanup, see PR comments

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10988

Test Plan:
- New unit test `DBCompactionTestWithOngoingFileIngestionParam*` that failed pre-fix and passed afterwards.
- Made compatible with existing tests, see PR comments
- make check
- [Ongoing] Stress test rehearsal with normal value and aggressive CI value https://github.com/facebook/rocksdb/pull/10761

Reviewed By: cbi42

Differential Revision: D41535685

Pulled By: hx235

fbshipit-source-id: 549833a577ba1496d20a870583d4caa737da1258
2022-12-29 15:05:36 -08:00
Hui Xiao 98d5db5c2e Sort L0 files by newly introduced epoch_num (#10922)
Summary:
**Context:**
Sorting L0 files by `largest_seqno` has at least two inconvenience:
-  File ingestion and compaction involving ingested files can create files of overlapping seqno range with the existing files. `force_consistency_check=true` will catch such overlap seqno range even those harmless overlap.
    - For example, consider the following sequence of events ("key@n" indicates key at seqno "n")
       - insert k1@1 to memtable m1
       - ingest file s1 with k2@2, ingest file s2 with k3@3
        - insert k4@4 to m1
       - compact files s1, s2 and  result in new file s3 of seqno range [2, 3]
       - flush m1 and result in new file s4 of seqno range [1, 4]. And `force_consistency_check=true` will think s4 and s3 has file reordering corruption that might cause retuning an old value of k1
    - However such caught corruption is a false positive since s1, s2 will not have overlapped keys with k1 or whatever inserted into m1 before ingest file s1 by the requirement of file ingestion (otherwise the m1 will be flushed first before any of the file ingestion completes). Therefore there in fact isn't any file reordering corruption.
- Single delete can decrease a file's largest seqno and ordering by `largest_seqno` can introduce a wrong ordering hence file reordering corruption
    - For example, consider the following sequence of events ("key@n" indicates key at seqno "n", Credit to ajkr  for this example)
        - an existing SST s1 contains only k1@1
        - insert k1@2 to memtable m1
        - ingest file s2 with k3@3, ingest file s3 with k4@4
        - insert single delete k5@5 in m1
        - flush m1 and result in new file s4 of seqno range [2, 5]
        - compact s1, s2, s3 and result in new file s5 of seqno range [1, 4]
        - compact s4 and result in new file s6 of seqno range [2] due to single delete
    - By the last step, we have file ordering by largest seqno (">" means "newer") : s5 > s6 while s6 contains a newer version of the k1's value (i.e, k1@2) than s5, which is a real reordering corruption. While this can be caught by `force_consistency_check=true`, there isn't a good way to prevent this from happening if ordering by `largest_seqno`

Therefore, we are redesigning the sorting criteria of L0 files and avoid above inconvenience. Credit to ajkr , we now introduce `epoch_num` which describes the order of a file being flushed or ingested/imported (compaction output file will has the minimum `epoch_num` among input files'). This will avoid the above inconvenience in the following ways:
- In the first case above, there will no longer be overlap seqno range check in `force_consistency_check=true` but `epoch_number`  ordering check. This will result in file ordering s1 <  s2 <  s4 (pre-compaction) and s3 < s4 (post-compaction) which won't trigger false positive corruption. See test class `DBCompactionTestL0FilesMisorderCorruption*` for more.
- In the second case above, this will result in file ordering s1 < s2 < s3 < s4 (pre-compacting s1, s2, s3), s5 < s4 (post-compacting s1, s2, s3), s5 < s6 (post-compacting s4), which are correct file ordering without causing any corruption.

