mirror of https://github.com/facebook/rocksdb.git
992 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Hui Xiao
|
632746bb5b |
Improve DBTest.DynamicLevelCompressionPerLevel (#13044)
Summary: **Context/Summary:** A part of this test is to verify compression conditionally happens depending on the shape of the LSM when `options.level_compaction_dynamic_level_bytes = true;`. It uses the total file size to determine whether compression has happened or not. This involves some hard-coded math hard to understand. This PR replaces those with statistics that directly shows whether compression has happened or not. Pull Request resolved: https://github.com/facebook/rocksdb/pull/13044 Test Plan: Existing test Reviewed By: jaykorean Differential Revision: D63666361 Pulled By: hx235 fbshipit-source-id: 8c9b1bea9b06ff1e3ed95c576aec6705159af137 |
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Peter Dillinger
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dd23e84cad |
Re-implement GetApproximateMemTableStats for skip lists (#13047)
Summary: GetApproximateMemTableStats() could return some bad results with the standard skip list memtable. See this new db_bench test showing the dismal distribution of results when the actual number of entries in range is 1000: ``` $ ./db_bench --benchmarks=filluniquerandom,approximatememtablestats,readrandom --value_size=1 --num=1000000 --batch_size=1000 ... filluniquerandom : 1.391 micros/op 718915 ops/sec 1.391 seconds 1000000 operations; 11.7 MB/s approximatememtablestats : 3.711 micros/op 269492 ops/sec 3.711 seconds 1000000 operations; Reported entry count stats (expected 1000): Count: 1000000 Average: 2344.1611 StdDev: 26587.27 Min: 0 Median: 965.8555 Max: 835273 Percentiles: P50: 965.86 P75: 1610.77 P99: 12618.01 P99.9: 74991.58 P99.99: 830970.97 ------------------------------------------------------ [ 0, 1 ] 131344 13.134% 13.134% ### ( 1, 2 ] 115 0.011% 13.146% ( 2, 3 ] 106 0.011% 13.157% ( 3, 4 ] 190 0.019% 13.176% ( 4, 6 ] 214 0.021% 13.197% ( 6, 10 ] 522 0.052% 13.249% ( 10, 15 ] 748 0.075% 13.324% ( 15, 22 ] 1002 0.100% 13.424% ( 22, 34 ] 1948 0.195% 13.619% ( 34, 51 ] 3067 0.307% 13.926% ( 51, 76 ] 4213 0.421% 14.347% ( 76, 110 ] 5721 0.572% 14.919% ( 110, 170 ] 11375 1.137% 16.056% ( 170, 250 ] 17928 1.793% 17.849% ( 250, 380 ] 36597 3.660% 21.509% # ( 380, 580 ] 77882 7.788% 29.297% ## ( 580, 870 ] 160193 16.019% 45.317% ### ( 870, 1300 ] 210098 21.010% 66.326% #### ( 1300, 1900 ] 167461 16.746% 83.072% ### ( 1900, 2900 ] 78678 7.868% 90.940% ## ( 2900, 4400 ] 47743 4.774% 95.715% # ( 4400, 6600 ] 17650 1.765% 97.480% ( 6600, 9900 ] 11895 1.190% 98.669% ( 9900, 14000 ] 4993 0.499% 99.168% ( 14000, 22000 ] 2384 0.238% 99.407% ( 22000, 33000 ] 1966 0.197% 99.603% ( 50000, 75000 ] 2968 0.297% 99.900% ( 570000, 860000 ] 999 0.100% 100.000% readrandom : 1.967 micros/op 508487 ops/sec 1.967 seconds 1000000 operations; 8.2 MB/s (1000000 of 1000000 found) ``` Perhaps the only good thing to say about the old implementation was that it was fast, though apparently not that fast. I've implemented a much more robust and reasonably fast new version of the function. It's still logarithmic but with some larger constant factors. The standard deviation from true count is around 20% or less, and roughly the CPU cost of two memtable point look-ups. See code comments for detail. ``` $ ./db_bench --benchmarks=filluniquerandom,approximatememtablestats,readrandom --value_size=1 --num=1000000 --batch_size=1000 ... filluniquerandom : 1.478 micros/op 676434 ops/sec 1.478 seconds 1000000 operations; 11.0 MB/s approximatememtablestats : 2.694 micros/op 371157 ops/sec 2.694 seconds 1000000 operations; Reported entry count stats (expected 1000): Count: 1000000 Average: 1073.5158 StdDev: 197.80 Min: 608 Median: 1079.9506 Max: 2176 Percentiles: P50: 1079.95 P75: 1223.69 P99: 1852.36 P99.9: 1898.70 P99.99: 2176.00 ------------------------------------------------------ ( 580, 870 ] 134848 13.485% 13.485% ### ( 870, 1300 ] 747868 74.787% 88.272% ############### ( 1300, 1900 ] 116536 11.654% 99.925% ## ( 1900, 2900 ] 748 0.075% 100.000% readrandom : 1.997 micros/op 500654 ops/sec 1.997 seconds 1000000 operations; 8.1 MB/s (1000000 of 1000000 found) ``` We can already see that the distribution of results is dramatically better and wonderfully normal-looking, with relative standard deviation around 20%. The function is also FASTER, at least with these parameters. Let's look how this behavior generalizes, first *much* larger range: ``` $ ./db_bench --benchmarks=filluniquerandom,approximatememtablestats,readrandom --value_size=1 --num=1000000 --batch_size=30000 filluniquerandom : 1.390 micros/op 719654 ops/sec 1.376 seconds 990000 operations; 11.7 MB/s approximatememtablestats : 1.129 micros/op 885649 ops/sec 1.129 seconds 1000000 operations; Reported entry count stats (expected 30000): Count: 1000000 Average: 31098.8795 StdDev: 3601.47 Min: 21504 Median: 29333.9303 Max: 43008 Percentiles: P50: 29333.93 P75: 33018.00 P99: 43008.00 P99.9: 43008.00 P99.99: 43008.00 ------------------------------------------------------ ( 14000, 22000 ] 408 0.041% 0.041% ( 22000, 33000 ] 749327 74.933% 74.974% ############### ( 33000, 50000 ] 250265 25.027% 100.000% ##### readrandom : 1.894 micros/op 528083 ops/sec 1.894 seconds 1000000 operations; 8.5 MB/s (989989 of 1000000 found) ``` This is *even faster* and relatively *more accurate*, with relative standard deviation closer to 10%. Code comments explain why. Now let's look at smaller ranges. Implementation quirks or conveniences: * When actual number in range is >= 40, the minimum return value is 40. * When the actual is <= 10, it is guaranteed to return that actual number. ``` $ ./db_bench --benchmarks=filluniquerandom,approximatememtablestats,readrandom --value_size=1 --num=1000000 --batch_size=75 ... filluniquerandom : 1.417 micros/op 705668 ops/sec 1.417 seconds 999975 operations; 11.4 MB/s approximatememtablestats : 3.342 micros/op 299197 ops/sec 3.342 seconds 1000000 operations; Reported entry count stats (expected 75): Count: 1000000 Average: 75.1210 StdDev: 15.02 Min: 40 Median: 71.9395 Max: 256 Percentiles: P50: 71.94 P75: 89.69 P99: 119.12 P99.9: 166.68 P99.99: 229.78 ------------------------------------------------------ ( 34, 51 ] 38867 3.887% 3.887% # ( 51, 76 ] 550554 55.055% 58.942% ########### ( 76, 110 ] 398854 39.885% 98.828% ######## ( 110, 170 ] 11353 1.135% 99.963% ( 170, 250 ] 364 0.036% 99.999% ( 250, 380 ] 8 0.001% 100.000% readrandom : 1.861 micros/op 537224 ops/sec 1.861 seconds 1000000 operations; 8.7 MB/s (999974 of 1000000 found) $ ./db_bench --benchmarks=filluniquerandom,approximatememtablestats,readrandom --value_size=1 --num=1000000 --batch_size=25 ... filluniquerandom : 1.501 micros/op 666283 ops/sec 1.501 seconds 1000000 operations; 10.8 MB/s approximatememtablestats : 5.118 micros/op 195401 ops/sec 5.118 seconds 1000000 operations; Reported entry count stats (expected 25): Count: 1000000 Average: 26.2392 StdDev: 4.58 Min: 25 Median: 28.4590 Max: 72 Percentiles: P50: 28.46 P75: 31.69 P99: 49.27 P99.9: 67.95 P99.99: 72.00 ------------------------------------------------------ ( 22, 34 ] 928936 92.894% 92.894% ################### ( 34, 51 ] 67960 6.796% 99.690% # ( 51, 76 ] 3104 0.310% 100.000% readrandom : 1.892 micros/op 528595 ops/sec 1.892 seconds 1000000 operations; 8.6 MB/s (1000000 of 1000000 found) $ ./db_bench --benchmarks=filluniquerandom,approximatememtablestats,readrandom --value_size=1 --num=1000000 --batch_size=10 ... filluniquerandom : 1.642 micros/op 608916 ops/sec 1.642 seconds 1000000 operations; 9.9 MB/s approximatememtablestats : 3.042 micros/op 328721 ops/sec 3.042 seconds 1000000 operations; Reported entry count stats (expected 10): Count: 1000000 Average: 10.0000 StdDev: 0.00 Min: 10 Median: 10.0000 Max: 10 Percentiles: P50: 10.00 P75: 10.00 P99: 10.00 P99.9: 10.00 P99.99: 10.00 ------------------------------------------------------ ( 6, 10 ] 1000000 100.000% 100.000% #################### readrandom : 1.805 micros/op 554126 ops/sec 1.805 seconds 1000000 operations; 9.0 MB/s (1000000 of 1000000 found) ``` Remarkably consistent. Pull Request resolved: https://github.com/facebook/rocksdb/pull/13047 Test Plan: new db_bench test for both performance and accuracy (see above); added to crash test; unit test updated. Reviewed By: cbi42 Differential Revision: D63722003 Pulled By: pdillinger fbshipit-source-id: cfc8613c085e87c17ecec22d82601aac2a5a1b26 |
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Peter Dillinger
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21eb82ebec |
Disable "uncache" behavior in DB shutdown (#12751)
Summary: Crash test showed a potential use-after-free where a file marked as obsolete and eligible for uncache on destruction is destroyed in the VersionSet destructor, which only happens as part of DB shutdown. At that point, the in-memory column families have already been destroyed, so attempting to uncache could use-after-free on stuff like getting the `user_comparator()` from the `internal_comparator()`. I attempted to make it smarter, but wasn't able to untangle the destruction dependencies in a way that was safe, understandable, and maintainable. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12751 Test Plan: Reproduced by adding uncache_aggressiveness to an existing (but otherwise unrelated) test. This makes it a fair regression test. Also added testing to ensure that trivial moves and DB close & reopen are well behaved with uncache_aggressiveness. Specifically, this issue doesn't seem to be because things are uncached inappropriately in those cases. Reviewed By: ltamasi Differential Revision: D58390058 Pulled By: pdillinger fbshipit-source-id: 66ac9cb13bf02638fa80ee5b7218153d8bc7cfd3 |
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Changyu Bi
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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 |
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Changyu Bi
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ffd7930312 |
Add more debug print to `DBTestWithParam.ThreadStatusSingleCompaction` (#12661)
Summary:
This test is flaky and a recent failure prints the following:
```
[ RUN ] DBTestWithParam/DBTestWithParam.ThreadStatusSingleCompaction/0
thread id: 1842811, thread status:
thread id: 1842803, thread status:
db/db_test.cc:4697: Failure
Expected equality of these values:
op_count
Which is: 0
expected_count
Which is: 1
[ FAILED ] DBTestWithParam/DBTestWithParam.ThreadStatusSingleCompaction/0, where GetParam() = (1, false) (307 ms)
```
Empty thread status implies that operation_type of the threads are all OP_UNKNOWN. From
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Changyu Bi
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5bf2c00a35 |
Clarify manual compaction and file ingestion behavior with FIFO compaction (#12618)
Summary:
For manual compaction, FIFO compaction will always skip key range overlapping checking with SST files. If CompactRange() is called with CompactionRangeOptions::change_level=true, a CF with FIFO compaction will now return Status::NotSupported.
For file ingestion, we will always ingest into L0. Previously, it's possible to ingest files into non-L0 levels with FIFO compaction.
These changes also help to fix [this](
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Jay Huh
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d34712e0ac |
MultiCfIterator - AttributeGroupIter Impl & CoalescingIter Optimization (#12534)
Summary: Continuing from the previous MultiCfIterator Implementations - (https://github.com/facebook/rocksdb/issues/12422, https://github.com/facebook/rocksdb/issues/12480 #12465), this PR completes the `AttributeGroupIterator` by implementing `AttributeGroupIteratorImpl::AddToAttributeGroups()`. While implementing the `AttributeGroupIterator`, we had to make some changes in `MultiCfIteratorImpl` and found an opportunity to improve `Coalesce()` in `CoalescingIterator`. Lifting `UNDER CONSTRUCTION - DO NOT USE` comment by replacing it with `EXPERIMENTAL` Here are some implementation details: - `IteratorAttributeGroups` is introduced to avoid having to copy all `WideColumn` objects during iteration. - `PopulateIterator()` no longer advances non-top iterators that have the same key as the top iterator in the heap. - `AdvanceIterator()` needs to advance the non-top iterators when they have the same key as the top iterator in the heap. - Instead of populating one by one, `PopulateIterator()` now collects all items with the same key and calls `populate_func(items)` at once. - This allowed optimization in `Coalesce()` such that we no longer do K-1 rounds of 2-way merge, but do one K-way merge instead. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12534 Test Plan: Uncommented the assertions in `verifyAttributeGroupIterator()` ``` ./multi_cf_iterator_test ``` Reviewed By: ltamasi Differential Revision: D56089019 Pulled By: jaykorean fbshipit-source-id: 6b0b4247e221f69b40b147d41492008cc9b15054 |
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Jay Huh
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58a98bded9 |
MultiCFIterator Refactor - CoalescingIterator & AttributeGroupIterator (#12480)
Summary:
There are a couple of reasons to modify the current implementation of the MultiCfIterator, which implements the generic `Iterator` interface.
