Commit graph

133 commits

Author SHA1 Message Date
Peter Dillinger 4e60663b31 Remove unnecessary, confusing 'extern' (#12300)
Summary:
In C++, `extern` is redundant in a number of cases:
* "Global" function declarations and definitions
* "Global" variable definitions when already declared `extern`

For consistency and simplicity, I've removed these in code that *we own*. In a couple of cases, I removed obsolete declarations, and for MagicNumber constants, I have consolidated the declarations into a header file (format.h)
as standard best practice would prescribe.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12300

Test Plan: no functional changes, CI

Reviewed By: ajkr

Differential Revision: D53148629

Pulled By: pdillinger

fbshipit-source-id: fb8d927959892e03af09b0c0d542b0a3b38fd886
2024-01-29 10:38:08 -08:00
Yu Zhang 509947ce2c Quarantine files in a limbo state after a manifest error (#12030)
Summary:
Part of the procedures to handle manifest IO error is to disable file deletion in case some files in limbo state get deleted prematurely. This is not ideal because: 1) not all the VersionEdits whose commit encounter such an error contain updates for files, disabling file deletion sometimes are not necessary. 2) `EnableFileDeletion` has a force mode that could make other threads accidentally disrupt this procedure in recovery.  3) Disabling file deletion as a whole is also not as efficient as more precisely tracking impacted files from being prematurely deleted.  This PR replaces this mechanism with tracking such files and quarantine them from being deleted in `ErrorHandler`.

These are the types of files being actively tracked in quarantine in this PR:
1) new table files and blob files from a background job
2) old manifest file whose immediately following new manifest file's CURRENT file creation gets into unclear state. Current handling is not sufficient to make sure the old manifest file is kept in case it's needed.

Note that WAL logs are not part of the quarantine because `min_log_number_to_keep` is a safe mechanism and it's only updated after successful manifest commits so it can prevent this premature deletion issue from happening.

We track these files' file numbers because they share the same file number space.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12030

Test Plan: Modified existing unit tests

Reviewed By: ajkr

Differential Revision: D51036774

Pulled By: jowlyzhang

fbshipit-source-id: 84ef26271fbbc888ef70da5c40fe843bd7038716
2023-11-11 08:11:11 -08:00
Yu Zhang 4b013dcbed Remove VersionEdit's friends pattern (#12024)
Summary:
Almost each of VersionEdit private member has its own getter and setter. Current code access them with a combination of directly accessing private members and via getter and setters. There is no obvious benefits to have this pattern except potential performance gains. I tried this simple benchmark for removing the friends pattern completely, and there is no obvious regression. So I think it would good to remove VersionEdit's friends completely.

```TEST_TMPDIR=/dev/shm/rocksdb1 ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num_column_families=10 -num=50000000```

With change:
fillseq      :       2.994 micros/op 333980 ops/sec 149.710 seconds 50000000 operations;   36.9 MB/s
fillseq      :       3.033 micros/op 329656 ops/sec 151.673 seconds 50000000 operations;   36.5 MB/s
fillseq      :       2.991 micros/op 334369 ops/sec 149.535 seconds 50000000 operations;   37.0 MB/s
Without change:
fillseq      :       3.015 micros/op 331715 ops/sec 150.732 seconds 50000000 operations;   36.7 MB/s
fillseq      :       3.044 micros/op 328553 ops/sec 152.182 seconds 50000000 operations;   36.3 MB/s
fillseq      :       3.091 micros/op 323520 ops/sec 154.550 seconds 50000000 operations;   35.8 MB/s

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12024

Reviewed By: pdillinger

Differential Revision: D50806066

Pulled By: jowlyzhang

fbshipit-source-id: 35d287ce638a38c30f243f85992e615b4c90eb27
2023-11-01 12:04:11 -07:00
Hui Xiao 8e949116f7 Fix comments about creation_time/oldest_ancester_time/oldest_key_time (#11921)
Summary:
Code reference for the comments change:

40b618f234/table/block_based/block_based_table_builder.cc?fbclid=IwAR0JlfnG8wysclFP5wv0fSngFbi_j32BUCKbFayeGdr10tzDhyyk5QqpclA#L2093

40b618f234/db/flush_job.cc?fbclid=IwAR1ri6eTX3wyD_2fAEBRzFSwZItcbmDS8LaB11k1letDMQmB2L8nF6TfXDs#L945-L949

40b618f234/db/compaction/compaction_job.cc (L1882-L1904)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11921

Reviewed By: cbi42

Differential Revision: D49921304

Pulled By: hx235

fbshipit-source-id: 2ae17e43c0fd52044404d7b63fea254d2d1f3595
2023-10-04 14:42:35 -07:00
Changyu Bi 6a0f637633 Compare the number of input keys and processed keys for compactions (#11571)
Summary:
... to improve data integrity validation during compaction.

A new option `compaction_verify_record_count` is introduced for this verification and is enabled by default. One exception when the verification is not done is when a compaction filter returns kRemoveAndSkipUntil which can cause CompactionIterator to seek until some key and hence not able to keep track of the number of keys processed.

For expected number of input keys, we sum over the number of total keys - number of range tombstones across compaction input files (`CompactionJob::UpdateCompactionStats()`). Table properties are consulted if `FileMetaData` is not initialized for some input file. Since table properties for all input files were also constructed during `DBImpl::NotifyOnCompactionBegin()`, `Compaction::GetTableProperties()` is introduced to reduce duplicated code.

For actual number of keys processed, each subcompaction will record its number of keys processed to `sub_compact->compaction_job_stats.num_input_records` and aggregated when all subcompactions finish (`CompactionJob::AggregateCompactionStats()`). In the case when some subcompaction encountered kRemoveAndSkipUntil from compaction filter and does not have accurate count, it propagates this information through `sub_compact->compaction_job_stats.has_num_input_records`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11571

Test Plan:
* Add a new unit test `DBCompactionTest.VerifyRecordCount` for the corruption case.
