Commit Graph

74 Commits

Author SHA1 Message Date
Peter Dillinger 13ef21c22e default_write_temperature option (#12388)
Summary:
Currently SST files that aren't applicable to last_level_temperature nor file_temperature_age_thresholds are written with temperature kUnknown, which is a little weird and doesn't support CF-based tiering. The default_temperature option only affects how kUnknown is interpreted for stats.

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

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

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

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

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

Reviewed By: jowlyzhang

Differential Revision: D54266574

Pulled By: pdillinger

fbshipit-source-id: c9ec9a74dbf22be6e986f77f9689d05fea8ef0bb
2024-02-28 14:36:13 -08:00
Peter Dillinger d780e7a561 Remove `bottommost_temperature` (#12389)
Summary:
deprecated option already replaced by `last_level_temperature`. (Keeping recognition of the option in old options files.)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12389

Test Plan: tests updated

Reviewed By: jowlyzhang, cbi42

Differential Revision: D54267946

Pulled By: pdillinger

fbshipit-source-id: 65c49b15e7394829c1f3b44edd4179d2daff6017
2024-02-27 14:48:00 -08:00
Andrew Kryczka 8e29f243c9 No filesystem reads during `Merge()` writes (#12365)
Summary:
This occasional filesystem read in the write path has caused user pain. It doesn't seem very useful considering it only limits one component's merge chain length, and only helps merge uncached (i.e., infrequently read) values. This PR proposes allowing `max_successive_merges` to be exceeded when the value cannot be read from in-memory components. I included a rollback flag (`strict_max_successive_merges`) just in case.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12365

Test Plan:
"rocksdb.block.cache.data.add" is number of data blocks read from filesystem. Since the benchmark is write-only, compaction is disabled, and flush doesn't read data blocks, any nonzero value means the user write issued the read.

```
$ for s in false true; do echo -n "strict_max_successive_merges=$s: " && ./db_bench -value_size=64 -write_buffer_size=131072 -writes=128 -num=1 -benchmarks=mergerandom,flush,mergerandom -merge_operator=stringappend -disable_auto_compactions=true -compression_type=none -strict_max_successive_merges=$s -max_successive_merges=100 -statistics=true |& grep 'block.cache.data.add COUNT' ; done
strict_max_successive_merges=false: rocksdb.block.cache.data.add COUNT : 0
strict_max_successive_merges=true: rocksdb.block.cache.data.add COUNT : 1
```

Reviewed By: hx235

Differential Revision: D53982520

Pulled By: ajkr

fbshipit-source-id: e40f761a60bd601f232417ac0058e4a33ee9c0f4
2024-02-21 13:15:27 -08:00
Changyu Bi 5620efc794 Remove deprecated option `ignore_max_compaction_bytes_for_input` (#12323)
Summary:
The option is introduced in https://github.com/facebook/rocksdb/issues/10835 to allow disabling the new compaction behavior if it's not safe. The option is enabled by default and there has not been a need to disable it. So it should be safe to remove now.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12323

Reviewed By: ajkr

Differential Revision: D53330336

Pulled By: cbi42

fbshipit-source-id: 36eef4664ac96b3a7ed627c48bd6610b0a7eafc5
2024-02-02 17:09:42 -08:00
Changyu Bi ace1721b28 Remove deprecated option `level_compaction_dynamic_file_size` (#12325)
Summary:
The option is introduced in https://github.com/facebook/rocksdb/issues/10655 to allow reverting to old behavior. The option is enabled by default and there has not been a need to disable it. Remove it for 9.0 release. Also fixed and improved a few unit tests that depended on setting this option to false.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12325

Test Plan: existing tests.

Reviewed By: hx235

Differential Revision: D53369430

Pulled By: cbi42

fbshipit-source-id: 0ec2440ca8d88db7f7211c581542c7581bd4d3de
2024-02-02 15:37:40 -08:00
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
2024-01-31 16:30:26 -08:00
Yu Zhang 1e77e35d26 Add a per column family default temperature option for accounting (#11708)
Summary:
Add a column family option `default_temperature` that will be used for file reading accounting purpose, such as io statistics, for files that don't have an explicitly set temperature.

This options is not a mutable one, changing its value would require a DB restart. This is to avoid the confusion that had the option being a mutable one, the users may expect it to take effect on all files immediately, while in reality, it would only become effective for SST files opened in the future.