- The default behavior of `value()`/`columns()` returning data from different Column Families for different keys can be prone to errors, even though there might be valid use cases where users do not care about the origin of the value/columns.
- The `attribute_groups()` API, which is not yet implemented, will not be useful for a single-CF iterator.
In this PR, we are implementing the following changes:
- `IteratorBase` introduced, which includes all basic iterator functions except `value()` and `columns()`.
- `Iterator`, which now inherits from `IteratorBase`, includes `value()` and `columns()`.
- New public interface `AttributeGroupIterator` inherits from `IteratorBase` and additionally includes `attribute_groups()` (to be implemented).
- Renamed former `MultiCfIterator` to `CoalescingIterator` which inherits from `Iterator`
- Existing MultiCfIteratorTest has been split into two - `CoalescingIteratorTest` and `AttributeGroupIteratorTest`.
- Moved AttributeGroup related code from `wide_columns.h` to a new file, `attribute_groups.h`.
Some Implementation Details
- `MultiCfIteratorImpl` takes two functions - `populate_func` and `reset_func` and use them to populate `value_` and `columns_` in CoalescingIterator and `attribute_groups_` in AttributeGroupIterator. In CoalescingIterator, populate_func is `Coalesce()`, in AttributeGroupIterator populate_func is `AddToAttributeGroups()`. `reset_func` clears populated value_, columns_ and attribute_groups_ accordingly.
- `Coalesce()` merge sorts columns from multiple CFs when a key exists in more than on CFs. column that appears in later CF overwrites the prior ones.
For example, if CF1 has `"key_1" ==> {"col_1": "foo", "col_2", "baz"}` and CF2 has `"key_1" ==> {"col_2": "quux", "col_3", "bla"}`, and when the iterator is at `key_1`, `columns()` will return `{"col_1": "foo", "col_2", "quux", "col_3", "bla"}`
In this example, `value()` will be empty, because none of them have values for `kDefaultColumnName`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12480
Test Plan:
## Unit Test
```
./multi_cf_iterator_test
```
## Performance Test
To make sure this change does not impact existing `Iterator` performance
**Build**
```
$> make -j64 release
```
**Setup**
```
$> TEST_TMPDIR=/dev/shm/db_bench ./db_bench -benchmarks="filluniquerandom" -key_size=32 -value_size=512 -num=1000000 -compression_type=none
```
**Run**
```
TEST_TMPDIR=/dev/shm/db_bench ./db_bench -use_existing_db=1 -benchmarks="newiterator,seekrandom" -cache_size=10485760000
```
**Before the change**
```
DB path: [/dev/shm/db_bench/dbbench]
newiterator : 0.519 micros/op 1927904 ops/sec 0.519 seconds 1000000 operations;
DB path: [/dev/shm/db_bench/dbbench]
seekrandom : 5.302 micros/op 188589 ops/sec 5.303 seconds 1000000 operations; (0 of 1000000 found)
```
**After the change**
```
DB path: [/dev/shm/db_bench/dbbench]
newiterator : 0.497 micros/op 2011012 ops/sec 0.497 seconds 1000000 operations;
DB path: [/dev/shm/db_bench/dbbench]
seekrandom : 5.252 micros/op 190405 ops/sec 5.252 seconds 1000000 operations; (0 of 1000000 found)
```
Reviewed By: ltamasi
Differential Revision: D55353909
Pulled By: jaykorean
fbshipit-source-id: 8d7786ffee09e022261ce34aa60e8633685e1946
|
|
|
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 |
|
|
Jay Huh
|
3412195367 |
Introduce MultiCfIterator (#12153)
Summary: This PR introduces a new implementation of `Iterator` via a new public API called `NewMultiCfIterator()`. The new API takes a vector of column family handles to build a cross-column-family iterator, which internally maintains multiple `DBIter`s as child iterators from a consistent database state. When a key exists in multiple column families, the iterator selects the value (and wide columns) from the first column family containing the key, following the order provided in the `column_families` parameter. Similar to the merging iterator, a min heap is used to iterate across the child iterators. Backward iteration and direction change functionalities will be implemented in future PRs. The comparator used to compare keys across different column families will be derived from the iterator of the first column family specified in `column_families`. This comparator will be checked against the comparators from all other column families that the iterator will traverse. If there's a mismatch with any of the comparators, the initialization of the iterator will fail. Please note that this PR is not enough for users to start using `MultiCfIterator`. The `MultiCfIterator` and related APIs are still marked as "**DO NOT USE - UNDER CONSTRUCTION**". This PR is just the first of many PRs that will follow soon. This PR includes the following: - Introduction and partial implementation of the `MultiCfIterator`, which implements the generic `Iterator` interface. The implementation includes the construction of the iterator, `SeekToFirst()`, `Next()`, `Valid()`, `key()`, `value()`, and `columns()`. - Unit tests to verify iteration across multiple column families in two distinct scenarios: (1) keys are unique across all column families, and (2) the same keys exist in multiple column families. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12153 Reviewed By: pdillinger Differential Revision: D52308697 Pulled By: jaykorean fbshipit-source-id: b03e69f13b40af5a8f0598d0f43a0bec01ef8294 |
|
|
anand76
|
d227276147 |
Deprecate some variants of Get and MultiGet (#12327)
Summary: A lot of variants of Get and MultiGet have been added to `include/rocksdb/db.h` over the years. Try to consolidate them by marking variants that don't return timestamps as deprecated. The underlying DB implementation will check and return Status::NotSupported() if it doesn't support returning timestamps and the caller asks for it. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12327 Reviewed By: pdillinger Differential Revision: D53828151 Pulled By: anand1976 fbshipit-source-id: e0b5ca42d32daa2739d5f439a729815a2d4ff050 |
|
|
Yu Zhang
|
4bea83aa44 |
Remove the force mode for EnableFileDeletions API (#12337)
Summary: There is no strong reason for user to need this mode while on the other hand, its behavior is destructive. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12337 Reviewed By: hx235 Differential Revision: D53630393 Pulled By: jowlyzhang fbshipit-source-id: ce94b537258102cd98f89aa4090025663664dd78 |
|
|
Peter Dillinger
|
54cb9c77d9 |
Prefer static_cast in place of most reinterpret_cast (#12308)