* All other unit tests for non-corrupted case.
* Ran crash test for a few hours: `python3 ./tools/db_crashtest.py whitebox --simple`

Reviewed By: ajkr

Differential Revision: D47131965

Pulled By: cbi42

fbshipit-source-id: cc8e94565dd526c4347e9d3843ecf32f6727af92
2023-07-28 09:47:31 -07:00
Yu Zhang c24ef26ca7 Support switching on / off UDT together with in-Memtable-only feature (#11623)
Summary:
Add support to allow enabling / disabling user-defined timestamps feature for an existing column family in combination with the in-Memtable only feature.

To do this, this PR includes:
1) Log the `persist_user_defined_timestamps` option per column family in Manifest to facilitate detecting an attempt to enable / disable UDT. This entry is enforced to be logged in the same VersionEdit as the user comparator name entry.

2) User-defined timestamps related options are validated when re-opening a column family, including user comparator name and the `persist_user_defined_timestamps` flag. These type of settings and settings change are considered valid:
     a) no user comparator change and no effective `persist_user_defined_timestamp` flag change.
     b) switch user comparator to enable UDT provided the immediately effective `persist_user_defined_timestamps` flag
         is false.
     c) switch user comparator to disable UDT provided that the before-change `persist_user_defined_timestamps` is
         already false.
3) when an attempt to enable UDT is detected, we mark all its existing SST files as "having no UDT" by marking its `FileMetaData.user_defined_timestamps_persisted` flag to false and handle their file boundaries `FileMetaData.smallest`, `FileMetaData.largest` by padding a min timestamp.

4) while enabling / disabling UDT feature, timestamp size inconsistency in existing WAL logs are handled to make it compatible with the running user comparator.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11623

Test Plan:
```
make all check
./db_with_timestamp_basic_test --gtest-filter="*EnableDisableUDT*"
./db_wal_test --gtest_filter="*EnableDisableUDT*"
```

Reviewed By: ltamasi

Differential Revision: D47636862

Pulled By: jowlyzhang

fbshipit-source-id: dcd19f67292da3c3cc9584c09ad00331c9ab9322
2023-07-26 20:16:32 -07:00
Yu Zhang f74526341d Handle file boundaries when timestamps should not be persisted (#11578)
Summary:
Handle file boundaries `FileMetaData.smallest`, `FileMetaData.largest` for when `persist_user_defined_timestamps` is false:
    1) on the manifest write path, the original user-defined timestamps in file boundaries are stripped. This stripping is done during `VersionEdit::Encode` to limit the effect of the stripping to only the persisted version of the file boundaries.
    2) on the manifest read path during DB open, a a min timestamp is padded to the file boundaries. Ideally, this padding should happen during `VersionEdit::Decode` so that all in memory file boundaries have a compatible user key format as the running user comparator. However, because the user-defined timestamp size information is not available at that time. This change is added to `VersionEditHandler::OnNonCfOperation`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11578

Test Plan:
```
make all check
./version_edit_test --gtest_filter="*EncodeDecodeNewFile4HandleFileBoundary*".
./db_with_timestamp_basic_test --gtest_filter="*HandleFileBoundariesTest*"
```

Reviewed By: pdillinger

Differential Revision: D47309399

Pulled By: jowlyzhang

fbshipit-source-id: 21b4d54d2089a62826b31d779094a39cb2bbbd51
2023-07-10 11:03:25 -07:00
Yu Zhang 7521478b43 Record the persist_user_defined_timestamps flag in manifest (#11515)
Summary:
Start to record the value of the flag `AdvancedColumnFamilyOptions.persist_user_defined_timestamps` in the Manifest and table properties for a SST file when it is created. And use the recorded flag when creating a table reader for the SST file. This flag's default value is true, it is only explicitly recorded if it's false.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11515

Test Plan:
```
make all check
./version_edit_test
```

Reviewed By: ltamasi

Differential Revision: D46920386

Pulled By: jowlyzhang

fbshipit-source-id: 075c20363d3d2cc1368422ecc805617ed135cc26
2023-06-21 21:49:01 -07:00
Hui Xiao 8f763bdeab Record and use the tail size to prefetch table tail (#11406)
Summary:
**Context:**
We prefetch the tail part of a SST file (i.e, the blocks after data blocks till the end of the file) during each SST file open in hope to prefetch all the stuff at once ahead of time for later read e.g, footer, meta index, filter/index etc. The existing approach to estimate the tail size to prefetch is through `TailPrefetchStats` heuristics introduced in https://github.com/facebook/rocksdb/pull/4156, which has caused small reads in unlucky case (e.g,  small read into the tail buffer during table open in thread 1 under the same BlockBasedTableFactory object can make thread 2's tail prefetching use a small size that it shouldn't) and is hard to debug.  Therefore we decide to record the exact tail size and use it directly  to prefetch tail of the SST instead of relying heuristics.

**Summary:**
- Obtain and record in manifest the tail size in `BlockBasedTableBuilder::Finish()`
   - For backward compatibility, we fall back to TailPrefetchStats and last to simple heuristics that the tail size is a linear portion of the file size - see PR conversation for more.
- Make`tail_start_offset` part of the table properties and deduct tail size to record in manifest for external files (e.g, file ingestion, import CF) and db repair (with no access to manifest).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11406

Test Plan:
1. New UT
2. db bench
Note: db bench on /tmp/ where direct read is supported is too slow to finish and the default pinning setting in db bench is not helpful to profile # sst read of Get. Therefore I hacked the following to obtain the following comparison.
```
 diff --git a/table/block_based/block_based_table_reader.cc b/table/block_based/block_based_table_reader.cc
index bd5669f0f..791484c1f 100644
 --- a/table/block_based/block_based_table_reader.cc
+++ b/table/block_based/block_based_table_reader.cc
@@ -838,7 +838,7 @@ Status BlockBasedTable::PrefetchTail(
                            &tail_prefetch_size);