This `default_temperature` also just affect accounting during one DB session. It won't be recorded in manifest as the file's temperature and can be different across different DB sessions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11708

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

Reviewed By: pdillinger

Differential Revision: D48375763

Pulled By: jowlyzhang

fbshipit-source-id: eb756696c14a694c6e2a93d2bb6f040563194981
2023-08-17 17:06:57 -07:00
Changyu Bi d1ff401472 Delay bottommost level single file compactions (#11701)
Summary:
For leveled compaction, RocksDB has a special kind of compaction with reason "kBottommmostFiles" that compacts bottommost level files to clear data held by snapshots (more detail in https://github.com/facebook/rocksdb/issues/3009). Such compactions can happen soon after a relevant snapshot is released. For some use cases, a bottommost file may contain only a small amount of keys that can be cleared, so compacting such a file has a high write amp. In addition, these bottommost files may be compacted in compactions with reason other than "kBottommmostFiles" if we wait for some time (so that enough data is ingested to trigger such a compaction). This PR introduces an option `bottommost_file_compaction_delay` to specify the delay of these bottommost level single file compactions.

* The main change is in `VersionStorageInfo::ComputeBottommostFilesMarkedForCompaction()` where we only add a file to `bottommost_files_marked_for_compaction_` if it oldest_snapshot is larger than its non-zero largest_seqno **and** the file is old enough. Note that if a file is not old enough but its largest_seqno is less than oldest_snapshot, we exclude it from the calculation of `bottommost_files_mark_threshold_`. This makes the change simpler, but such a file's eligibility for compaction will only be checked the next time `ComputeBottommostFilesMarkedForCompaction()` is called. This happens when a new Version is created (compaction, flush, SetOptions()...), a new enough snapshot is released (`VersionStorageInfo::UpdateOldestSnapshot()`) or when a compaction is picked and compaction score has to be re-calculated.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11701

Test Plan:
* Add two unit tests to test when bottommost_file_compaction_delay > 0.
* Ran crash test with the new option.

Reviewed By: jaykorean, ajkr

Differential Revision: D48331564

Pulled By: cbi42

fbshipit-source-id: c584f3dc5f6354fce3ed65f4c6366dc450b15ba8
2023-08-16 17:45:44 -07:00
Vardhan 87a21d08fe Add an option to trigger flush when the number of range deletions reach a threshold (#11358)
Summary:
Add a mutable column family option `memtable_max_range_deletions`. When non-zero, RocksDB will try to flush the current memtable after it has at least `memtable_max_range_deletions` range deletions. Java API is added and crash test is updated accordingly to randomly enable this option.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11358

Test Plan:
* New unit test: `DBRangeDelTest.MemtableMaxRangeDeletions`
* Ran crash test `python3 ./tools/db_crashtest.py whitebox --simple --memtable_max_range_deletions=20` and saw logs showing flushed memtables usually with 20 range deletions.

Reviewed By: ajkr

Differential Revision: D46582680

Pulled By: cbi42

fbshipit-source-id: f23d6fa8d8264ecf0a18d55c113ba03f5e2504da
2023-08-02 19:58:56 -07:00
Changyu Bi 62fc15f009 Block per key-value checksum (#11287)
Summary:
add option `block_protection_bytes_per_key` and implementation for block per key-value checksum. The main changes are
1. checksum construction and verification in block.cc/h
2. pass the option `block_protection_bytes_per_key` around (mainly for methods defined in table_cache.h)
3. unit tests/crash test updates

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

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

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

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

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

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

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

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

Reviewed By: ajkr

Differential Revision: D43970708

Pulled By: cbi42

fbshipit-source-id: ef98d898b71779846fa74212b9ec9e08b7183940
2023-04-25 12:08:23 -07:00
Yu Zhang 647cd73674 Initial add UDT in memtable only option (#11362)
Summary:
This option is immutable through the life time of the DB open. For now, updating its value between different DB open sessions is also a non compatible change. When I work on support for updating comparator, the type of updates accepted for this option will be supported then.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11362

Test Plan: `make check`

Reviewed By: ltamasi

Differential Revision: D44873870

Pulled By: jowlyzhang

fbshipit-source-id: aa02094754b58d99abf9af4c9a8108c1350254cb
2023-04-11 17:50:34 -07:00
sdong 4720ba4391 Remove RocksDB LITE (#11147)
Summary:
We haven't been actively mantaining RocksDB LITE recently and the size must have been gone up significantly. We are removing the support.