Summary: The following are risks associated with pointer-to-pointer reinterpret_cast: * Can produce the "wrong result" (crash or memory corruption). IIRC, in theory this can happen for any up-cast or down-cast for a non-standard-layout type, though in practice would only happen for multiple inheritance cases (where the base class pointer might be "inside" the derived object). We don't use multiple inheritance a lot, but we do. * Can mask useful compiler errors upon code change, including converting between unrelated pointer types that you are expecting to be related, and converting between pointer and scalar types unintentionally. I can only think of some obscure cases where static_cast could be troublesome when it compiles as a replacement: * Going through `void*` could plausibly cause unnecessary or broken pointer arithmetic. Suppose we have `struct Derived: public Base1, public Base2`. If we have `Derived*` -> `void*` -> `Base2*` -> `Derived*` through reinterpret casts, this could plausibly work (though technical UB) assuming the `Base2*` is not dereferenced. Changing to static cast could introduce breaking pointer arithmetic. * Unnecessary (but safe) pointer arithmetic could arise in a case like `Derived*` -> `Base2*` -> `Derived*` where before the Base2 pointer might not have been dereferenced. This could potentially affect performance. With some light scripting, I tried replacing pointer-to-pointer reinterpret_casts with static_cast and kept the cases that still compile. Most occurrences of reinterpret_cast have successfully been changed (except for java/ and third-party/). 294 changed, 257 remain. A couple of related interventions included here: * Previously Cache::Handle was not actually derived from in the implementations and just used as a `void*` stand-in with reinterpret_cast. Now there is a relationship to allow static_cast. In theory, this could introduce pointer arithmetic (as described above) but is unlikely without multiple inheritance AND non-empty Cache::Handle. * Remove some unnecessary casts to void* as this is allowed to be implicit (for better or worse). Most of the remaining reinterpret_casts are for converting to/from raw bytes of objects. We could consider better idioms for these patterns in follow-up work. I wish there were a way to implement a template variant of static_cast that would only compile if no pointer arithmetic is generated, but best I can tell, this is not possible. AFAIK the best you could do is a dynamic check that the void* conversion after the static cast is unchanged. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12308 Test Plan: existing tests, CI Reviewed By: ltamasi Differential Revision: D53204947 Pulled By: pdillinger fbshipit-source-id: 9de23e618263b0d5b9820f4e15966876888a16e2 |
|
|
Andrew Kryczka
|
f9d45358ca |
Removed `check_flush_compaction_key_order` (#12311)
Summary: `check_flush_compaction_key_order` option was introduced for the key order checking online validation. It gave users the ability to disable the validation without downgrade in case the validation caused inefficiencies or false positives. Over time this validation has shown to be cheap and correct, so the option to disable it can now be removed. Pull Request resolved: https://github.com/facebook/rocksdb/pull/12311 Reviewed By: cbi42 Differential Revision: D53233379 Pulled By: ajkr fbshipit-source-id: 1384361104021d6e3e580dce2ec123f9f99ce637 |
|
|
Peter Dillinger
|
76c834e441 |
Remove 'virtual' when implied by 'override' (#12319)
Summary:
... to follow modern C++ style / idioms.
Used this hack:
```
for FILE in `cat my_list_of_files`; do perl -pi -e 'BEGIN{undef $/;} s/ virtual( [^;{]* override)/$1/smg' $FILE; done
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/12319
Test Plan: existing tests, CI
Reviewed By: jaykorean
Differential Revision: D53275303
Pulled By: pdillinger
fbshipit-source-id: bc0881af270aa8ef4d0ae4f44c5a6614b6407377
|
|
|
Changyu Bi
|
3ef9092487 |
Print additional information when flaky test DBTestWithParam.ThreadStatusSingleCompaction fails (#12268)
Summary: The test is [flaky](https://github.com/facebook/rocksdb/actions/runs/7616272304/job/20742657041?pr=12257&fbclid=IwAR1vNI1rSRVKnOsXs0WCPklqTkBXxlwS1GMJgWWe7D8dtAvh6e6wxk067FY) but I could not reproduce the test failure. Add some debug print to make the next failure more helpful Pull Request resolved: https://github.com/facebook/rocksdb/pull/12268 Test Plan: ``` check print works when test fails: [ RUN ] DBTestWithParam/DBTestWithParam.ThreadStatusSingleCompaction/0 thread id: 6134067200, thread status: thread id: 6133493760, thread status: Compaction db/db_test.cc:4680: Failure Expected equality of these values: op_count Which is: 1 expected_count Which is: 0 ``` Reviewed By: hx235 Differential Revision: D52987503 Pulled By: cbi42 fbshipit-source-id: 33b369796f9b97155578b45167e722ddcde93594 |
|
|
Andrew Kryczka
|
5a9ecf6614 |
Automated modernization (#12210)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/12210 Reviewed By: hx235 Differential Revision: D52559771 Pulled By: ajkr fbshipit-source-id: 1ccdd3a0180cc02bc0441f20b0e4a1db50841b03 |
|
|
Changyu Bi
|
d5bc30befa |
Enforce status checking after Valid() returns false for IteratorWrapper (#11975)
Summary: ... when compiled with ASSERT_STATUS_CHECKED = 1. The main change is in iterator_wrapper.h. The remaining changes are just fixing existing unit tests. Adding this check to IteratorWrapper gives a good coverage as the class is used in many places, including child iterators under merging iterator, merging iterator under DB iter, file_iter under level iterator, etc. This change can catch the bug fixed in https://github.com/facebook/rocksdb/issues/11782. Future follow up: enable `ASSERT_STATUS_CHECKED=1` for stress test and for DEBUG_LEVEL=0. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11975 Test Plan: * `ASSERT_STATUS_CHECKED=1 DEBUG_LEVEL=2 make -j32 J=32 check` * I tried to run stress test with `ASSERT_STATUS_CHECKED=1`, but there are a lot of existing stress code that ignore status checking, and fail without the change in this PR. So defer that to a follow up task. Reviewed By: ajkr Differential Revision: D50383790 Pulled By: cbi42 fbshipit-source-id: 1a28ce0f5fdf1890f93400b26b3b1b3a287624ce |
|
|
anand76
|
269478ee46 |
Support compressed and local flash secondary cache stacking (#11812)