   // Try file system prefetch
-  if (!file->use_direct_io() && !force_direct_prefetch) {
+  if (false && !file->use_direct_io() && !force_direct_prefetch) {
     if (!file->Prefetch(prefetch_off, prefetch_len, ro.rate_limiter_priority)
              .IsNotSupported()) {
       prefetch_buffer->reset(new FilePrefetchBuffer(
 diff --git a/tools/db_bench_tool.cc b/tools/db_bench_tool.cc
index ea40f5fa0..39a0ac385 100644
 --- a/tools/db_bench_tool.cc
+++ b/tools/db_bench_tool.cc
@@ -4191,6 +4191,8 @@ class Benchmark {
           std::shared_ptr<TableFactory>(NewCuckooTableFactory(table_options));
     } else {
       BlockBasedTableOptions block_based_options;
+      block_based_options.metadata_cache_options.partition_pinning =
+      PinningTier::kAll;
       block_based_options.checksum =
           static_cast<ChecksumType>(FLAGS_checksum_type);
       if (FLAGS_use_hash_search) {
```
Create DB
```
./db_bench --bloom_bits=3 --use_existing_db=1 --seed=1682546046158958 --partition_index_and_filters=1 --statistics=1 -db=/dev/shm/testdb/ -benchmarks=readrandom -key_size=3200 -value_size=512 -num=1000000 -write_buffer_size=6550000 -disable_auto_compactions=false -target_file_size_base=6550000 -compression_type=none
```
ReadRandom
```
./db_bench --bloom_bits=3 --use_existing_db=1 --seed=1682546046158958 --partition_index_and_filters=1 --statistics=1 -db=/dev/shm/testdb/ -benchmarks=readrandom -key_size=3200 -value_size=512 -num=1000000 -write_buffer_size=6550000 -disable_auto_compactions=false -target_file_size_base=6550000 -compression_type=none
```
(a) Existing (Use TailPrefetchStats for tail size + use seperate prefetch buffer in PartitionedFilter/IndexReader::CacheDependencies())
```
rocksdb.table.open.prefetch.tail.hit COUNT : 3395
rocksdb.sst.read.micros P50 : 5.655570 P95 : 9.931396 P99 : 14.845454 P100 : 585.000000 COUNT : 999905 SUM : 6590614
```

(b) This PR (Record tail size + use the same tail buffer in PartitionedFilter/IndexReader::CacheDependencies())
```
rocksdb.table.open.prefetch.tail.hit COUNT : 14257
rocksdb.sst.read.micros P50 : 5.173347 P95 : 9.015017 P99 : 12.912610 P100 : 228.000000 COUNT : 998547 SUM : 5976540
```

As we can see, we increase the prefetch tail hit count and decrease SST read count with this PR

3. Test backward compatibility by stepping through reading with post-PR code on a db generated pre-PR.

Reviewed By: pdillinger

Differential Revision: D45413346

Pulled By: hx235

fbshipit-source-id: 7d5e36a60a72477218f79905168d688452a4c064
2023-05-08 13:14:28 -07:00
Peter Dillinger 3cacd4b4ec Put Cache and CacheWrapper in new public header (#11192)
Summary:
The definition of the Cache class should not be needed by the vast majority of RocksDB users, so I think it is just distracting to include it in cache.h, which is primarily needed for configuring and creating caches. This change moves the class to a new header advanced_cache.h. It is just cut-and-paste except for modifying the class API comment.

In general, operations on shared_ptr<Cache> should continue to work when only a forward declaration of Cache is available, as long as all the Cache instances provided are already shared_ptr. See https://stackoverflow.com/a/17650101/454544

Also, the most common way to customize a Cache is by wrapping an existing implementation, so it makes sense to provide CacheWrapper in the public API. This was a cut-and-paste job except removing the implementation of Name() so that derived classes must provide it.

Intended follow-up: consolidate Release() into one function to reduce customization bugs / confusion

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11192

Test Plan: `make check`

Reviewed By: anand1976

Differential Revision: D43055487

Pulled By: pdillinger

fbshipit-source-id: 7b05492df35e0f30b581b4c24c579bc275b6d110
2023-02-09 12:12:02 -08:00
Changyu Bi 6a82b68788 Avoid counting extra range tombstone compensated size in AddRangeDels() (#11091)
Summary:
in `CompactionOutputs::AddRangeDels()`, range tombstones with the same start and end key but different sequence numbers all contribute to compensated range tombstone size. This PR removes this redundancy. This PR also includes a fix from https://github.com/facebook/rocksdb/issues/11067 where a range tombstone that is not within a file's range was being added to the file. This fixes an assertion failure for `icmp.Compare(start, end) <= 0` in VersionSet::ApproximateSize() when calculating compensated range tombstone size. Assertions and a comment/essay was added to reason that no such range tombstone will be added after this fix.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11091

Test Plan:
- Added unit tests
- Stress test with small key range: `python3 tools/db_crashtest.py blackbox --simple --max_key=100 --interval=600 --write_buffer_size=262144 --target_file_size_base=256 --max_bytes_for_level_base=262144 --block_size=128 --value_size_mult=33 --subcompactions=10`

Reviewed By: ajkr

Differential Revision: D42521588

Pulled By: cbi42

fbshipit-source-id: 5bda3fe38997995314e1f7592319af12b69bc4f8
2023-01-17 12:47:44 -08:00
Changyu Bi cc6f323705 Include estimated bytes deleted by range tombstones in compensated file size (#10734)
Summary:
compensate file sizes in compaction picking so files with range tombstones are preferred, such that they get compacted down earlier as they tend to delete a lot of data. This PR adds a `compensated_range_deletion_size` field in FileMeta that is computed during Flush/Compaction and persisted in MANIFEST. This value is added to `compensated_file_size` which will be used for compaction picking. Currently, for a file in level L, `compensated_range_deletion_size` is set to the estimated bytes deleted by range tombstone of this file in all levels > L. This helps to reduce space amp when data in older levels are covered by range tombstones in level L.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10734

Test Plan:
- Added unit tests.
- benchmark to check if the above definition `compensated_range_deletion_size` is reducing space amp as intended, without affecting write amp too much. The experiment set up favorable for this optimization: large range tombstone issued infrequently. Command used:
```
./db_bench -benchmarks=fillrandom,waitforcompaction,stats,levelstats -use_existing_db=false -avoid_flush_during_recovery=true -write_buffer_size=33554432 -level_compaction_dynamic_level_bytes=true -max_background_jobs=8 -max_bytes_for_level_base=134217728 -target_file_size_base=33554432 -writes_per_range_tombstone=500000 -range_tombstone_width=5000000 -num=50000000 -benchmark_write_rate_limit=8388608 -threads=16 -duration=1800 --max_num_range_tombstones=1000000000
```

In this experiment, each thread wrote 16 range tombstones over the duration of 30 minutes, each range tombstone has width 5M that is the 10% of the key space width. Results shows this PR generates a smaller DB size.

Compaction stats from this PR:
```
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      2/0   31.54 MB   0.5      0.0     0.0      0.0       8.4      8.4       0.0   1.0      0.0     63.4    135.56            110.94       544    0.249       0      0       0.0       0.0
  L4      3/0   96.55 MB   0.8     18.5     6.7     11.8      18.4      6.6       0.0   2.7     65.3     64.9    290.08            284.03       108    2.686    284M  1957K       0.0       0.0
  L5     15/0   404.41 MB   1.0     19.1     7.7     11.4      18.8      7.4       0.3   2.5     66.6     65.7    292.93            285.34       220    1.332    293M  3808K       0.0       0.0
  L6    143/0    4.12 GB   0.0     45.0     7.5     37.5      41.6      4.1       0.0   5.5     71.2     65.9    647.00            632.66       251    2.578    739M    47M       0.0       0.0
 Sum    163/0    4.64 GB   0.0     82.6    21.9     60.7      87.2     26.5       0.3  10.4     61.9     65.4   1365.58           1312.97      1123    1.216   1318M    52M       0.0       0.0
```

Compaction stats from main:
```
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   0.0      0.0     0.0      0.0       8.4      8.4       0.0   1.0      0.0     60.5    142.12            115.89       569    0.250       0      0       0.0       0.0
  L4      3/0   85.68 MB   1.0     17.7     6.8     10.9      17.6      6.7       0.0   2.6     62.7     62.3    289.05            281.79       112    2.581    272M  2309K       0.0       0.0
  L5     11/0   293.73 MB   1.0     18.8     7.5     11.2      18.5      7.2       0.5   2.5     64.9     63.9    296.07            288.50       220    1.346    288M  4365K       0.0       0.0
  L6    130/0    3.94 GB   0.0     51.5     7.6     43.9      47.9      3.9       0.0   6.3     67.2     62.4    784.95            765.92       258    3.042    848M    51M       0.0       0.0
 Sum    144/0    4.31 GB   0.0     88.0    21.9     66.0      92.3     26.3       0.5  11.0     59.6     62.5   1512.19           1452.09      1159    1.305   1409M    58M       0.0       0.0```