Most of changes were done through following comments:

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

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

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

Test Plan: See CI

Reviewed By: pdillinger

Differential Revision: D42796341

fbshipit-source-id: 4920e15fc2060c2cd2221330a6d0e5e65d4b7fe2
2023-01-27 13:14:19 -08:00
Changyu Bi 333abe9c55 Ignore max_compaction_bytes for compaction input that are within output key-range (#10835)
Summary:
When picking compaction input files, we sometimes stop picking a file that is fully included in the output key-range due to hitting max_compaction_bytes. Including these input files can potentially reduce WA at the expense of larger compactions. Larger compaction should be fine as files from input level are usually 10X smaller than files from output level. This PR adds a mutable CF option `ignore_max_compaction_bytes_for_input` that is enabled by default. We can remove this option once we are sure it is safe.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10835

Test Plan:
- CI, a unit test on max_compaction_bytes fails before turning this flag off.
- Benchmark does not show much difference in WA: `./db_bench --benchmarks=fillrandom,waitforcompaction,stats,levelstats -max_background_jobs=12 -num=2000000000 -target_file_size_base=33554432 --write_buffer_size=33554432`
```
main:
** 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      3/0   91.59 MB   0.8     70.9     0.0     70.9     200.8    129.9       0.0   1.5     25.2     71.2   2886.55           2463.45      9725    0.297   1093M   254K       0.0       0.0
  L1      9/0   248.03 MB   1.0    392.0   129.8    262.2     391.7    129.5       0.0   3.0     69.0     68.9   5821.71           5536.90       804    7.241   6029M  5814K       0.0       0.0
  L2     87/0    2.50 GB   1.0    537.0   128.5    408.5     533.8    125.2       0.7   4.2     69.5     69.1   7912.24           7323.70      4417    1.791   8299M    36M       0.0       0.0
  L3    836/0   24.99 GB   1.0    616.9   118.3    498.7     594.5     95.8       5.2   5.0     66.9     64.5   9442.38           8490.28      4204    2.246   9749M   306M       0.0       0.0
  L4   2355/0   62.95 GB   0.3     67.3    37.1     30.2      54.2     24.0      38.9   1.5     72.2     58.2    954.37            821.18       917    1.041   1076M   173M       0.0       0.0
 Sum   3290/0   90.77 GB   0.0   1684.2   413.7   1270.5    1775.0    504.5      44.9  13.7     63.8     67.3  27017.25          24635.52     20067    1.346     26G   522M       0.0       0.0

Cumulative compaction: 1774.96 GB write, 154.29 MB/s write, 1684.19 GB read, 146.40 MB/s read, 27017.3 seconds

This PR:
** 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      3/0   45.71 MB   0.8     72.9     0.0     72.9     202.8    129.9       0.0   1.6     25.4     70.7   2938.16           2510.36      9741    0.302   1124M   265K       0.0       0.0
  L1      8/0   234.54 MB   0.9    384.5   129.8    254.7     384.2    129.6       0.0   3.0     69.0     68.9   5708.08           5424.43       791    7.216   5913M  5753K       0.0       0.0
  L2     84/0    2.47 GB   1.0    543.1   128.6    414.5     539.9    125.4       0.7   4.2     69.6     69.2   7989.31           7403.13      4418    1.808   8393M    36M       0.0       0.0
  L3    839/0   24.96 GB   1.0    615.6   118.4    497.2     593.2     96.0       5.1   5.0     66.6     64.1   9471.23           8489.31      4193    2.259   9726M   306M       0.0       0.0
  L4   2360/0   63.04 GB   0.3     67.6    37.3     30.3      54.4     24.1      38.9   1.5     71.5     57.6    967.30            827.99       907    1.066   1080M   173M       0.0       0.0
 Sum   3294/0   90.75 GB   0.0   1683.8   414.2   1269.6    1774.5    504.9      44.8  13.7     63.7     67.1  27074.08          24655.22     20050    1.350     26G   522M       0.0       0.0

Cumulative compaction: 1774.52 GB write, 157.09 MB/s write, 1683.77 GB read, 149.06 MB/s read, 27074.1 seconds
```

Reviewed By: ajkr

Differential Revision: D40518319

Pulled By: cbi42

fbshipit-source-id: f4ea614bc0ebefe007ffaf05bb9aec9a8ca25b60
2022-10-21 10:22:41 -07:00
Jay Zhuang c401f285c3 Add option `preserve_internal_time_seconds` to preserve the time info (#10747)
Summary:
Add option `preserve_internal_time_seconds` to preserve the internal
time information.
It's mostly for the migration of the existing data to tiered storage (
`preclude_last_level_data_seconds`). When the tiering feature is just
enabled, the existing data won't have the time information to decide if
it's hot or cold. Enabling this feature will start collect and preserve
the time information for the new data.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10747

Reviewed By: siying

Differential Revision: D39910141

Pulled By: siying

fbshipit-source-id: 25c21638e37b1a7c44006f636b7d714fe7242138
2022-10-07 18:49:40 -07:00
Jay Zhuang f3cc66632b Align compaction output file boundaries to the next level ones (#10655)
Summary:
Try to align the compaction output file boundaries to the next level ones
(grandparent level), to reduce the level compaction write-amplification.