Summary: This PR implements support for a three tier cache - primary block cache, compressed secondary cache, and a nvm (local flash) secondary cache. This allows more effective utilization of the nvm cache, and minimizes the number of reads from local flash by caching compressed blocks in the compressed secondary cache. The basic design is as follows - 1. A new secondary cache implementation, ```TieredSecondaryCache```, is introduced. It keeps the compressed and nvm secondary caches and manages the movement of blocks between them and the primary block cache. To setup a three tier cache, we allocate a ```CacheWithSecondaryAdapter```, with a ```TieredSecondaryCache``` instance as the secondary cache. 2. The table reader passes both the uncompressed and compressed block to ```FullTypedCacheInterface::InsertFull```, allowing the block cache to optionally store the compressed block. 3. When there's a miss, the block object is constructed and inserted in the primary cache, and the compressed block is inserted into the nvm cache by calling ```InsertSaved```. This avoids the overhead of recompressing the block, as well as avoiding putting more memory pressure on the compressed secondary cache. 4. When there's a hit in the nvm cache, we attempt to insert the block in the compressed secondary cache and the primary cache, subject to the admission policy of those caches (i.e admit on second access). Blocks/items evicted from any tier are simply discarded. We can easily implement additional admission policies if desired. Todo (In a subsequent PR): 1. Add to db_bench and run benchmarks 2. Add to db_stress Pull Request resolved: https://github.com/facebook/rocksdb/pull/11812 Reviewed By: pdillinger Differential Revision: D49461842 Pulled By: anand1976 fbshipit-source-id: b40ac1330ef7cd8c12efa0a3ca75128e602e3a0b |
|
|
Yu Zhang
|
32fc1e6cdc |
Add unit test for the multiget fix when ReadOptions.read_tier == kPersistedTier and disableWAL == true (#11854)
Summary: Add unit tests for the fix in https://github.com/facebook/rocksdb/pull/11700 Pull Request resolved: https://github.com/facebook/rocksdb/pull/11854 Reviewed By: anand1976 Differential Revision: D49392462 Pulled By: jowlyzhang fbshipit-source-id: bd6978e4888074fa5417f3ccda7a78a2c7eee9c6 |
|
|
Changyu Bi
|
9d71682d1b |
Add statistics `COMPACTION_CPU_TOTAL_TIME` for total compaction time (#11741)
Summary: Existing compaction statistics are `COMPACTION_TIME` and `COMPACTION_CPU_TIME` which are histogram and are logged at the end of a compaction. The new statistics `COMPACTION_CPU_TOTAL_TIME` is for cumulative total compaction time which is updated regularly during a compaction. This allows user to more closely track compaction cpu usage. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11741 Test Plan: * new unit test `DBTestWithParam.CompactionTotalTimeTest` Reviewed By: ajkr Differential Revision: D48608094 Pulled By: cbi42 fbshipit-source-id: b597109f3e4bf2237fb5a216b6fd036e5363b4c0 |
|
|
Changyu Bi
|
76ed9a3990 |
Add missing status check when compiling with `ASSERT_STATUS_CHECKED=1` (#11686)
Summary:
It seems the flag `-fno-elide-constructors` is incorrectly overwritten in Makefile by
|
|
|
Peter Dillinger
|
e214964f40 |
Fix a potential memory leak on row_cache insertion failure (#11682)
Summary: Although the built-in Cache implementations never return failure on Insert without keeping a reference (Handle), a custom implementation could. The code for inserting into row_cache does not keep a reference but does not clean up appropriately on non-OK. This is a fix. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11682 Test Plan: unit test added that previously fails under ASAN Reviewed By: ajkr Differential Revision: D48153831 Pulled By: pdillinger fbshipit-source-id: 86eb7387915c5b38b6ff5dd8deb4e1e223b7d020 |
|
|
Andrew Kryczka
|
05c3b8ecac |
Prepare for specialized interface for row cache (#11620)
Summary: An internal user wants to implement a key-aware row cache policy. For that, they need to know the components of the cache key, especially the user key component. With a specialized `RowCache` interface, we will be able to tell them the components so they won't have to make assumptions about our internal key schema. This PR prepares for the specialized `RowCache` interface by updating the migration plan of https://github.com/facebook/rocksdb/issues/11450. I added a release note for the removed APIs and didn't mention the added ones for now. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11620 Reviewed By: pdillinger Differential Revision: D47536962 Pulled By: ajkr fbshipit-source-id: bbee0fc4ad67fc699a66b8f2b4ea4544dd003691 |
|
|
Changyu Bi
|
bc04ec85db |
Make option `level_compaction_dynamic_level_bytes` true by default (#11525)
Summary: after https://github.com/facebook/rocksdb/issues/11321 and https://github.com/facebook/rocksdb/issues/11340 (both included in RocksDB v8.2), migration from `level_compaction_dynamic_level_bytes=false` to `level_compaction_dynamic_level_bytes=true` is automatic by RocksDB and requires no manual compaction from user. Making the option true by default as it has several advantages: 1. better space amplification guarantee (a more stable LSM shape). 2. compaction is more adaptive to write traffic. 3. automatic draining of unneeded levels. Wiki is updated with more detail: https://github.com/facebook/rocksdb/wiki/Leveled-Compaction#option-level_compaction_dynamic_level_bytes-and-levels-target-size. The PR mostly contains fixes for unit tests as they assumed `level_compaction_dynamic_level_bytes=false`. Most notable change is commit |
|
|
mayue.fight
|
fa878a0107 |
Support to create a CF by importing multiple non-overlapping CFs (#11378)
Summary: The original Feature Request is from [https://github.com/facebook/rocksdb/issues/11317](https://github.com/facebook/rocksdb/issues/11317). Flink uses rocksdb as the state backend, all DB options are the same, and the keys of each DB instance are adjacent and there is no key overlap between two db instances. In the Flink rescaling scenario, it is necessary to quickly split the DB according to a certain key range or quickly merge multiple DBs into one. This PR is mainly used to quickly merge multiple DBs into one. We hope to extend the function of `CreateColumnFamilyWithImports` to support creating ColumnFamily by importing multiple ColumnFamily with no overlapping keys. The import logic is almost the same as `CreateColumnFamilyWithImport`, but it will check whether there is key overlap between CF when importing. The import will fail if there are key overlaps. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11378 Reviewed By: ajkr Differential Revision: D46413709 Pulled By: cbi42 fbshipit-source-id: 846d0049fad11c59cf460fa846c345b26c658dfb |
|
|
Jay Huh
|
81aeb15988 |
Add WaitForCompact with WaitForCompactOptions to public API (#11436)