Reviewed By: ajkr

Differential Revision: D39834713

Pulled By: cbi42

fbshipit-source-id: fe9341040b8704a8fbb10cad5cf5c43e962c7e6b
2022-12-29 13:28:24 -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
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
Peter Dillinger 6de7081cf3 Always verify SST unique IDs on SST file open (#10532)
Summary:
Although we've been tracking SST unique IDs in the DB manifest
unconditionally, checking has been opt-in and with an extra pass at DB::Open
time. This changes the behavior of `verify_sst_unique_id_in_manifest` to
check unique ID against manifest every time an SST file is opened through
table cache (normal DB operations), replacing the explicit pass over files
at DB::Open time. This change also enables the option by default and
removes the "EXPERIMENTAL" designation.

One possible criticism is that the option no longer ensures the integrity
of a DB at Open time. This is far from an all-or-nothing issue. Verifying
the IDs of all SST files hardly ensures all the data in the DB is readable.
(VerifyChecksum is supposed to do that.) Also, with
max_open_files=-1 (default, extremely common), all SST files are
opened at DB::Open time anyway.

Implementation details:
* `VerifySstUniqueIdInManifest()` functions are the extra/explicit pass
that is now removed.
* Unit tests that manipulate/corrupt table properties have to opt out of
this check, because that corrupts the "actual" unique id. (And even for
testing we don't currently have a mechanism to set "no unique id"
in the in-memory file metadata for new files.)
* A lot of other unit test churn relates to (a) default checking on, and
(b) checking on SST open even without DB::Open (e.g. on flush)
* Use `FileMetaData` for more `TableCache` operations (in place of
`FileDescriptor`) so that we have access to the unique_id whenever
we might need to open an SST file. **There is the possibility of
performance impact because we can no longer use the more
localized `fd` part of an `FdWithKeyRange` but instead follow the
`file_metadata` pointer. However, this change (possible regression)
is only done for `GetMemoryUsageByTableReaders`.**
* Removed a completely unnecessary constructor overload of
`TableReaderOptions`

Possible follow-up:
* Verification only happens when opening through table cache. Are there
more places where this should happen?
* Improve error message when there is a file size mismatch vs. manifest
(FIXME added in the appropriate place).
* I'm not sure there's a justification for `FileDescriptor` to be distinct from
`FileMetaData`.
* I'm skeptical that `FdWithKeyRange` really still makes sense for
optimizing some data locality by duplicating some data in memory, but I
could be wrong.
* An unnecessary overload of NewTableReader was recently added, in
the public API nonetheless (though unusable there). It should be cleaned
up to put most things under `TableReaderOptions`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10532

Test Plan:
updated unit tests

Performance test showing no significant difference (just noise I think):
`./db_bench -benchmarks=readwhilewriting[-X10] -num=3000000 -disable_wal=1 -bloom_bits=8 -write_buffer_size=1000000 -target_file_size_base=1000000`
Before: readwhilewriting [AVG 10 runs] : 68702 (± 6932) ops/sec
After: readwhilewriting [AVG 10 runs] : 68239 (± 7198) ops/sec

Reviewed By: jay-zhuang

Differential Revision: D38765551

Pulled By: pdillinger

fbshipit-source-id: a827a708155f12344ab2a5c16e7701c7636da4c2
2022-09-07 22:52:42 -07:00
Yanqin Jin fbfcf5cbcd Remove unused fields from FileMetaData (temporarily) (#10443)
Summary:
FileMetaData::[min|max]_timestamp are not currently being used or
tracked by RocksDB, even when user-defined timestamp is enabled. Each of
them is a std::string which can occupy 32 bytes. Remove them for now.
They may be added back when we have a pressing need for them. When we do
add them back, consider store them in a more compact way, e.g. one
boolean flag and a byte array of size 16.

Per file min/max timestamp bounds are available as table properties.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10443

Test Plan: make check

Reviewed By: pdillinger

Differential Revision: D38292275

Pulled By: riversand963

fbshipit-source-id: 841dc4e855ad8f8481c80cb020603de9607c9c94
2022-08-01 17:56:13 -07:00
Bo Wang c073ed7601 Fix typo in comments and code (#10233)
Summary:
Fix typo in comments and code.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10233

Test Plan: Existing unit tests should pass.

Reviewed By: jay-zhuang, anand1976

Differential Revision: D37356702

Pulled By: gitbw95

fbshipit-source-id: 32c019adcc6dcc95a9882b38147a310091368e51
2022-06-22 15:45:21 -07:00
zczhu 30141461f9 Add basic kRoundRobin compaction policy (#10107)
Summary:
Add `kRoundRobin` as a compaction priority. The implementation is as follows.

- Define a cursor as the smallest Internal key in the successor of the selected file. Add `vector<InternalKey> compact_cursor_` into `VersionStorageInfo` where each element (`InternalKey`) in `compact_cursor_` represents a cursor. In round-robin compaction policy, we just need to select the first file (assuming files are sorted) and also has the smallest InternalKey larger than/equal to the cursor. After a file is chosen, we create a new `Fsize` vector which puts the selected file is placed at the first position in `temp`, the next cursor is then updated as the smallest InternalKey in successor of the selected file (the above logic is implemented in `SortFileByRoundRobin`).
- After a compaction succeeds, typically `InstallCompactionResults()`, we choose the next cursor for the input level and save it to `edit`. When calling `LogAndApply`, we save the next cursor with its level into some local variable and finally apply the change to `vstorage` in `SaveTo` function.
- Cursors are persist pair by pair (<level, InternalKey>) in `EncodeTo` so that they can be reconstructed when reopening. An empty cursor will not be encoded to MANIFEST

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10107

Test Plan: add unit test (`CompactionPriRoundRobin`) in `compaction_picker_test`, add `kRoundRobin` priority in `CompactionPriTest` from `db_compaction_test`, and add `PersistRoundRobinCompactCursor` in `db_compaction_test`

Reviewed By: ajkr

Differential Revision: D37316037

Pulled By: littlepig2013

fbshipit-source-id: 9f481748190ace416079139044e00df2968fb1ee
2022-06-21 11:56:53 -07:00
Hui Xiao d665afdbf3 Account memory of FileMetaData in global memory limit (#9924)
Summary:
**Context/Summary:**
As revealed by heap profiling, allocation of `FileMetaData` for [newly created file added to a Version](https://github.com/facebook/rocksdb/pull/9924/files#diff-a6aa385940793f95a2c5b39cc670bd440c4547fa54fd44622f756382d5e47e43R774) can consume significant heap memory. This PR is to account that toward our global memory limit based on block cache capacity.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9924

Test Plan:
- Previous `make check` verified there are only 2 places where the memory of  the allocated `FileMetaData` can be released
- New unit test `TEST_P(ChargeFileMetadataTestWithParam, Basic)`
- db bench (CPU cost of `charge_file_metadata` in write and compact)
   - **write micros/op: -0.24%** : `TEST_TMPDIR=/dev/shm/testdb ./db_bench -benchmarks=fillseq -db=$TEST_TMPDIR -charge_file_metadata=1 (remove this option for pre-PR) -disable_auto_compactions=1 -write_buffer_size=100000 -num=4000000 | egrep 'fillseq'`
   - **compact micros/op -0.87%** : `TEST_TMPDIR=/dev/shm/testdb ./db_bench -benchmarks=fillseq -db=$TEST_TMPDIR -charge_file_metadata=1 -disable_auto_compactions=1 -write_buffer_size=100000 -num=4000000 -numdistinct=1000 && ./db_bench -benchmarks=compact -db=$TEST_TMPDIR -use_existing_db=1 -charge_file_metadata=1 -disable_auto_compactions=1 | egrep 'compact'`

table 1 - write

#-run | (pre-PR) avg micros/op | std micros/op | (post-PR)  micros/op | std micros/op | change (%)
-- | -- | -- | -- | -- | --
10 | 3.9711 | 0.264408 | 3.9914 | 0.254563 | 0.5111933721
20 | 3.83905 | 0.0664488 | 3.8251 | 0.0695456 | -0.3633711465
40 | 3.86625 | 0.136669 | 3.8867 | 0.143765 | 0.5289363078
80 | 3.87828 | 0.119007 | 3.86791 | 0.115674 | **-0.2673865734**
160 | 3.87677 | 0.162231 | 3.86739 | 0.16663 | **-0.2419539978**

table 2 - compact

#-run | (pre-PR) avg micros/op | std micros/op | (post-PR)  micros/op | std micros/op | change (%)
-- | -- | -- | -- | -- | --
10 | 2,399,650.00 | 96,375.80 | 2,359,537.00 | 53,243.60 | -1.67
20 | 2,410,480.00 | 89,988.00 | 2,433,580.00 | 91,121.20 | 0.96
40 | 2.41E+06 | 121811 | 2.39E+06 | 131525 | **-0.96**
80 | 2.40E+06 | 134503 | 2.39E+06 | 108799 | **-0.78**

- stress test: `python3 tools/db_crashtest.py blackbox --charge_file_metadata=1  --cache_size=1` killed as normal