In level compaction, there are "wasted" data at the beginning and end of the
output level files. Align the file boundary can avoid such "wasted" compaction.
With this PR, it tries to align the non-bottommost level file boundaries to its
next level ones. It may cut file when the file size is large enough (at least
50% of target_file_size) and not too large (2x target_file_size).

db_bench shows about 12.56% compaction reduction:
```
TEST_TMPDIR=/data/dbbench2 ./db_bench --benchmarks=fillrandom,readrandom -max_background_jobs=12 -num=400000000 -target_file_size_base=33554432

# baseline:
Flush(GB): cumulative 25.882, interval 7.216
Cumulative compaction: 285.90 GB write, 162.36 MB/s write, 269.68 GB read, 153.15 MB/s read, 2926.7 seconds

# with this change:
Flush(GB): cumulative 25.882, interval 7.753
Cumulative compaction: 249.97 GB write, 141.96 MB/s write, 233.74 GB read, 132.74 MB/s read, 2534.9 seconds
```

The compaction simulator shows a similar result (14% with 100G random data).
As a side effect, with this PR, the SST file size can exceed the
target_file_size, but is capped at 2x target_file_size. And there will be
smaller files. Here are file size statistics when loading 100GB with the target
file size 32MB:
```
          baseline      this_PR
count  1.656000e+03  1.705000e+03
mean   3.116062e+07  3.028076e+07
std    7.145242e+06  8.046139e+06
```

The feature is enabled by default, to revert to the old behavior disable it
with `AdvancedColumnFamilyOptions.level_compaction_dynamic_file_size = false`

Also includes https://github.com/facebook/rocksdb/issues/1963 to cut file before skippable grandparent file. Which is for
use case like user adding 2 or more non-overlapping data range at the same
time, it can reduce the overlapping of 2 datasets in the lower levels.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10655

Reviewed By: cbi42

Differential Revision: D39552321

Pulled By: jay-zhuang

fbshipit-source-id: 640d15f159ab0cd973f2426cfc3af266fc8bdde2
2022-09-29 19:43:55 -07:00
Changyu Bi fd165c869d Add memtable per key-value checksum (#10281)
Summary:
Append per key-value checksum to internal key. These checksums are verified on read paths including Get, Iterator and during Flush. Get and Iterator will return `Corruption` status if there is a checksum verification failure. Flush will make DB become read-only upon memtable entry checksum verification failure.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10281

Test Plan:
- Added new unit test cases: `make check`
- Benchmark on memtable insert
```
TEST_TMPDIR=/dev/shm/memtable_write ./db_bench -benchmarks=fillseq -disable_wal=true -max_write_buffer_number=100 -num=10000000 -min_write_buffer_number_to_merge=100

# avg over 10 runs
Baseline: 1166936 ops/sec
memtable 2 bytes kv checksum : 1.11674e+06 ops/sec (-4%)
memtable 2 bytes kv checksum + write batch 8 bytes kv checksum: 1.08579e+06 ops/sec (-6.95%)
write batch 8 bytes kv checksum: 1.17979e+06 ops/sec (+1.1%)
```
-  Benchmark on only memtable read: ops/sec dropped 31% for `readseq` due to time spend on verifying checksum.
ops/sec for `readrandom` dropped ~6.8%.
```
# Readseq
sudo TEST_TMPDIR=/dev/shm/memtable_read ./db_bench -benchmarks=fillseq,readseq"[-X20]" -disable_wal=true -max_write_buffer_number=100 -num=10000000 -min_write_buffer_number_to_merge=100

readseq [AVG    20 runs] : 7432840 (± 212005) ops/sec;  822.3 (± 23.5) MB/sec
readseq [MEDIAN 20 runs] : 7573878 ops/sec;  837.9 MB/sec

With -memtable_protection_bytes_per_key=2:

readseq [AVG    20 runs] : 5134607 (± 119596) ops/sec;  568.0 (± 13.2) MB/sec
readseq [MEDIAN 20 runs] : 5232946 ops/sec;  578.9 MB/sec

# Readrandom
sudo TEST_TMPDIR=/dev/shm/memtable_read ./db_bench -benchmarks=fillrandom,readrandom"[-X10]" -disable_wal=true -max_write_buffer_number=100 -num=1000000 -min_write_buffer_number_to_merge=100
readrandom [AVG    10 runs] : 140236 (± 3938) ops/sec;    9.8 (± 0.3) MB/sec
readrandom [MEDIAN 10 runs] : 140545 ops/sec;    9.8 MB/sec

With -memtable_protection_bytes_per_key=2:
readrandom [AVG    10 runs] : 130632 (± 2738) ops/sec;    9.1 (± 0.2) MB/sec
readrandom [MEDIAN 10 runs] : 130341 ops/sec;    9.1 MB/sec
```