Summary: Context: This is the first PR for WaitForCompact() Implementation with WaitForCompactOptions. In this PR, we are introducing `Status WaitForCompact(const WaitForCompactOptions& wait_for_compact_options)` in the public API. This currently utilizes the existing internal `WaitForCompact()` implementation (with default abort_on_pause = false). `abort_on_pause` has been moved to `WaitForCompactOptions&`. In the later PRs, we will introduce the following two options in `WaitForCompactOptions` 1. `bool flush = false` by default - If true, flush before waiting for compactions to finish. Must be set to true to ensure no immediate compactions (except perhaps periodic compactions) after closing and re-opening the DB. 2. `bool close_db = false` by default - If true, will also close the DB upon compactions finishing. 1. struct `WaitForCompactOptions` added to options.h and `abort_on_pause` in the internal API moved to the option struct. 2. `Status WaitForCompact(const WaitForCompactOptions& wait_for_compact_options)` introduced in `db.h` 3. Changed the internal WaitForCompact() to `WaitForCompact(const WaitForCompactOptions& wait_for_compact_options)` and checks for the `abort_on_pause` inside the option. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11436 Test Plan: Following tests added - `DBCompactionTest::WaitForCompactWaitsOnCompactionToFinish` - `DBCompactionTest::WaitForCompactAbortOnPauseAborted` - `DBCompactionTest::WaitForCompactContinueAfterPauseNotAborted` - `DBCompactionTest::WaitForCompactShutdownWhileWaiting` - `TransactionTest::WaitForCompactAbortOnPause` NOTE: `TransactionTest::WaitForCompactAbortOnPause` was added to use `StackableDB` to ensure the wrapper function is in place. Reviewed By: pdillinger Differential Revision: D45799659 Pulled By: jaykorean fbshipit-source-id: b5b58f95957f2ab47d1221dee32a61d6cdc4685b |
|
|
Peter Dillinger
|
4067acabca |
Compatibility step for separating BlockCache and GeneralCache APIs (#11450)
Summary: Add two type aliases for Cache: BlockCache and GeneralCache, and add LRUCacheOptions::MakeSharedGeneralCache(). This will ease upgrade to an intended future change to separate the cache API between block cache and other (general) uses, including row cache. Separating the APIs will make it easier to expose more details of block caching for customization. For example, it would be nice to pass the file unique ID and offset as the logical cache key instead of using a Slice, which could facilitate some file-specific customizations in block cache. This would also make it clear that HyperClockCache is not usable as a general cache, because it can only deal with fixed-size block cache keys. block_cache, row_cache, and blob_cache are the uses of Cache in the public API. blob_cache should be able to use BlockCache while row_cache is a GeneralCache user, as its keys are of arbitrary size. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11450 Test Plan: see updated unit test. Reviewed By: anand1976 Differential Revision: D45882067 Pulled By: pdillinger fbshipit-source-id: ff5d9f0b644f87ae337a29a7728ce3ed07b2a4b2 |
|
|
mayue.fight
|
8d8eb0e77e |
Support Clip DB to KeyRange (#11379)
Summary: This PR is part of the request https://github.com/facebook/rocksdb/issues/11317. (Another part is https://github.com/facebook/rocksdb/pull/11378) ClipDB() will clip the entries in the CF according to the range [begin_key, end_key). All the entries outside this range will be completely deleted (including tombstones). This feature is mainly used to ensure that there is no overlapping Key when calling CreateColumnFamilyWithImports() to import multiple CFs. When Calling ClipDB [begin, end), there are the following steps 1. Quickly and directly delete files without overlap DeleteFilesInRanges(nullptr, begin) + DeleteFilesInRanges(end, nullptr) 2. Delete the Key outside the range Delete[smallest_key, begin) + Delete[end, largest_key] 3. Delete the tombstone through Manul Compact CompactRange(option, nullptr, nullptr) Pull Request resolved: https://github.com/facebook/rocksdb/pull/11379 Reviewed By: ajkr Differential Revision: D45840358 Pulled By: cbi42 fbshipit-source-id: 54152e8a45fd8ede137f99787eb252f0b51440a4 |
|
|
Jay Huh
|
586d78b31e |
Remove wait_unscheduled from waitForCompact internal API (#11443)
Summary: Context: In pull request https://github.com/facebook/rocksdb/issues/11436, we are introducing a new public API `waitForCompact(const WaitForCompactOptions& wait_for_compact_options)`. This API invokes the internal implementation `waitForCompact(bool wait_unscheduled=false)`. The unscheduled parameter indicates the compactions that are not yet scheduled but are required to process items in the queue. In certain cases, we are unable to wait for compactions, such as during a shutdown or when background jobs are paused. It is important to return the appropriate status in these scenarios. For all other cases, we should wait for all compaction and flush jobs, including the unscheduled ones. The primary purpose of this new API is to wait until the system has resolved its compaction debt. Currently, the usage of `wait_unscheduled` is limited to test code. This pull request eliminates the usage of wait_unscheduled. The internal `waitForCompact()` API now waits for unscheduled compactions unless the db is undergoing a shutdown. In the event of a shutdown, the API returns `Status::ShutdownInProgress()`. Additionally, a new parameter, `abort_on_pause`, has been introduced with a default value of `false`. This parameter addresses the possibility of waiting indefinitely for unscheduled jobs if `PauseBackgroundWork()` was called before `waitForCompact()` is invoked. By setting `abort_on_pause` to `true`, the API will immediately return `Status::Aborted`. Furthermore, all tests that previously called `waitForCompact(true)` have been fixed. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11443 Test Plan: Existing tests that involve a shutdown in progress: - DBCompactionTest::CompactRangeShutdownWhileDelayed - DBTestWithParam::PreShutdownMultipleCompaction - DBTestWithParam::PreShutdownCompactionMiddle Reviewed By: pdillinger Differential Revision: D45923426 Pulled By: jaykorean fbshipit-source-id: 7dc93fe6a6841a7d9d2d72866fa647090dba8eae |
|
|
Peter Dillinger
|
206fdea3d9 |
Change internal headers with duplicate names (#11408)
Summary: In IDE navigation I find it annoying that there are two statistics.h files (etc.) and often land on the wrong one. Here I migrate several headers to use the blah.h <- blah_impl.h <- blah.cc idiom. Although clang-format wants "blah.h" to be the top include for "blah.cc", I think overall this is an improvement. No public API changes. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11408 Test Plan: existing tests Reviewed By: ltamasi Differential Revision: D45456696 Pulled By: pdillinger fbshipit-source-id: 809d931253f3272c908cf5facf7e1d32fc507373 |
|
|
clundro
|
50b33ebb1b |
remove redundant move (#11418)
Summary:
when I use g++-13 to exec the `make all` command, the output throws the warnings.