**Summary:**
- Introduce `epoch_number` stored per `ColumnFamilyData` and sort CF's L0 files by their assigned `epoch_number` instead of `largest_seqno`.
  - `epoch_number` is increased and assigned upon `VersionEdit::AddFile()` for flush (or similarly for WriteLevel0TableForRecovery) and file ingestion (except for allow_behind_true, which will always get assigned as the `kReservedEpochNumberForFileIngestedBehind`)
  - Compaction output file  is assigned with the minimum `epoch_number` among input files'
      - Refit level: reuse refitted file's epoch_number
  -  Other paths needing `epoch_number` treatment:
     - Import column families: reuse file's epoch_number if exists. If not, assign one based on `NewestFirstBySeqNo`
     - Repair: reuse file's epoch_number if exists. If not, assign one based on `NewestFirstBySeqNo`.
  -  Assigning new epoch_number to a file and adding this file to LSM tree should be atomic. This is guaranteed by us assigning epoch_number right upon `VersionEdit::AddFile()` where this version edit will be apply to LSM tree shape right after by holding the db mutex (e.g, flush, file ingestion, import column family) or  by there is only 1 ongoing edit per CF (e.g, WriteLevel0TableForRecovery, Repair).
  - Assigning the minimum input epoch number to compaction output file won't misorder L0 files (even through later `Refit(target_level=0)`). It's due to for every key "k" in the input range, a legit compaction will cover a continuous epoch number range of that key. As long as we assign the key "k" the minimum input epoch number, it won't become newer or older than the versions of this key that aren't included in this compaction hence no misorder.
- Persist `epoch_number` of each file in manifest and recover `epoch_number` on db recovery
   - Backward compatibility with old db without `epoch_number` support is guaranteed by assigning `epoch_number` to recovered files by `NewestFirstBySeqno` order. See `VersionStorageInfo::RecoverEpochNumbers()` for more
   - Forward compatibility with manifest is guaranteed by flexibility of `NewFileCustomTag`
- Replace `force_consistent_check` on L0 with `epoch_number` and remove false positive check like case 1 with `largest_seqno` above
   - Due to backward compatibility issue, we might encounter files with missing epoch number at the beginning of db recovery. We will still use old L0 sorting mechanism (`NewestFirstBySeqno`) to check/sort them till we infer their epoch number. See usages of `EpochNumberRequirement`.
- Remove fix https://github.com/facebook/rocksdb/pull/5958#issue-511150930 and their outdated tests to file reordering corruption because such fix can be replaced by this PR.
- Misc:
   - update existing tests with `epoch_number` so make check will pass
   - update https://github.com/facebook/rocksdb/pull/5958#issue-511150930 tests to verify corruption is fixed using `epoch_number` and cover universal/fifo compaction/CompactRange/CompactFile cases
   - assert db_mutex is held for a few places before calling ColumnFamilyData::NewEpochNumber()

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10922

Test Plan:
- `make check`
- New unit tests under `db/db_compaction_test.cc`, `db/db_test2.cc`, `db/version_builder_test.cc`, `db/repair_test.cc`
- Updated tests (i.e, `DBCompactionTestL0FilesMisorderCorruption*`) under https://github.com/facebook/rocksdb/pull/5958#issue-511150930
- [Ongoing] Compatibility test: manually run 36a5686ec0 (with file ingestion off for running the `.orig` binary to prevent this bug affecting upgrade/downgrade formality checking) for 1 hour on `simple black/white box`, `cf_consistency/txn/enable_ts with whitebox + test_best_efforts_recovery with blackbox`
- [Ongoing] normal db stress test
- [Ongoing] db stress test with aggressive value https://github.com/facebook/rocksdb/pull/10761

Reviewed By: ajkr

Differential Revision: D41063187

Pulled By: hx235

fbshipit-source-id: 826cb23455de7beaabe2d16c57682a82733a32a9
2022-12-13 13:29:37 -08:00
Hui Xiao f1574a20ff Revert PR 10777 "Fix FIFO causing overlapping seqnos in L0 files due to overla…" (#10999)
Summary:
**Context/Summary:**

This reverts commit fc74abb436 and related HISTORY record.

The issue with PR 10777 or general approach using earliest_mem_seqno like https://github.com/facebook/rocksdb/pull/5958#issue-511150930 is that the earliest seqno of memtable of each CFs does not get persisted and will always start with 0 upon Recover(). Later when creating a new memtable in certain CF, we use the last seqno of the whole DB (but not of that CF from previous DB session) for this CF.  This will lead to false positive overlapping seqno and PR 10777 will throw something like https://github.com/facebook/rocksdb/blob/main/db/compaction/compaction_picker.cc#L1002-L1004

Luckily a more elegant and complete solution to the overlapping seqno problem these PR aim to solve does not have above problem, see https://github.com/facebook/rocksdb/pull/10922. It is already being pursued and in the process of review. So we can just revert this PR and focus on getting PR10922 to land.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10999