- Stress test: `python3 -u tools/db_crashtest.py whitebox --duration=1800`

Reviewed By: ajkr

Differential Revision: D37607896

Pulled By: cbi42

fbshipit-source-id: fdaefb475629d2471780d4a5f5bf81b44ee56113
2022-08-12 13:51:32 -07:00
Jay Zhuang 3f763763aa Change `bottommost_temperture` to `last_level_temperture` (#10471)
Summary:
Change tiered compaction feature from `bottommost_temperture` to
`last_level_temperture`. The old option is kept for migration purpose only,
which is behaving the same as `last_level_temperture` and it will be removed in
the next release.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10471

Test Plan: CI

Reviewed By: siying

Differential Revision: D38450621

Pulled By: jay-zhuang

fbshipit-source-id: cc1cdf8bad409376fec0152abc0a64fb72a91527
2022-08-08 14:36:34 -07:00
Gang Liao ec4ebeff30 Support prepopulating/warming the blob cache (#10298)
Summary:
Many workloads have temporal locality, where recently written items are read back in a short period of time. When using remote file systems, this is inefficient since it involves network traffic and higher latencies. Because of this, we would like to support prepopulating the blob cache during flush.

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

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10298

Reviewed By: ltamasi

Differential Revision: D37908743

Pulled By: gangliao

fbshipit-source-id: 9feaed234bc719d38f0c02975c1ad19fa4bb37d1
2022-07-17 07:13:59 -07:00
Jay Zhuang a3acf2ef87 Add seqno to time mapping (#10338)
Summary:
Which will be used for tiered storage to preclude hot data from
compacting to the cold tier (the last level).
Internally, adding seqno to time mapping. A periodic_task is scheduled
to record the current_seqno -> current_time in certain cadence. When
memtable flush, the mapping informaiton is stored in sstable property.
During compaction, the mapping information are merged and get the
approximate time of sequence number, which is used to determine if a key
is recently inserted or not and preclude it from the last level if it's
recently inserted (within the `preclude_last_level_data_seconds`).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10338

Test Plan: CI

Reviewed By: siying

Differential Revision: D37810187

Pulled By: jay-zhuang

fbshipit-source-id: 6953be7a18a99de8b1cb3b162d712f79c2b4899f
2022-07-14 21:49:34 -07:00
Baptiste Lemaire 5879053fd0 Dynamically changeable `MemPurge` option (#10011)
Summary:
**Summary**
Make the mempurge option flag a Mutable Column Family option flag. Therefore, the mempurge feature can be dynamically toggled.

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

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

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

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

Reviewed By: pdillinger

Differential Revision: D36462357

Pulled By: bjlemaire

fbshipit-source-id: 5e3d63bdadf085c0572ecc2349e7dd9729ce1802
2022-06-23 09:42:18 -07:00
Gang Liao cba398df8a Add blob cache option in the column family options (#10155)
Summary:
There is currently no caching mechanism for blobs, which is not ideal especially when the database resides on remote storage (where we cannot rely on the OS page cache). As part of this task, we would like to make it possible for the application to configure a blob cache.
This PR is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10155

Reviewed By: ltamasi

Differential Revision: D37150819

Pulled By: gangliao

fbshipit-source-id: b807c7916ea5d411588128f8e22a49f171388fe2
2022-06-14 14:19:26 -07:00
Gang Liao e6432dfd4c Make it possible to enable blob files starting from a certain LSM tree level (#10077)
Summary:
Currently, if blob files are enabled (i.e. `enable_blob_files` is true), large values are extracted both during flush/recovery (when SST files are written into level 0 of the LSM tree) and during compaction into any LSM tree level. For certain use cases that have a mix of short-lived and long-lived values, it might make sense to support extracting large values only during compactions whose output level is greater than or equal to a specified LSM tree level (e.g. compactions into L1/L2/... or above). This could reduce the space amplification caused by large values that are turned into garbage shortly after being written at the price of some write amplification incurred by long-lived values whose extraction to blob files is delayed.

In order to achieve this, we would like to do the following:
- Add a new configuration option `blob_file_starting_level` (default: 0) to `AdvancedColumnFamilyOptions` (and `MutableCFOptions` and extend the related logic)
- Instantiate `BlobFileBuilder` in `BuildTable` (used during flush and recovery, where the LSM tree level is L0) and `CompactionJob` iff `enable_blob_files` is set and the LSM tree level is `>= blob_file_starting_level`
- Add unit tests for the new functionality, and add the new option to our stress tests (`db_stress` and `db_crashtest.py` )
- Add the new option to our benchmarking tool `db_bench` and the BlobDB benchmark script `run_blob_bench.sh`
- Add the new option to the `ldb` tool (see https://github.com/facebook/rocksdb/wiki/Administration-and-Data-Access-Tool)
- Ideally extend the C and Java bindings with the new option
- Update the BlobDB wiki to document the new option.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10077