```
db/compaction/compaction_job_test.cc: In member function ‘void rocksdb::CompactionJobTestBase::AddMockFile(const rocksdb::mock::KVVector&, int)’:
db/compaction/compaction_job_test.cc:376:57: error: redundant move in initialization [-Werror=redundant-move]
376 | env_, GenerateFileName(file_number), std::move(contents)));
| ~~~~~~~~~^~~~~~~~~~
db/compaction/compaction_job_test.cc:375:7: note: in expansion of macro ‘EXPECT_OK’
375 | EXPECT_OK(mock_table_factory_->CreateMockTable(
| ^~~~~~~~~
db/compaction/compaction_job_test.cc:376:57: note: remove ‘std::move’ call
376 | env_, GenerateFileName(file_number), std::move(contents)));
| ~~~~~~~~~^~~~~~~~~~
db/compaction/compaction_job_test.cc:375:7: note: in expansion of macro ‘EXPECT_OK’
375 | EXPECT_OK(mock_table_factory_->CreateMockTable(
| ^~~~~~~~~
cc1plus: all warnings being treated as errors
make: *** [Makefile:2507: db/compaction/compaction_job_test.o] Error 1
```
and I also add some `(void)unused_variable` statements because of the cmake argument `-Wunused-but-set-variable -Wunused-but-set-variable`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11418
Reviewed By: akankshamahajan15
Differential Revision: D45528223
Pulled By: ajkr
fbshipit-source-id: fee1a77c30039a56b481de953f0a834cc788abbc
|
|
|
Changyu Bi
|
b3c43a5b99 |
Drain unnecessary levels when `level_compaction_dynamic_level_bytes=true` (#11340)
Summary: When a user migrates to level compaction + `level_compaction_dynamic_level_bytes=true`, or when a DB shrinks, there can be unnecessary levels in the DB. Before this PR, this is no way to remove these levels except a manual compaction. These extra unnecessary levels make it harder to guarantee max_bytes_for_level_multiplier and can cause extra space amp. This PR boosts compaction score for these levels to allow RocksDB to automatically drain these levels. Together with https://github.com/facebook/rocksdb/issues/11321, this makes migration to `level_compaction_dynamic_level_bytes=true` automatic without needing user to do a one time full manual compaction. Credit: this PR is modified from https://github.com/facebook/rocksdb/issues/3921. Pull Request resolved: https://github.com/facebook/rocksdb/pull/11340 Test Plan: - New unit tests - `python3 tools/db_crashtest.py whitebox --simple` which randomly sets level_compaction_dynamic_level_bytes in each run. Reviewed By: ajkr Differential Revision: D44563884 Pulled By: cbi42 fbshipit-source-id: e20d3620bd73dff22be18c5a91a07f340740bcc8 |
|
|
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 |
|
|
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
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Andrew Kryczka
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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 |
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Yanqin Jin
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7d26e4c5a3 |
Basic Support for Merge with user-defined timestamp (#10819)
Summary:
This PR implements the originally disabled `Merge()` APIs when user-defined timestamp is enabled.
Simplest usage:
```cpp
// assume string append merge op is used with '.' as delimiter.
// ts1 < ts2
db->Put(WriteOptions(), "key", ts1, "v0");
db->Merge(WriteOptions(), "key", ts2, "1");
ReadOptions ro;
ro.timestamp = &ts2;
db->Get(ro, "key", &value);
ASSERT_EQ("v0.1", value);
```
Some code comments are added for clarity.
Note: support for timestamp in `DB::GetMergeOperands()` will be done in a follow-up PR.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10819
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D40603195
Pulled By: riversand963
fbshipit-source-id: f96d6f183258f3392d80377025529f7660503013
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Yueh-Hsuan Chiang
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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 |
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Changyu Bi
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a6ce1955b1 |
Fix flaky test ShuttingDownNotBlockStalledWrites (#10800)
Summary: DBTest::ShuttingDownNotBlockStalledWrites is flaky, added new sync point dependency to fix it. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10800 Test Plan: gtest-parallel --repeat=1000 ./db_test --gtest_filter="*ShuttingDownNotBlockStalledWrites" Reviewed By: jay-zhuang Differential Revision: D40239116 Pulled By: jay-zhuang fbshipit-source-id: 8c2d7e7df58f202d287bd9f5c9b60b7eff270d0c |
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Qingping Wang
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a45e6878f3 |
fix issue 10751 (#10765)
Summary: Fix https://github.com/facebook/rocksdb/issues/10751 where a stalled write could be blocked forever when DB shutdown. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10765 Reviewed By: ajkr Differential Revision: D40110069 Pulled By: ajkr fbshipit-source-id: 598c05777db9be85913a0a85e421b3295ecdff5e |
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Jay Zhuang
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edae671ce0 |
Re-enable SuggestCompactRangeTest and add Universal Compaction test (#10473)
Summary: The feature `SuggestCompactRange()` is still experimental. Just re-add the test back. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10473 Test Plan: CI Reviewed By: akankshamahajan15 Differential Revision: D38427153 Pulled By: jay-zhuang fbshipit-source-id: 0b4491c947cbce6c18ff147b167e3c678633129a |
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Jay Zhuang
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fcccc412d7 |
Remove Travis CI (#10407)
Summary: Travis CI is depreciated and haven't been maintained for some time. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10407 Reviewed By: ajkr Differential Revision: D38078382 Pulled By: jay-zhuang fbshipit-source-id: f42057f2f41f722bdce56bf195f67a94835191fb |
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Yu Zhao 00540916
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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 |
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Andrew Kryczka
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25cc564ff7 |
Make RateLimiter not Customizable (#10378)
Summary: (PR created for informational/testing purposes only.) - Fixes lost dynamic updates to GenericRateLimiter bandwidth using `SetBytesPerSecond()` - Benefit over #10374 is eliminating race conditions with Configurable framework. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10378 Reviewed By: pdillinger Differential Revision: D37914865 fbshipit-source-id: d4f566d60ec9726d26932388c61671adf0ee0f30 |
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Levi Tamasi
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c73d2a9d18 |
Add API for writing wide-column entities (#10242)
Summary: The patch builds on https://github.com/facebook/rocksdb/pull/9915 and adds a new API called `PutEntity` that can be used to write a wide-column entity to the database. The new API is added to both `DB` and `WriteBatch`. Note that currently there is no way to retrieve these entities; more precisely, all read APIs (`Get`, `MultiGet`, and iterator) return `NotSupported` when they encounter a wide-column entity that is required to answer a query. Read-side support (as well as other missing functionality like `Merge`, compaction filter, and timestamp support) will be added in later PRs. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10242 Test Plan: `make check` Reviewed By: riversand963 Differential Revision: D37369748 Pulled By: ltamasi fbshipit-source-id: 7f5e412359ed7a400fd80b897dae5599dbcd685d |
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Andrew Kryczka
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5d6005c780 |
Add WriteOptions::protection_bytes_per_key (#10037)
Summary: Added an option, `WriteOptions::protection_bytes_per_key`, that controls how many bytes per key we use for integrity protection in `WriteBatch`. It takes effect when `WriteBatch::GetProtectionBytesPerKey() == 0`. Currently the only supported value is eight. Invoking a user API with it set to any other nonzero value will result in `Status::NotSupported` returned to the user. There is also a bug fix for integrity protection with `inplace_callback`, where we forgot to take into account the possible change in varint length when calculating KV checksum for the final encoded buffer. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10037 Test Plan: - Manual - Set default value of `WriteOptions::protection_bytes_per_key` to eight and ran `make check -j24` - Enabled in MyShadow for 1+ week - Automated - Unit tests have a `WriteMode` that enables the integrity protection via `WriteOptions` - Crash test - in most cases, use `WriteOptions::protection_bytes_per_key` to enable integrity protection Reviewed By: cbi42 Differential Revision: D36614569 Pulled By: ajkr fbshipit-source-id: 8650087ceac9b61b560f1e5fafe5e1baf9c725fb |
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mpoeter
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77f4799515 |
Fix potential leak when reusing PinnableSlice instances. (#10166)
Summary:
`PinnableSlice` may hold a handle to a cache value which must be released to correctly decrement the ref-counter. However, when `PinnableSlice` variables are reused, e.g. like this:
```
PinnableSlice pin_slice;
db.Get("foo", &pin_slice);
db.Get("foo", &pin_slice);
```
then the second `Get` simply overwrites the old value in `pin_slice` and the handle returned by the first `Get` is _not_ released.