Test Plan: make check

Reviewed By: anand1976

Differential Revision: D41572604

Pulled By: hx235

fbshipit-source-id: 9d9bdf594abd235e2137045cef513ca0b14e0a3a
2022-11-29 10:56:42 -08:00
Andrew Kryczka 5cf6ab6f31 Ran clang-format on db/ directory (#10910)
Summary:
Ran `find ./db/ -type f | xargs clang-format -i`. Excluded minor changes it tried to make on db/db_impl/. Everything else it changed was directly under db/ directory. Included minor manual touchups mentioned in PR commit history.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10910

Reviewed By: riversand963

Differential Revision: D40880683

Pulled By: ajkr

fbshipit-source-id: cfe26cda05b3fb9a72e3cb82c286e21d8c5c4174
2022-11-02 14:34:24 -07:00
Hui Xiao fc74abb436 Fix FIFO causing overlapping seqnos in L0 files due to overlapped seqnos between ingested files and memtable's (#10777)
Summary:
**Context:**
Same as https://github.com/facebook/rocksdb/pull/5958#issue-511150930 but apply the fix to FIFO Compaction case
Repro:
```
COERCE_CONTEXT_SWICH=1 make -j56 db_stress

./db_stress --acquire_snapshot_one_in=0 --adaptive_readahead=0 --allow_data_in_errors=True --async_io=1 --avoid_flush_during_recovery=0 --avoid_unnecessary_blocking_io=0 --backup_max_size=104857600 --backup_one_in=0 --batch_protection_bytes_per_key=0 --block_size=16384 --bloom_bits=18 --bottommost_compression_type=disable --bytes_per_sync=262144 --cache_index_and_filter_blocks=0 --cache_size=8388608 --cache_type=lru_cache --charge_compression_dictionary_building_buffer=0 --charge_file_metadata=1 --charge_filter_construction=1 --charge_table_reader=1 --checkpoint_one_in=0 --checksum_type=kCRC32c --clear_column_family_one_in=0 --column_families=1 --compact_files_one_in=0 --compact_range_one_in=1000 --compaction_pri=3 --open_files=-1 --compaction_style=2 --fifo_allow_compaction=1 --compaction_ttl=0 --compression_max_dict_buffer_bytes=8388607 --compression_max_dict_bytes=16384 --compression_parallel_threads=1 --compression_type=zlib --compression_use_zstd_dict_trainer=1 --compression_zstd_max_train_bytes=0 --continuous_verification_interval=0 --data_block_index_type=0 --db=/dev/shm/rocksdb_test0/rocksdb_crashtest_whitebox --db_write_buffer_size=8388608 --delpercent=4 --delrangepercent=1 --destroy_db_initially=1 --detect_filter_construct_corruption=0 --disable_wal=0 --enable_compaction_filter=0 --enable_pipelined_write=1 --fail_if_options_file_error=1 --file_checksum_impl=none --flush_one_in=1000 --format_version=5 --get_current_wal_file_one_in=0 --get_live_files_one_in=0 --get_property_one_in=0 --get_sorted_wal_files_one_in=0 --index_block_restart_interval=15 --index_type=3 --ingest_external_file_one_in=100 --initial_auto_readahead_size=0 --iterpercent=10 --key_len_percent_dist=1,30,69 --level_compaction_dynamic_level_bytes=True --log2_keys_per_lock=10 --long_running_snapshots=0 --mark_for_compaction_one_file_in=10 --max_auto_readahead_size=16384 --max_background_compactions=20 --max_bytes_for_level_base=10485760 --max_key=100000 --max_key_len=3 --max_manifest_file_size=1073741824 --max_write_batch_group_size_bytes=1048576 --max_write_buffer_number=3 --max_write_buffer_size_to_maintain=4194304 --memtable_prefix_bloom_size_ratio=0.5 --memtable_protection_bytes_per_key=1 --memtable_whole_key_filtering=1 --memtablerep=skip_list --mmap_read=1 --mock_direct_io=False --nooverwritepercent=1 --num_file_reads_for_auto_readahead=0 --num_levels=1 --open_metadata_write_fault_one_in=0 --open_read_fault_one_in=32 --open_write_fault_one_in=0 --ops_per_thread=200000 --optimize_filters_for_memory=0 --paranoid_file_checks=1 --partition_filters=0 --partition_pinning=1 --pause_background_one_in=0 --periodic_compaction_seconds=0 --prefix_size=8 --prefixpercent=5 --prepopulate_block_cache=0 --progress_reports=0 --read_fault_one_in=0 --readahead_size=16384 --readpercent=45 --recycle_log_file_num=1 --reopen=20 --ribbon_starting_level=999 --snapshot_hold_ops=1000 --sst_file_manager_bytes_per_sec=0 --sst_file_manager_bytes_per_truncate=0 --subcompactions=2 --sync=0 --sync_fault_injection=0 --target_file_size_base=524288 --target_file_size_multiplier=2 --test_batches_snapshots=0 --top_level_index_pinning=3 --unpartitioned_pinning=0 --use_direct_io_for_flush_and_compaction=0 --use_direct_reads=0 --use_full_merge_v1=1 --use_merge=0 --use_multiget=1 --user_timestamp_size=0 --value_size_mult=32 --verify_checksum=1 --verify_checksum_one_in=0 --verify_db_one_in=1000 --verify_sst_unique_id_in_manifest=1 --wal_bytes_per_sync=0 --wal_compression=zstd --write_buffer_size=524288 --write_dbid_to_manifest=0 --writepercent=35

put or merge error: Corruption: force_consistency_checks(DEBUG): VersionBuilder: L0 file https://github.com/facebook/rocksdb/issues/479 with seqno 23711 29070 vs. file https://github.com/facebook/rocksdb/issues/482 with seqno 27138 29049
```