Reviewed By: ltamasi

Differential Revision: D36884156

Pulled By: gangliao

fbshipit-source-id: 942bab025f04633edca8564ed64791cb5e31627d
2022-06-02 20:04:33 -07:00
Jay Zhuang 36aec94d85 `compression_per_level` should be used for flush and changeable (#9658)
Summary:
- Make `compression_per_level` dynamical changeable with `SetOptions`;
- Fix a bug that `compression_per_level` is not used for flush;

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9658

Test Plan: CI

Reviewed By: ajkr

Differential Revision: D34700749

Pulled By: jay-zhuang

fbshipit-source-id: a23b9dfa7ad03d393c1d71781d19e91de796f49c
2022-03-07 18:06:19 -08:00
Jay Zhuang 961d8dacf2 Remove unused option purge_redundant_kvs_while_flush (#9429)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/9429

Test Plan: fake release for test: D33754513

Reviewed By: riversand963

Differential Revision: D33753637

Pulled By: jay-zhuang

fbshipit-source-id: 18db4701e8f28dda8f1ab660c2be9890a8312c12
2022-01-26 10:24:16 -08:00
Levi Tamasi dc5de45af8 Support readahead during compaction for blob files (#9187)
Summary:
The patch adds a new BlobDB configuration option `blob_compaction_readahead_size`
that can be used to enable prefetching data from blob files during compaction.
This is important when using storage with higher latencies like HDDs or remote filesystems.
If enabled, prefetching is used for all cases when blobs are read during compaction,
namely garbage collection, compaction filters (when the existing value has to be read from
a blob file), and `Merge` (when the value of the base `Put` is stored in a blob file).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9187

Test Plan: Ran `make check` and the stress/crash test.

Reviewed By: riversand963

Differential Revision: D32565512

Pulled By: ltamasi

fbshipit-source-id: 87be9cebc3aa01cc227bec6b5f64d827b8164f5d
2021-11-19 17:53:47 -08:00
Levi Tamasi 3e1bf771a3 Make it possible to force the garbage collection of the oldest blob files (#8994)
Summary:
The current BlobDB garbage collection logic works by relocating the valid
blobs from the oldest blob files as they are encountered during compaction,
and cleaning up blob files once they contain nothing but garbage. However,
with sufficiently skewed workloads, it is theoretically possible to end up in a
situation when few or no compactions get scheduled for the SST files that contain
references to the oldest blob files, which can lead to increased space amp due
to the lack of GC.

In order to efficiently handle such workloads, the patch adds a new BlobDB
configuration option called `blob_garbage_collection_force_threshold`,
which signals to BlobDB to schedule targeted compactions for the SST files
that keep alive the oldest batch of blob files if the overall ratio of garbage in
the given blob files meets the threshold *and* all the given blob files are
eligible for GC based on `blob_garbage_collection_age_cutoff`. (For example,
if the new option is set to 0.9, targeted compactions will get scheduled if the
sum of garbage bytes meets or exceeds 90% of the sum of total bytes in the
oldest blob files, assuming all affected blob files are below the age-based cutoff.)
The net result of these targeted compactions is that the valid blobs in the oldest
blob files are relocated and the oldest blob files themselves cleaned up (since
*all* SST files that rely on them get compacted away).

These targeted compactions are similar to periodic compactions in the sense
that they force certain SST files that otherwise would not get picked up to undergo
compaction and also in the sense that instead of merging files from multiple levels,
they target a single file. (Note: such compactions might still include neighboring files
from the same level due to the need of having a "clean cut" boundary but they never
include any files from any other level.)

This functionality is currently only supported with the leveled compaction style
and is inactive by default (since the default value is set to 1.0, i.e. 100%).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8994

Test Plan: Ran `make check` and tested using `db_bench` and the stress/crash tests.

Reviewed By: riversand963

Differential Revision: D31489850

Pulled By: ltamasi

fbshipit-source-id: 44057d511726a0e2a03c5d9313d7511b3f0c4eab
2021-10-11 18:03:01 -07:00
mrambacher 78e82410eb Added static methods for simple types to OptionTypeInfo (#8249)
Summary:
Added ParseType, SerializeType, and TypesAreEqual methods to OptionTypeInfo.  These methods can be used for serialization and deserialization of basic types.

Change the MutableCF/DB Options to use this format.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8249

Reviewed By: jay-zhuang

Differential Revision: D28351190

Pulled By: mrambacher

fbshipit-source-id: 72a78643b804f2f0bf59c32ffefa63346672ad16
2021-05-11 16:15:47 -07:00
mrambacher 8948dc8524 Make ImmutableOptions struct that inherits from ImmutableCFOptions and ImmutableDBOptions (#8262)
Summary:
The ImmutableCFOptions contained a bunch of fields that belonged to the ImmutableDBOptions.  This change cleans that up by introducing an ImmutableOptions struct.  Following the pattern of Options struct, this class inherits from the DB and CFOption structs (of the Immutable form).