Reviewed By: ajkr

Differential Revision: D36055583

Pulled By: hx235

fbshipit-source-id: b60eab94707103cb1322cf815f05810ef0232625
2022-06-14 13:06:40 -07:00
Jay Zhuang c6d326d3d7 Track SST unique id in MANIFEST and verify (#9990)
Summary:
Start tracking SST unique id in MANIFEST, which is used to verify with
SST properties to make sure the SST file is not overwritten or
misplaced. A DB option `try_verify_sst_unique_id` is introduced to
enable/disable the verification, if enabled, it opens all SST files
during DB-open to read the unique_id from table properties (default is
false), so it's recommended to use it with `max_open_files = -1` to
pre-open the files.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9990

Test Plan: unittests, format-compatible test, mini-crash

Reviewed By: anand1976

Differential Revision: D36381863

Pulled By: jay-zhuang

fbshipit-source-id: 89ea2eb6b35ed3e80ead9c724eb096083eaba63f
2022-05-19 11:04:21 -07:00
Levi Tamasi db536ee045 Propagate errors from UpdateBoundaries (#9851)
Summary:
In `FileMetaData`, we keep track of the lowest-numbered blob file
referenced by the SST file in question for the purposes of BlobDB's
garbage collection in the `oldest_blob_file_number` field, which is
updated in `UpdateBoundaries`. However, with the current code,
`BlobIndex` decoding errors (or invalid blob file numbers) are swallowed
in this method. The patch changes this by propagating these errors
and failing the corresponding flush/compaction. (Note that since blob
references are generated by the BlobDB code and also parsed by
`CompactionIterator`, in reality this can only happen in the case of
memory corruption.)

This change necessitated updating some unit tests that involved
fake/corrupt `BlobIndex` objects. Some of these just used a dummy string like
`"blob_index"` as a placeholder; these were replaced with real `BlobIndex`es.
Some were relying on the earlier behavior to simulate corruption; these
were replaced with `SyncPoint`-based test code that corrupts a valid
blob reference at read time.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9851

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D35683671

Pulled By: ltamasi

fbshipit-source-id: f7387af9945c48e4d5c4cd864f1ba425c7ad51f6
2022-04-15 20:25:48 -07:00
Levi Tamasi 42e0751b3a Clean up VersionStorageInfo a bit (#9494)
Summary:
The patch does some cleanup in and around `VersionStorageInfo`:
* Renames the method `PrepareApply` to `PrepareAppend` in `Version`
to make it clear that it is to be called before appending the `Version` to
`VersionSet` (via `AppendVersion`), not before applying any `VersionEdit`s.
* Introduces a helper method `VersionStorageInfo::PrepareForVersionAppend`
(called by `Version::PrepareAppend`) that encapsulates the population of the
various derived data structures in `VersionStorageInfo`, and turns the
methods computing the derived structures (`UpdateNumNonEmptyLevels`,
`CalculateBaseBytes` etc.) into private helpers.
* Changes `Version::PrepareAppend` so it only calls `UpdateAccumulatedStats`
if the `update_stats` flag is set. (Earlier, this was checked by the callee.)
Related to this, it also moves the call to `ComputeCompensatedSizes` to
`VersionStorageInfo::PrepareForVersionAppend`.
* Updates and cleans up `version_builder_test`, `version_set_test`, and
`compaction_picker_test` so `PrepareForVersionAppend` is called anytime
a new `VersionStorageInfo` is set up or saved. This cleanup also involves
splitting `VersionStorageInfoTest.MaxBytesForLevelDynamic`
into multiple smaller test cases.
* Fixes up a bunch of comments that were outdated or just plain incorrect.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9494

Test Plan: Ran `make check` and the crash test script for a while.

Reviewed By: riversand963

Differential Revision: D33971666

Pulled By: ltamasi

fbshipit-source-id: fda52faac7783041126e4f8dec0fe01bdcadf65a
2022-02-04 08:19:20 -08:00
Andrew Kryczka b860a42158 Recover to exact latest seqno of data committed to MANIFEST (#9305)
Summary:
The LastSequence field in the MANIFEST file is the baseline seqno for a recovered DB. Recovering WAL entries might cause the recovered DB's seqno to advance above this baseline, but the recovered DB will never use a smaller seqno.

Before this PR, we were writing the DB's seqno at the time of LogAndApply() as the LastSequence value. This works in the sense that it is a large enough baseline for the recovered DB that it'll never overwrite any records in existing SST files. At the same time, it's arbitrarily larger than what's needed. This behavior comes from LevelDB, where there was no tracking of largest seqno in an SST file.

Now we know the largest seqno of newly written SST files, so we can write an exact value in LastSequence that actually reflects the largest seqno in any file referred to by the MANIFEST. This is primarily useful for correctness testing with unsynced data loss, where the recovered DB's seqno needs to indicate what records were recovered.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9305

Test Plan:
- https://github.com/facebook/rocksdb/issues/9338 adds crash-recovery correctness testing coverage for WAL disabled use cases
- https://github.com/facebook/rocksdb/issues/9357 will extend that testing to cover file ingestion
- Added assertion at end of LogAndApply() for `VersionSet::descriptor_last_sequence_` consistency with files
- Manually tested upgrade/downgrade compatibility with a custom crash test that randomly picks between a `db_stress` built with and without this PR (for old code it must run with `-disable_wal=0`)

Reviewed By: riversand963

Differential Revision: D33182770

Pulled By: ajkr

fbshipit-source-id: 0bfafaf685f347cc8cb0e1d62e0186340a738f7d
2022-01-05 16:02:21 -08:00
sdong 88875df821 File temperature information should be preserved when restart the DB (#9242)
Summary:
Fix a bug that causes file temperature not preserved after DB is restarted, or options.max_manifest_file_size is hit.
Also, pass temperature information to NewRandomAccessFile() to allow users to hack a solution where they don't preserve tiering information.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9242

Test Plan: Add a unit test that would fail without the fix.

Reviewed By: jay-zhuang

Differential Revision: D32818150

fbshipit-source-id: 36aa3f148c60107f7b8e9d65b63b039f9e1a1eec
2021-12-03 14:43:14 -08:00
slk 937fbcbddc Track per-SST user-defined timestamp information in MANIFEST (#9092)
Summary:
Track per-SST user-defined timestamp information in MANIFEST https://github.com/facebook/rocksdb/issues/8957

Rockdb has supported user-defined timestamp feature. Application can specify a timestamp
when writing each k-v pair. When data flush from memory to disk file called SST files, file
creation activity will commit to MANIFEST. This commit is for tracking timestamp info in the
MANIFEST for each file. The changes involved are as follows:
1) Track max/min timestamp in FileMetaData, and fix invoved codes.
2) Add NewFileCustomTag::kMinTimestamp and NewFileCustomTag::kMinTimestamp in
    NewFileCustomTag ( in the kNewFile4 part ), and support invoved codes such as
    VersionEdit Encode and Decode etc.
3) Add unit test code for VersionEdit EncodeDecodeNewFile4, and fix invoved test codes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9092

Reviewed By: ajkr, akankshamahajan15

Differential Revision: D32252323

Pulled By: riversand963

fbshipit-source-id: d2642898d6e3ad1fef0eb866b98045408bd4e162
2021-11-10 10:49:04 -08:00
sdong 0ed8cb666d Write file temperature information to manifest (#8284)
Summary:
As a part of tiered storage, writing tempeature information to manifest is needed so that after DB recovery, RocksDB still has the tiering information, to implement some further necessary functionalities.

Also fix some issues in simulated hybrid FS.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8284

Test Plan: Add a new unit test to validate that the information is indeed written and read back.