**Summary:**
FIFO only does intra-L0 compaction in the following four cases. For other cases, FIFO drops data instead of compacting on data, which is irrelevant to the overlapping seqno issue we are solving.
-  [FIFOCompactionPicker::PickSizeCompaction](https://github.com/facebook/rocksdb/blob/7.6.fb/db/compaction/compaction_picker_fifo.cc#L155) when `total size < compaction_options_fifo.max_table_files_size` and `compaction_options_fifo.allow_compaction == true`
   - For this path, we simply reuse the fix in `FindIntraL0Compaction` https://github.com/facebook/rocksdb/pull/5958/files#diff-c261f77d6dd2134333c4a955c311cf4a196a08d3c2bb6ce24fd6801407877c89R56
   - This path was not stress-tested at all. Therefore we covered `fifo.allow_compaction` in stress test to surface the overlapping seqno issue we are fixing here.
- [FIFOCompactionPicker::PickCompactionToWarm](https://github.com/facebook/rocksdb/blob/7.6.fb/db/compaction/compaction_picker_fifo.cc#L313) when `compaction_options_fifo.age_for_warm > 0`
  - For this path, we simply replicate the idea in https://github.com/facebook/rocksdb/pull/5958#issue-511150930 and skip files of largest seqno greater than `earliest_mem_seqno`
  - This path was not stress-tested at all. However covering `age_for_warm` option worths a separate PR to deal with db stress compatibility. Therefore we manually tested this path for this PR
- [FIFOCompactionPicker::CompactRange](https://github.com/facebook/rocksdb/blob/7.6.fb/db/compaction/compaction_picker_fifo.cc#L365) that ends up picking one of the above two compactions
- [CompactionPicker::CompactFiles](https://github.com/facebook/rocksdb/blob/7.6.fb/db/compaction/compaction_picker.cc#L378)
    - Since `SanitizeCompactionInputFiles()` will be called [before](https://github.com/facebook/rocksdb/blob/7.6.fb/db/compaction/compaction_picker.h#L111-L113) `CompactionPicker::CompactFiles` , we simply replicate the idea in https://github.com/facebook/rocksdb/pull/5958#issue-511150930  in `SanitizeCompactionInputFiles()`. To simplify implementation, we return `Stats::Abort()` on encountering seqno-overlapped file when doing compaction to L0 instead of skipping the file and proceed with the compaction.

Some additional clean-up included in this PR:
- Renamed `earliest_memtable_seqno` to `earliest_mem_seqno` for consistent naming
- Added comment about `earliest_memtable_seqno` in related APIs
- Made parameter `earliest_memtable_seqno` constant and required

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10777

Test Plan:
- make check
- New unit test `TEST_P(DBCompactionTestFIFOCheckConsistencyWithParam, FlushAfterIntraL0CompactionWithIngestedFile)`corresponding to the above 4 cases, which will fail accordingly without the fix
- Regular CI stress run on this PR + stress test with aggressive value https://github.com/facebook/rocksdb/pull/10761  and on FIFO compaction only

Reviewed By: ajkr

Differential Revision: D40090485

Pulled By: hx235

fbshipit-source-id: 52624186952ee7109117788741aeeac86b624a4f
2022-10-25 10:39:58 -07:00
Yueh-Hsuan Chiang e267909ecf Enable a multi-level db to smoothly migrate to FIFO via DB::Open (#10348)
Summary:
FIFO compaction can theoretically open a DB with any compaction style.
However, the current code only allows FIFO compaction to open a DB with
a single level.