This PR adds `Reset` calls to the `Get`/`MultiGet` calls that accept `PinnableSlice` arguments to ensure proper cleanup of old values.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10166
Reviewed By: hx235
Differential Revision: D37151632
Pulled By: ajkr
fbshipit-source-id: 9dd3c3288300f560531b843f67db11aeb569a9ff
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Yanqin Jin
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1777e5f7e9 |
Snapshots with user-specified timestamps (#9879)
Summary: In RocksDB, keys are associated with (internal) sequence numbers which denote when the keys are written to the database. Sequence numbers in different RocksDB instances are unrelated, thus not comparable. It is nice if we can associate sequence numbers with their corresponding actual timestamps. One thing we can do is to support user-defined timestamp, which allows the applications to specify the format of custom timestamps and encode a timestamp with each key. More details can be found at https://github.com/facebook/rocksdb/wiki/User-defined-Timestamp-%28Experimental%29. This PR provides a different but complementary approach. We can associate rocksdb snapshots (defined in https://github.com/facebook/rocksdb/blob/7.2.fb/include/rocksdb/snapshot.h#L20) with **user-specified** timestamps. Since a snapshot is essentially an object representing a sequence number, this PR establishes a bi-directional mapping between sequence numbers and timestamps. In the past, snapshots are usually taken by readers. The current super-version is grabbed, and a `rocksdb::Snapshot` object is created with the last published sequence number of the super-version. You can see that the reader actually has no good idea of what timestamp to assign to this snapshot, because by the time the `GetSnapshot()` is called, an arbitrarily long period of time may have already elapsed since the last write, which is when the last published sequence number is written. This observation motivates the creation of "timestamped" snapshots on the write path. Currently, this functionality is exposed only to the layer of `TransactionDB`. Application can tell RocksDB to create a snapshot when a transaction commits, effectively associating the last sequence number with a timestamp. It is also assumed that application will ensure any two snapshots with timestamps should satisfy the following: ``` snapshot1.seq < snapshot2.seq iff. snapshot1.ts < snapshot2.ts ``` If the application can guarantee that when a reader takes a timestamped snapshot, there is no active writes going on in the database, then we also allow the user to use a new API `TransactionDB::CreateTimestampedSnapshot()` to create a snapshot with associated timestamp. Code example ```cpp // Create a timestamped snapshot when committing transaction. txn->SetCommitTimestamp(100); txn->SetSnapshotOnNextOperation(); txn->Commit(); // A wrapper API for convenience Status Transaction::CommitAndTryCreateSnapshot( std::shared_ptr<TransactionNotifier> notifier, TxnTimestamp ts, std::shared_ptr<const Snapshot>* ret); // Create a timestamped snapshot if caller guarantees no concurrent writes std::pair<Status, std::shared_ptr<const Snapshot>> snapshot = txn_db->CreateTimestampedSnapshot(100); ``` The snapshots created in this way will be managed by RocksDB with ref-counting and potentially shared with other readers. We provide the following APIs for readers to retrieve a snapshot given a timestamp. ```cpp // Return the timestamped snapshot correponding to given timestamp. If ts is // kMaxTxnTimestamp, then we return the latest timestamped snapshot if present. // Othersise, we return the snapshot whose timestamp is equal to `ts`. If no // such snapshot exists, then we return null. std::shared_ptr<const Snapshot> TransactionDB::GetTimestampedSnapshot(TxnTimestamp ts) const; // Return the latest timestamped snapshot if present. std::shared_ptr<const Snapshot> TransactionDB::GetLatestTimestampedSnapshot() const; ``` We also provide two additional APIs for stats collection and reporting purposes. ```cpp Status TransactionDB::GetAllTimestampedSnapshots( std::vector<std::shared_ptr<const Snapshot>>& snapshots) const; // Return timestamped snapshots whose timestamps fall in [ts_lb, ts_ub) and store them in `snapshots`. Status TransactionDB::GetTimestampedSnapshots( TxnTimestamp ts_lb, TxnTimestamp ts_ub, std::vector<std::shared_ptr<const Snapshot>>& snapshots) const; ``` To prevent the number of timestamped snapshots from growing infinitely, we provide the following API to release timestamped snapshots whose timestamps are older than or equal to a given threshold. ```cpp void TransactionDB::ReleaseTimestampedSnapshotsOlderThan(TxnTimestamp ts); ``` Before shutdown, RocksDB will release all timestamped snapshots. Comparison with user-defined timestamp and how they can be combined: User-defined timestamp persists every key with a timestamp, while timestamped snapshots maintain a volatile mapping between snapshots (sequence numbers) and timestamps. Different internal keys with the same user key but different timestamps will be treated as different by compaction, thus a newer version will not hide older versions (with smaller timestamps) unless they are eligible for garbage collection. In contrast, taking a timestamped snapshot at a certain sequence number and timestamp prevents all the keys visible in this snapshot from been dropped by compaction. Here, visible means (seq < snapshot and most recent). The timestamped snapshot supports the semantics of reading at an exact point in time. Timestamped snapshots can also be used with user-defined timestamp. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9879 Test Plan: ``` make check TEST_TMPDIR=/dev/shm make crash_test_with_txn ``` Reviewed By: siying Differential Revision: D35783919 Pulled By: riversand963 fbshipit-source-id: 586ad905e169189e19d3bfc0cb0177a7239d1bd4 |
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Peter Dillinger
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d3a3b02134 |
Fix bug with kHashSearch and changing prefix_extractor with SetOptions (#10128)
Summary: When opening an SST file created using index_type=kHashSearch, the *current* prefix_extractor would be saved, and used with hash index if the *new current* prefix_extractor at query time is compatible with the SST file. This is a problem if the prefix_extractor at SST open time is not compatible but SetOptions later changes (back) to one that is compatible. This change fixes that by using the known compatible (or missing) prefix extractor we save for use with prefix filtering. Detail: I have moved the InternalKeySliceTransform wrapper to avoid some indirection and remove unnecessary fields. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10128 Test Plan: expanded unit test (using some logic from https://github.com/facebook/rocksdb/issues/10122) that fails before fix and probably covers some other previously uncovered cases. Reviewed By: siying Differential Revision: D36955738 Pulled By: pdillinger fbshipit-source-id: 0c78a6b0d24054ef2f3cb237bf010c1c5589fb10 |
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Akanksha Mahajan
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700d597bd8 |
Expose unix time in rocksdb::Snapshot (#9923)
Summary: RocksDB snapshot already has a member unix_time_ set after snapshot is taken. It is now exposed through GetSnapshotTime() API. Pull Request resolved: https://github.com/facebook/rocksdb/pull/9923 Test Plan: Update unit tests Reviewed By: riversand963 Differential Revision: D36048275 Pulled By: akankshamahajan15 fbshipit-source-id: 825210ec287deb0bc3aaa9b8e1f079f07ad686fa |