Reviewed By: zhichao-cao

Differential Revision: D28335801

fbshipit-source-id: 56aeb2e6ea090be0200181dd968c8a7278037def
2021-05-17 15:15:23 -07:00
storagezhang 711881bc25 Fix some typos in comments (#8066)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8066

Reviewed By: jay-zhuang

Differential Revision: D27280799

Pulled By: mrambacher

fbshipit-source-id: 68f91f5af4ffe0a84be581961bf9366887f47702
2021-03-25 21:18:08 -07:00
Levi Tamasi c696f27432 Accumulate blob file additions in VersionEdit during recovery (#7903)
Summary:
During recovery, RocksDB performs a kind of dummy flush; namely, entries
from the WAL are added to memtables, which then get written to SSTs and
blob files (if enabled) just like during a regular flush. Note that
multiple memtables might be flushed during recovery for the same column
family, for example, if the DB is reopened with a lower write buffer size,
and therefore, we need to make sure to collect all SST and blob file
additions. The patch fixes a bug in the earlier logic which resulted in
later blob file additions overwriting earlier ones.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7903

Test Plan: Added a unit test and ran `db_stress`.

Reviewed By: jay-zhuang

Differential Revision: D26110847

Pulled By: ltamasi

fbshipit-source-id: eddb50a608a88f54f3cec3a423de8235aba951fd
2021-01-27 18:46:15 -08:00
Levi Tamasi 2d37830e44 Make blob related VersionEdit tags unignorable (#7886)
Summary:
BlobFileAddition and BlobFileGarbage should not be in the ignorable tag
range, since if they are present in the MANIFEST, users cannot downgrade
to a RocksDB version that does not understand them without losing access
to the data in the blob files. The patch moves these two tags to the
unignorable range; this should still be safe at this point, since the
integrated BlobDB project is still work in progress and thus there
shouldn't be any ignorable BlobFileAddition/BlobFileGarbage tags out
there.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7886

Test Plan: `make check`

Reviewed By: cheng-chang

Differential Revision: D25980956

Pulled By: ltamasi

fbshipit-source-id: 13cf5bd61d77f049b513ecd5ad0be8c637e40a9d
2021-01-20 20:29:04 -08:00
Cheng Chang e44948295e Make it able to ignore WAL related VersionEdits in older versions (#7873)
Summary:
Although the tags for `WalAddition`, `WalDeletion` are after `kTagSafeIgnoreMask`, to actually be able to skip these entries in older versions of RocksDB, we require that they are encoded with their encoded size as the prefix. This requirement is not met in the current codebase, so a downgraded DB may fail to open if these entries exist in the MANIFEST.

If a DB wants to downgrade, and its MANIFEST contains `WalAddition` or `WalDeletion`, it can set `track_and_verify_wals_in_manifest` to `false`, then restart twice, then downgrade. On the first restart, a new MANIFEST will be created with a `WalDeletion` indicating that all previously tracked WALs are removed from MANIFEST. On the second restart, since there is  no tracked WALs in MANIFEST now, a new MANIFEST will be created with neither `WalAddition` nor `WalDeletion`. Then the DB can downgrade.

Tags for `BlobFileAddition`, `BlobFileGarbage` also have the same problem, but this PR focuses on solving the problem for WAL edits.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7873

Test Plan: Added a `VersionEditTest::IgnorableTags` unit test to verify all entries with tags larger than `kTagSafeIgnoreMask` can actually be skipped and won't affect parsing of other entries.

Reviewed By: ajkr

Differential Revision: D25935930

Pulled By: cheng-chang

fbshipit-source-id: 7a02fdba4311d6084328c14aed110a26d08c3efb
2021-01-19 19:27:53 -08:00
Yanqin Jin eee0af9af1 Add full_history_ts_low to column family (#7740)
Summary:
Following https://github.com/facebook/rocksdb/issues/7655 and https://github.com/facebook/rocksdb/issues/7657, this PR adds `full_history_ts_low_` to `ColumnFamilyData`.
`ColumnFamilyData::full_history_ts_low_` will be used to create `FlushJob` and `CompactionJob`.

`ColumnFamilyData::full_history_ts_low` is persisted to the MANIFEST file. An application can only
increase its value. Consider the following case:

>
> The database has a key at ts=950. `full_history_ts_low` is first set to 1000, and then a GC is triggered
> and cleans up all data older than 1000. If the application sets `full_history_ts_low` to 900 afterwards,
> and tries to read at ts=960, the key at 950 is not seen. From the perspective of the read, the result
> is hard to reason. For simplicity, we just do now allow decreasing full_history_ts_low for now.
>

During recovery, the value of `full_history_ts_low` is restored for each column family if applicable. Note that
version edits in the MANIFEST file for the same column family may have `full_history_ts_low` unsorted due
to the potential interleaving of `LogAndApply` calls. Only the max will be used to restore the state of the
column family.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7740

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D25296217

Pulled By: riversand963

fbshipit-source-id: 24acda1df8262cd7cfdc6ce7b0ec56438abe242a
2020-12-05 14:18:22 -08:00
Yanqin Jin 8b6b6aeb1a Refactor with VersionEditHandler (#6581)
Summary:
Added a few classes in the same class hierarchy to remove code duplication and
refactor the logic of reading and processing MANIFEST files.

New classes are as follows.
```
class VersionEditHandlerBase;
class ListColumnFamiliesHandler : VersionEditHandlerBase;
class FileChecksumRetriever : VersionEditHandlerBase;
class DumpManifestHandler : VersionEditHandler;
```
Classes that already existed before this PR are as follows.
```
class VersionEditHandler : VersionEditHandlerBase;
```

With these classes, refactored functions: `VersionSet::Recover()`,
`VersionSet::ListColumnFamilies()`, `VersionSet::DumpManifest()`,
`GetFileChecksumFromManifest()`.

Test Plan (devserver):
```
make check
COMPILE_WITH_ASAN=1 make check
```
These refactored code, especially recovery-related logic, will be tested intensively by
all existing unit tests and stress tests. For example, run
```
make crash_test
```
Verified 3 successful runs on devserver.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/6581

Reviewed By: ajkr

Differential Revision: D20616217

Pulled By: riversand963

fbshipit-source-id: 048c7743aa4be2623ccd0cc3e61c0027e604e78b
2020-11-11 08:00:14 -08:00
Cheng Chang 1e40696dd1 Track WAL in MANIFEST: LogAndApply WAL events to MANIFEST (#7601)
Summary:
When a WAL is synced, an edit is written to MANIFEST.
After flushing memtables, the obsoleted WALs are piggybacked to MANIFEST while writing the new L0 files to MANIFEST.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7601

Test Plan:
`track_and_verify_wals_in_manifest` is enabled by default for all tests extending `DBBasicTest`, and in db_stress_test.
Unit test `wal_edit_test`, `version_edit_test`, and `version_set_test` are also updated.
Watch all tests to pass.

Reviewed By: ltamasi

Differential Revision: D24553957

Pulled By: cheng-chang

fbshipit-source-id: 66a569ff1bdced38e22900bd240b73113906e040
2020-11-06 17:22:36 -08:00
Cheng Chang 1b224324b5 Track WAL in MANIFEST: persist WALs to and recover WALs from MANIFEST (#7256)
Summary:
This PR makes it able to `LogAndApply` `VersionEdit`s related to WALs, and also be able to `Recover` from MANIFEST with WAL related `VersionEdit`s.