This PR relaxes the limitation of FIFO compaction and allows it to open a
DB with multiple levels.  Below is the read / write / compaction behavior:

* The read behavior is untouched, and it works like a regular rocksdb instance.
* The write behavior is untouched as well.  When a FIFO compacted DB
is opened with multiple levels, all new files will still be in level 0, and no files
will be moved to a different level.
* Compaction logic is extended.  It will first identify the bottom-most non-empty level.
Then, it will delete the oldest file in that level.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10348

Test Plan:
Added a new test to verify the migration from level to FIFO where the db has multiple levels.
Extended existing test cases in db_test and db_basic_test to also verify
all entries of a key after reopening the DB with FIFO compaction.

Reviewed By: jay-zhuang

Differential Revision: D40233744

fbshipit-source-id: 6cc011d6c3467e6bfb9b6a4054b87619e69815e1
2022-10-18 14:38:13 -07:00
Yanqin Jin 4d82b94896 Sanitize min_write_buffer_number_to_merge to 1 with atomic_flush (#10773)
Summary:
With current implementation, within the same RocksDB instance, all column families with non-empty memtables will be scheduled for flush if RocksDB determines that any column family needs to be flushed, e.g. memtable full, write buffer manager, etc., if atomic flush is enabled. Not doing so can lead to data loss and inconsistency when WAL is disabled, which is a common setting when atomic flush is enabled. Therefore, setting a per-column-family knob, min_write_buffer_number_to_merge to a value greater than 1 is not compatible with atomic flush, and should be sanitized during column family creation and db open.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10773

Test Plan:
Reproduce: D39993203 has detailed steps.
Run the test with and without the fix.

Reviewed By: cbi42

Differential Revision: D40077955

Pulled By: cbi42

fbshipit-source-id: 451a9179eb531ac42eaccf40b451b9dec4085240
2022-10-05 12:24:39 -07:00
Changyu Bi 749b849a34 Fix memtable-only iterator regression (#10705)
Summary:
when there is a single memtable without range tombstones and no SST files in the database, DBIter should wrap memtable iterator directly. Currently we create a merging iterator on top of the memtable iterator, and have DBIter wrap around it. This causes iterator regression and this PR fixes this issue.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10705

Test Plan:
- `make check`
- Performance:
  - Set up: `./db_bench -benchmarks=filluniquerandom -write_buffer_size=$((1 << 30)) -num=10000`
  - Benchmark: `./db_bench -benchmarks=seekrandom -use_existing_db=true -avoid_flush_during_recovery=true -write_buffer_size=$((1 << 30)) -num=10000 -threads=16 -duration=60 -seek_nexts=$seek_nexts`
```
seek_nexts    main op/sec    https://github.com/facebook/rocksdb/issues/10705      RocksDB v7.6
0             5746568        5749033     5786180
30            2411690        3006466     2837699
1000          102556         128902      124667
```

Reviewed By: ajkr

Differential Revision: D39644221

Pulled By: cbi42

fbshipit-source-id: 8063ff611ba31b0e5670041da3927c8c54b2097d
2022-09-21 09:49:31 -07:00
Changyu Bi 3a75219e5d Validate option memtable_protection_bytes_per_key (#10621)
Summary:
sanity check value for option `memtable_protection_bytes_per_key` in `ColumnFamilyData::ValidateOptions()`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10621

Test Plan: `make check`, added unit test in ColumnFamilyTest.