Only one structural change (the ImmutableCFOptions::fs was changed to a shared_ptr from a raw one) is in this PR.  All of the other changes involve moving the member variables from the ImmutableCFOptions into the ImmutableOptions and changing member variables or function parameters as required for compilation purposes.

Follow-on PRs may do a further clean-up of the code, such as renaming variables (such as "ImmutableOptions cf_options") and potentially eliminating un-needed function parameters (there is no longer a need to pass both an ImmutableDBOptions and an ImmutableOptions to a function).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8262

Reviewed By: pdillinger

Differential Revision: D28226540

Pulled By: mrambacher

fbshipit-source-id: 18ae71eadc879dedbe38b1eb8e6f9ff5c7147dbf
2021-05-05 14:00:17 -07:00
sdong c3ff14e2c1 Hint temperature of bottommost level files to FileSystem (#8222)
Summary:
As the first part of the effort of having placing different files on different storage types, this change introduces several things:
(1) An experimental interface in FileSystem that specify temperature to a new file created.
(2) A test FileSystemWrapper,  SimulatedHybridFileSystem, that simulates HDD for a file of "warm" temperature.
(3) A simple experimental feature ColumnFamilyOptions.bottommost_temperature. RocksDB would pass this value to FileSystem when creating any bottommost file.
(4) A db_bench parameter that applies the (2) and (3) to db_bench.

The motivation of the change is to introduce minimal changes that allow us to evolve tiered storage development.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8222

Test Plan:
./db_bench --benchmarks=fillrandom --write_buffer_size=2000000 -max_bytes_for_level_base=20000000  -level_compaction_dynamic_level_bytes --reads=100 -compaction_readahead_size=20000000 --reads=100000 -num=10000000

followed by

./db_bench --benchmarks=readrandom,stats --write_buffer_size=2000000 -max_bytes_for_level_base=20000000 -simulate_hybrid_fs_file=/tmp/warm_file_list -level_compaction_dynamic_level_bytes -compaction_readahead_size=20000000 --reads=500 --threads=16 -use_existing_db --num=10000000

and see results as expected.

Reviewed By: ajkr

Differential Revision: D28003028

fbshipit-source-id: 4724896d5205730227ba2f17c3fecb11261744ce
2021-05-03 13:34:04 -07:00
mrambacher 0ca6d6297f Rename variables in ImmutableCFOptions to avoid conflicts with ImmutableDBOptions (#8227)
Summary:
Renaming ImmutableCFOptions::info_log and statistics to logger and stats.  This is stage 2 in creating an ImmutableOptions class.  It is necessary because the names match those in ImmutableOptions and have different types.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8227

Reviewed By: jay-zhuang

Differential Revision: D28000967

Pulled By: mrambacher

fbshipit-source-id: 3bf2aa04e8f1e8724d825b7deacf41080c14420b
2021-04-26 12:43:45 -07:00
mrambacher 01e460d538 Make types of Immutable/Mutable Options fields match that of the underlying Option (#8176)
Summary:
This PR is a first step at attempting to clean up some of the Mutable/Immutable Options code.  With this change, a DBOption and a ColumnFamilyOption can be reconstructed from their Mutable and Immutable equivalents, respectively.

readrandom tests do not show any performance degradation versus master (though both are slightly slower than the current 6.19 release).

There are still fields in the ImmutableCFOptions that are not CF options but DB options.  Eventually, I would like to move those into an ImmutableOptions (= ImmutableDBOptions+ImmutableCFOptions).  But that will be part of a future PR to minimize changes and disruptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8176

Reviewed By: pdillinger

Differential Revision: D27954339

Pulled By: mrambacher

fbshipit-source-id: ec6b805ba9afe6e094bffdbd76246c2d99aa9fad
2021-04-22 20:43:54 -07:00
mrambacher 3dff28cf9b Use SystemClock* instead of std::shared_ptr<SystemClock> in lower level routines (#8033)
Summary:
For performance purposes, the lower level routines were changed to use a SystemClock* instead of a std::shared_ptr<SystemClock>.  The shared ptr has some performance degradation on certain hardware classes.

For most of the system, there is no risk of the pointer being deleted/invalid because the shared_ptr will be stored elsewhere.  For example, the ImmutableDBOptions stores the Env which has a std::shared_ptr<SystemClock> in it.  The SystemClock* within the ImmutableDBOptions is essentially a "short cut" to gain access to this constant resource.

There were a few classes (PeriodicWorkScheduler?) where the "short cut" property did not hold.  In those cases, the shared pointer was preserved.