The `VersionEdit`s related to WAL are treated similarly as those related to column family operations, they are not applied to versions, but can be in a commit group. Mixing WAL related `VersionEdit`s with other types of edits will make logic in `ProcessManifestWrite` more complicated, so `VersionEdit`s related to WAL can either be WAL additions or deletions, like column family add and drop.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7256

Test Plan: a set of unit tests are added in `version_set_test.cc`

Reviewed By: riversand963

Differential Revision: D23123238

Pulled By: cheng-chang

fbshipit-source-id: 246be2ed4744fd03fa2738aba408aaa611d0379c
2020-10-23 22:49:51 -07:00
Levi Tamasi b0e7834100 Integrate blob file writing with the flush logic (#7345)
Summary:
The patch adds support for writing blob files during flush by integrating
`BlobFileBuilder` with the flush logic, most importantly, `BuildTable` and
`CompactionIterator`. If `enable_blob_files` is set, large values are extracted
to blob files and replaced with references. The resulting blob files are then
logged to the MANIFEST as part of the flush job's `VersionEdit` and
added to the `Version`, similarly to table files. Errors related to writing
blob files fail the flush, and any blob files written by such jobs are immediately
deleted (again, similarly to how SST files are handled). In addition, the patch
extends the logging and statistics around flushes to account for the presence
of blob files (e.g. `InternalStats::CompactionStats::bytes_written`, which is
used for calculating write amplification, now considers the blob files as well).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7345

Test Plan: Tested using `make check` and `db_bench`.

Reviewed By: riversand963

Differential Revision: D23506369

Pulled By: ltamasi

fbshipit-source-id: 646885f22dfbe063f650d38a1fedc132f499a159
2020-09-14 21:11:43 -07:00
Zitan Chen b578ca2e4d BackupEngine supports custom file checksums (#7085)
Summary:
A new option `std::shared_ptr<FileChecksumGenFactory> backup_checksum_gen_factory` is added to `BackupableDBOptions`. This allows custom checksum functions to be used for creating, verifying, or restoring backups.

Tests are added.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7085

Test Plan: Passed make check

Reviewed By: pdillinger

Differential Revision: D22390756

Pulled By: gg814

fbshipit-source-id: 3b7756ca444c2129844536b91c3ca09f53b6248f
2020-08-12 13:31:09 -07:00
Cheng Chang cd48ecaa1a Define WAL related classes to be used in VersionEdit and VersionSet (#7164)
Summary:
`WalAddition`, `WalDeletion` are defined in `wal_version.h` and used in `VersionEdit`.
`WalAddition` is used to represent events of creating a new WAL (no size, just log number), or closing a WAL (with size).
`WalDeletion` is used to represent events of deleting or archiving a WAL, it means the WAL is no longer alive (won't be replayed during recovery).

`WalSet` is the set of alive WALs kept in `VersionSet`.

1. Why use `WalDeletion` instead of relying on `MinLogNumber` to identify outdated WALs

On recovery, we can compute `MinLogNumber()` based on the log numbers kept in MANIFEST, any log with number < MinLogNumber can be ignored. So it seems that we don't need to persist `WalDeletion` to MANIFEST, since we can ignore the WALs based on MinLogNumber.

But the `MinLogNumber()` is actually a lower bound, it does not exactly mean that logs starting from MinLogNumber must exist. This is because in a corner case, when a column family is empty and never flushed, its log number is set to the largest log number, but not persisted in MANIFEST. So let's say there are 2 column families, when creating the DB, the first WAL has log number 1, so it's persisted to MANIFEST for both column families. Then CF 0 is empty and never flushed, CF 1 is updated and flushed, so a new WAL with log number 2 is created and persisted to MANIFEST for CF 1. But CF 0's log number in MANIFEST is still 1. So on recovery, MinLogNumber is 1, but since log 1 only contains data for CF 1, and CF 1 is flushed, log 1 might have already been deleted from disk.

We can make `MinLogNumber()` be the exactly minimum log number that must exist, by persisting the most recent log number for empty column families that are not flushed. But if there are N such column families, then every time a new WAL is created, we need to add N records to MANIFEST.

In current design, a record is persisted to MANIFEST only when WAL is created, closed, or deleted/archived, so the number of WAL related records are bounded to 3x number of WALs.

2. Why keep `WalSet` in `VersionSet` instead of applying the `VersionEdit`s to `VersionStorageInfo`

`VersionEdit`s are originally designed to track the addition and deletion of SST files. The SST files are related to column families, each column family has a list of `Version`s, and each `Version` keeps the set of active SST files in `VersionStorageInfo`.

But WALs are a concept of DB, they are not bounded to specific column families. So logically it does not make sense to store WALs in a column family's `Version`s.
Also, `Version`'s purpose is to keep reference to SST / blob files, so that they are not deleted until there is no version referencing them. But a WAL is deleted regardless of version references.
So we keep the WALs in `VersionSet`  for the purpose of writing out the DB state's snapshot when creating new MANIFESTs.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7164

Test Plan:
make version_edit_test && ./version_edit_test
make wal_edit_test && ./wal_edit_test

Reviewed By: ltamasi

Differential Revision: D22677936

Pulled By: cheng-chang

fbshipit-source-id: 5a3b6890140e572ffd79eb37e6e4c3c32361a859
2020-08-05 16:34:38 -07:00
Yanqin Jin 3020df9df5 Remove unnecessary inclusion of version_edit.h in env (#6952)
Summary:
In db_options.c, we should avoid including header files in the `db` directory to avoid introducing unnecessary dependency. The reason why `version_edit.h` has been included in `db_options.cc` is because we need two constants, `kUnknownChecksum` and `kUnknownChecksumFuncName`. We can put these two constants as `constexpr` in the public header `file_checksum.h`.

Test plan (devserver):
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6952

Reviewed By: zhichao-cao

Differential Revision: D21925341

Pulled By: riversand963

fbshipit-source-id: 2902f3b74c97f0cf16c58ad24c095c787c3a40e2
2020-06-07 21:56:55 -07:00
Zhichao Cao 5c6346c420 Revert "Added the safe-to-ignore tag to version_edit (#6530)" (#6569)
Summary:
This reverts commit e10553f2a6.

Pass make asan_check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6569

Reviewed By: riversand963

Differential Revision: D20574319

Pulled By: zhichao-cao

fbshipit-source-id: ce36981a21596f5f2e14da6a59a2bb3619509a8b
2020-03-23 10:27:47 -07:00
Yanqin Jin fb09ef05dc Attempt to recover from db with missing table files (#6334)
Summary:
There are situations when RocksDB tries to recover, but the db is in an inconsistent state due to SST files referenced in the MANIFEST being missing. In this case, previous RocksDB will just fail the recovery and return a non-ok status.
This PR enables another possibility. During recovery, RocksDB checks possible MANIFEST files, and try to recover to the most recent state without missing table file. `VersionSet::Recover()` applies version edits incrementally and "materializes" a version only when this version does not reference any missing table file. After processing the entire MANIFEST, the version created last will be the latest version.
`DBImpl::Recover()` calls `VersionSet::Recover()`. Afterwards, WAL replay will *not* be performed.
To use this capability, set `options.best_efforts_recovery = true` when opening the db. Best-efforts recovery is currently incompatible with atomic flush.