Reviewed By: ajkr

Differential Revision: D39180133

Pulled By: cbi42

fbshipit-source-id: 009e0da3ccb332d1c9e14d20193304610bd4eb8a
2022-08-31 17:47:07 -07:00
Changyu Bi 9d77bf8f7b Fragment memtable range tombstone in the write path (#10380)
Summary:
- Right now each read fragments the memtable range tombstones https://github.com/facebook/rocksdb/issues/4808. This PR explores the idea of fragmenting memtable range tombstones in the write path and reads can just read this cached fragmented tombstone without any fragmenting cost. This PR only does the caching for immutable memtable, and does so right before a memtable is added to an immutable memtable list. The fragmentation is done without holding mutex to minimize its performance impact.
- db_bench is updated to print out the number of range deletions executed if there is any.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10380

Test Plan:
- CI, added asserts in various places to check whether a fragmented range tombstone list should have been constructed.
- Benchmark: as this PR only optimizes immutable memtable path, the number of writes in the benchmark is chosen such  an immutable memtable is created and range tombstones are in that memtable.

```
single thread:
./db_bench --benchmarks=fillrandom,readrandom --writes_per_range_tombstone=1 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=500000 --reads=100000 --max_num_range_tombstones=100

multi_thread
./db_bench --benchmarks=fillrandom,readrandom --writes_per_range_tombstone=1 --max_write_buffer_number=100 --min_write_buffer_number_to_merge=100 --writes=15000 --reads=20000 --threads=32 --max_num_range_tombstones=100
```
Commit 99cdf16464 is included in benchmark result. It was an earlier attempt where tombstones are fragmented for each write operation. Reader threads share it using a shared_ptr which would slow down multi-thread read performance as seen in benchmark results.
Results are averaged over 5 runs.

Single thread result:
| Max # tombstones  | main fillrandom micros/op | 99cdf16464 | Post PR | main readrandom micros/op |  99cdf16464 | Post PR |
| ------------- | ------------- |------------- |------------- |------------- |------------- |------------- |
| 0    |6.68     |6.57     |6.72     |4.72     |4.79     |4.54     |
| 1    |6.67     |6.58     |6.62     |5.41     |4.74     |4.72     |
| 10   |6.59     |6.5      |6.56     |7.83     |4.69     |4.59     |
| 100  |6.62     |6.75     |6.58     |29.57    |5.04     |5.09     |
| 1000 |6.54     |6.82     |6.61     |320.33   |5.22     |5.21     |

32-thread result: note that "Max # tombstones" is per thread.
| Max # tombstones  | main fillrandom micros/op | 99cdf16464 | Post PR | main readrandom micros/op |  99cdf16464 | Post PR |
| ------------- | ------------- |------------- |------------- |------------- |------------- |------------- |
| 0    |234.52   |260.25   |239.42   |5.06     |5.38     |5.09     |
| 1    |236.46   |262.0    |231.1    |19.57    |22.14    |5.45     |
| 10   |236.95   |263.84   |251.49   |151.73   |21.61    |5.73     |
| 100  |268.16   |296.8    |280.13   |2308.52  |22.27    |6.57     |

Reviewed By: ajkr

Differential Revision: D37916564

Pulled By: cbi42

fbshipit-source-id: 05d6d2e16df26c374c57ddcca13a5bfe9d5b731e
2022-08-05 12:02:33 -07:00
Peter Dillinger 27f3af5966 Fix serious FSDirectory use-after-Close bug (missing fsync) (#10460)
Summary:
TL;DR: due to a recent change, if you drop a column family,
often that DB will no longer fsync after writing new SST files
to remaining or new column families, which could lead to data
loss on power loss.

More bug detail:
The intent of https://github.com/facebook/rocksdb/issues/10049 was to Close FSDirectory objects at
DB::Close time rather than waiting for DB object destruction.
Unfortunately, it also closes shared FSDirectory objects on
DropColumnFamily (& destroy remaining handles), which can lead
to use-after-Close on FSDirectory shared with remaining column
families. Those "uses" are only Fsyncs (or redundant Closes). In
the default Posix filesystem, an Fsync on a closed FSDirectory is a
quiet no-op. Consequently (under most configurations), if you drop
a column family, that DB will no longer fsync after writing new SST
files to column families sharing the same directory (true under most
configurations).

More fix detail:
Basically, this removes unnecessary Close ops on destroying
ColumnFamilyData. We let `shared_ptr` take care of calling the
destructor at the right time. If the intent was to require Close be
called before destroying FSDirectory, that was not made clear by the
author of FileSystem and was not at all enforced by https://github.com/facebook/rocksdb/issues/10049, which
could have added `assert(fd_ == -1)` to `~PosixDirectory()` but did
not. To keep this fix simple, we relax the unit test for https://github.com/facebook/rocksdb/issues/10049 to allow
timely destruction of FSDirectory to suffice as Close (in
CountedFileSystem). Added a TODO to revisit that.

Also in this PR:
* Added a TODO to share FSDirectory instances between DB and its column
families. (Already shared among column families.)
* Made DB::Close attempt to close all its open FSDirectory objects even
if there is a failure in closing one. Also code clean-up around this
logic.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10460

Test Plan:
add an assert to check for use-after-Close. With that
existing tests can detect the misuse. With fix, tests pass (except noted
relaxing of unit test for https://github.com/facebook/rocksdb/issues/10049)

Reviewed By: ajkr

Differential Revision: D38357922

Pulled By: pdillinger

fbshipit-source-id: d42079cadbedf0a969f03389bf586b3b4e1f9137
2022-08-02 10:54:32 -07:00
Yu Zhao 00540916 bfc737da21 fix typos in some code and comment (#10139)
Summary:
Minor issue, I just found a few typos on db_test and column_family while reading the code. And I have this PR opened to contribute.  :)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10139

Reviewed By: ajkr

Differential Revision: D38007098

Pulled By: jay-zhuang

fbshipit-source-id: 511947b32424c34348184691216640f32c410fb1
2022-07-22 19:25:52 -07:00
sdong 6115254416 Fix A Bug Where Concurrent Compactions Cause Further Slowing Down (#10270)
Summary:
Currently, when installing a new super version, when stalling condition triggers, we compare estimated compaction bytes to previously, and if the new value is larger or equal to the previous one, we reduce the slowdown write rate. However, if concurrent compactions happen, the same value might be used. The result is that, although some compactions reduce estimated compaction bytes, we treat them as a signal for further slowing down. In some cases, it causes slowdown rate drops all the way to the minimum, far lower than needed.

Fix the bug by not triggering a re-calculation if a new super version doesn't have Version or a memtable change. With this fix, number of compaction finishes are still undercounted in this algorithm, but it is still better than the current bug where they are negatively counted.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10270

Test Plan: Run a benchmark where the slowdown rate is dropped to minimal unnessarily and see it is back to a normal value.

Reviewed By: ajkr

Differential Revision: D37497327

fbshipit-source-id: 9bca961cc38fed965c3af0fa6c9ca0efaa7637c4
2022-06-29 11:20:36 -07:00
Baptiste Lemaire 5879053fd0 Dynamically changeable MemPurge option (#10011)
Summary:
**Summary**
Make the mempurge option flag a Mutable Column Family option flag. Therefore, the mempurge feature can be dynamically toggled.

**Motivation**
RocksDB users prefer having the ability to switch features on and off without having to close and reopen the DB. This is particularly important if the feature causes issues and needs to be turned off. Dynamically changing a DB option flag does not seem currently possible.
Moreover, with this new change, the MemPurge feature can be toggled on or off independently between column families, which we see as a major improvement.

**Content of this PR**
This PR includes removal of the `experimental_mempurge_threshold` flag as a DB option flag, and its re-introduction as a `MutableCFOption` flag. I updated the code to handle dynamic changes of the flag (in particular inside the `FlushJob` file). Additionally, this PR includes a new test to demonstrate the capacity of the code to toggle the MemPurge feature on and off, as well as the addition in the `db_stress` module of 2 different mempurge threshold values (0.0 and 1.0) that can be randomly changed with the `set_option_one_in` flag. This is useful to stress test the dynamic changes.

**Benchmarking**
I will add numbers to prove that there is no performance impact within the next 12 hours.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10011

Reviewed By: pdillinger

Differential Revision: D36462357

Pulled By: bjlemaire

fbshipit-source-id: 5e3d63bdadf085c0572ecc2349e7dd9729ce1802
2022-06-23 09:42:18 -07:00
Gang Liao deff48bcef Add blob source to retrieve blobs in RocksDB (#10198)
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
In this task, we formally introduced the blob source to RocksDB.  BlobSource is a new abstraction layer that provides universal access to blobs, regardless of whether they are in the blob cache, secondary cache, or (remote) storage. Depending on user settings, it always fetch blobs from multi-tier cache and storage with minimal cost.

Note: The new `MultiGetBlob()` implementation is not included in the current PR. To go faster, we aim to create a separate PR for it in parallel!

This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10198

Reviewed By: ltamasi

Differential Revision: D37294735

Pulled By: gangliao

fbshipit-source-id: 9cb50422d9dd1bc03798501c2778b6c7520c7a1e
2022-06-20 20:58:11 -07:00