Test plan (on devserver):
```
$make check
$COMPILE_WITH_ASAN=1 make all && make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6334

Reviewed By: anand1976

Differential Revision: D19778960

Pulled By: riversand963

fbshipit-source-id: c27ea80f29bc952e7d3311ecf5ee9c54393b40a8
2020-03-20 19:30:48 -07:00
Zhichao Cao e10553f2a6 Added the safe-to-ignore tag to version_edit (#6530)
Summary:
Each time RocksDB switches to a new MANIFEST file from old one, it calls WriteCurrentStateToManifest() which writes a 'snapshot' of the current in-memory state of versions to the beginning of the new manifest as a bunch of version edits. We can distinguish these version edits from other version edits written during normal operations with a custom, safe-to-ignore tag.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6530

Test Plan: added test to version_edit_test, pass make asan_check

Reviewed By: riversand963

Differential Revision: D20524516

Pulled By: zhichao-cao

fbshipit-source-id: f1de102f5499bfa88dae3caa2f32c7f42cf904db
2020-03-19 11:30:26 -07:00
Levi Tamasi c15e85bdcb Move BlobDB related files under db/ to db/blob/ (#6519)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/6519

Test Plan:
```
make all
make check
```

Differential Revision: D20400691

Pulled By: ltamasi

fbshipit-source-id: 20ef911cf1c2c92c7f71ef0b493f9be64f2eef94
2020-03-12 11:00:56 -07:00
Levi Tamasi f5bc3b99d5 Split BlobFileState into an immutable and a mutable part (#6502)
Summary:
It's never too soon to refactor something. The patch splits the recently
introduced (`VersionEdit` related) `BlobFileState` into two classes
`BlobFileAddition` and `BlobFileGarbage`. The idea is that once blob files
are closed, they are immutable, and the only thing that changes is the
amount of garbage in them. In the new design, `BlobFileAddition` contains
the immutable attributes (currently, the count and total size of all blobs, checksum
method, and checksum value), while `BlobFileGarbage` contains the mutable
GC-related information elements (count and total size of garbage blobs). This is a
better fit for the GC logic and is more consistent with how SST files are handled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6502

Test Plan: `make check`

Differential Revision: D20348352

Pulled By: ltamasi

fbshipit-source-id: ff93f0121e80ab15e0e0a6525ba0d6af16a0e008
2020-03-10 17:27:26 -07:00
Levi Tamasi d87c10c6ab Add blob file state to VersionEdit (#6416)
Summary:
BlobDB currently does not keep track of blob files: no records are written to
the manifest when a blob file is added or removed, and upon opening a database,
the list of blob files is populated simply based on the contents of the blob directory.
This means that lost blob files cannot be detected at the moment. We plan to solve
this issue by making blob files a part of `Version`; as a first step, this patch makes
it possible to store information about blob files in `VersionEdit`. Currently, this information
includes blob file number, total number and size of all blobs, and total number and size
of garbage blobs. However, the format is extensible: new fields can be added in
both a forward compatible and a forward incompatible manner if needed (similarly
to `kNewFile4`).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6416

Test Plan: `make check`

Differential Revision: D19894234

Pulled By: ltamasi

fbshipit-source-id: f9753e1f2aedf6dadb70c09b345207cb9c58c329
2020-02-24 18:39:53 -08:00
sdong fdf882ded2 Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433)
Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433

Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.

Differential Revision: D19977691

fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
2020-02-20 12:09:57 -08:00
Zhichao Cao 4369f2c7bb Checksum for each SST file and stores in MANIFEST (#6216)
Summary:
In the current code base, RocksDB generate the checksum for each block and verify the checksum at usage. Current PR enable SST file checksum. After a SST file is generated by Flush or Compaction, RocksDB generate the SST file checksum and store the checksum value and checksum method name in the vs_info and MANIFEST as part for the FileMetadata.

Added the enable_sst_file_checksum to Options to enable or disable file checksum. Added sst_file_checksum to Options such that user can plugin their own SST file checksum calculate method via overriding the SstFileChecksum class. The checksum information inlcuding uint32_t checksum value and a checksum name (string).  A new tool is added to LDB such that user can dump out a list of file checksum information from MANIFEST. If user enables the file checksum but does not provide the sst_file_checksum instance, RocksDB will use the default crc32checksum implemented in table/sst_file_checksum_crc32c.h
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6216

Test Plan: Added the testing case in table_test and ldb_cmd_test to verify checksum is correct in different level. Pass make asan_check.

Differential Revision: D19171461

Pulled By: zhichao-cao

fbshipit-source-id: b2e53479eefc5bb0437189eaa1941670e5ba8b87
2020-02-10 15:52:52 -08:00
Levi Tamasi 752c87af78 Clean up VersionEdit a bit (#6383)
Summary:
This is a bunch of small improvements to `VersionEdit`. Namely, the patch

* Makes the names and order of variables, methods, and code chunks related
  to the various information elements more consistent, and adds missing
  getters for the sake of completeness.
* Initializes previously uninitialized stack variables.
* Marks all getters const to improve const correctness.
* Adds in-class initializers and removes the default ctor that would
  create an object with uninitialized built-in fields and call `Clear`
  afterwards.
* Adds a new type alias for new files and changes the existing `typedef`
  for deleted files into a type alias as well.
* Makes the helper method `DecodeNewFile4From` private.
* Switches from long-winded iterator syntax to range based loops in a
  couple of places.
* Fixes a couple of assignments where an integer 0 was assigned to
  boolean members.
* Fixes a getter which used to return a `const std::string` instead of
the intended `const std::string&`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6383

Test Plan: make check

Differential Revision: D19780537

Pulled By: ltamasi

fbshipit-source-id: b0b4f09fee0ec0e7c7b7a6d76bfe5346e91824d0
2020-02-07 13:27:06 -08:00
sdong aa1857e2df Support options.max_open_files = -1 with periodic_compaction_seconds (#6090)
Summary:
options.periodic_compaction_seconds isn't supported when options.max_open_files != -1. It's because that the information of file creation time is stored in table properties and are not guaranteed to be loaded unless options.max_open_files = -1. Relax this constraint by storing the information in manifest.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6090

Test Plan: Pass all existing tests; Modify an existing test to force the manifest value to take 0 to simulate backward compatibility case; manually open the DB generated with the change by release 4.2.

Differential Revision: D18702268

fbshipit-source-id: 13e0bd94f546498a04f3dc5fc0d9dff5125ec9eb
2019-11-26 21:39:56 -08:00
sdong d8c28e692a Support options.ttl with options.max_open_files = -1 (#6060)
Summary:
Previously, options.ttl cannot be set with options.max_open_files = -1, because it makes use of creation_time field in table properties, which is not available unless max_open_files = -1. With this commit, the information will be stored in manifest and when it is available, will be used instead.

Note that, this change will break forward compatibility for release 5.1 and older.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6060

Test Plan: Extend existing test case to options.max_open_files != -1, and simulate backward compatility in one test case by forcing the value to be 0.

Differential Revision: D18631623

fbshipit-source-id: 30c232a8672de5432ce9608bb2488ecc19138830
2019-11-22 21:23:00 -08:00
Levi Tamasi 5f025ea832 BlobDB GC: add SST <-> oldest blob file referenced mapping (#5903)
Summary:
This is groundwork for adding garbage collection support to BlobDB. The
patch adds logic that keeps track of the oldest blob file referred to by
each SST file. The oldest blob file is identified during flush/
compaction (similarly to how the range of keys covered by the SST is
identified), and persisted in the manifest as a custom field of the new
file edit record. Blob indexes with TTL are ignored for the purposes of
identifying the oldest blob file (since such blob files are cleaned up by the
TTL logic in BlobDB).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5903

Test Plan:
Added new unit tests; also ran db_bench in BlobDB mode, inspected the
manifest using ldb, and confirmed (by scanning the SST files using
sst_dump) that the value of the oldest blob file number field matches
the contents of the file for each SST.

Differential Revision: D17859997

Pulled By: ltamasi

fbshipit-source-id: 21662c137c6259a6af70446faaf3a9912c550e90
2019-10-14 15:21:01 -07:00