Using db_bench readrandom perf_level=3 on my EC2 box, this change performed as well or better than 6.17:

6.17: readrandom   :      28.046 micros/op 854902 ops/sec;   61.3 MB/s (355999 of 355999 found)
6.18: readrandom   :      32.615 micros/op 735306 ops/sec;   52.7 MB/s (290999 of 290999 found)
PR: readrandom   :      27.500 micros/op 871909 ops/sec;   62.5 MB/s (367999 of 367999 found)

(Note that the times for 6.18 are prior to revert of the SystemClock).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8033

Reviewed By: pdillinger

Differential Revision: D27014563

Pulled By: mrambacher

fbshipit-source-id: ad0459eba03182e454391b5926bf5cdd45657b67
2021-03-15 04:34:11 -07:00
Zhichao Cao d1c510baec Handoff checksum Implementation (#7523)
Summary:
in PR https://github.com/facebook/rocksdb/issues/7419 , we introduce the new Append and PositionedAppend APIs to WritableFile at File System, which enable RocksDB to pass the data verification information (e.g., checksum of the data) to the lower layer. In this PR, we use the new API in WritableFileWriter, such that the file created via WritableFileWrite can pass the checksum to the storage layer. To control which types file should apply the checksum handoff, we add checksum_handoff_file_types to DBOptions. User can use this option to control which file types (Currently supported file tyes: kLogFile, kTableFile, kDescriptorFile.) should use the new Append and PositionedAppend APIs to handoff the verification information.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7523

Test Plan: add new unit test, pass make check/ make asan_check

Reviewed By: pdillinger

Differential Revision: D24313271

Pulled By: zhichao-cao

fbshipit-source-id: aafd69091ae85c3318e3e17cbb96fe7338da11d0
2021-02-10 22:20:32 -08:00
Levi Tamasi bbbb5a280d Add options for integrated blob GC (#7661)
Summary:
This patch simply adds a couple of options that will enable users to
configure garbage collection when using the integrated BlobDB
implementation. The actual GC logic will be added in a separate step.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7661

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D24906544

Pulled By: ltamasi

fbshipit-source-id: ee0e056a712a4b4475cd90de8b27d969bd61b7e1
2020-11-12 18:58:44 -08:00
anand76 00751e4292 Add a host location property to TableProperties (#7479)
Summary:
This PR adds support for writing a location identifier of the DB host to SST files as a table property. By default, the hostname is used, but can be overridden by the user. There have been some recent corruptions in files written by ```SstFileWriter``` before checksumming, so this property can be used to trace it back to the writing host and checking the host for hardware isues.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7479

Test Plan: Add new unit tests

Reviewed By: pdillinger

Differential Revision: D24340671

Pulled By: anand1976

fbshipit-source-id: 2038949fd8d160c0633ccb4f9da77740f19fa2a2
2020-10-19 11:38:48 -07:00
sdong 7508175558 Introduce options.check_flush_compaction_key_order (#7467)
Summary:
Introduce an new option options.check_flush_compaction_key_order, by default set to true, which checks key order of flush and compaction, and fail the operation if the order is violated.
Also did minor refactor hash checking code, which consolidates the hashing logic to a vlidation class, where the key ordering logic is added.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7467

Test Plan: Add unit tests to validate the check can catch reordering in flush and compaction, and can be properly disabled.

Reviewed By: riversand963

Differential Revision: D24010683

fbshipit-source-id: 8dd6292d2cda8006054e9ded7cfa4bf405f0527c
2020-10-01 10:10:26 -07:00
Akanksha Mahajan 9d212d3f0e Provide users with option to opt-in to get corrupt data in logs/messages (#7420)
Summary:
Add a new Option "allow_data_in_errors". When it's set by users, it allows them to opt-in to get error messages containing corrupted keys/values. Corrupt keys, values will be logged in the messages, logs, status etc. that will help users with the useful information regarding affected data.
By default value is set false to prevent users data to be exposed in the messages.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7420

Test Plan:
1. make check -j64
           2. Add a new test case

Reviewed By: ajkr

Differential Revision: D23835028

Pulled By: akankshamahajan15

fbshipit-source-id: 8d2eba8fb898e79fcf1fccc07295065a75eb59b1
2020-09-29 23:17:45 -07:00
mrambacher 7d472accdc Bring the Configurable options together (#5753)
Summary:
This PR merges the functionality of making the ColumnFamilyOptions, TableFactory, and DBOptions into Configurable into a single PR, resolving any merge conflicts

Pull Request resolved: https://github.com/facebook/rocksdb/pull/5753

Reviewed By: ajkr

Differential Revision: D23385030

Pulled By: zhichao-cao

fbshipit-source-id: 8b977a7731556230b9b8c5a081b98e49ee4f160a
2020-09-14 17:01:01 -07:00
Levi Tamasi b9bb59d49d Add initial set of options for integrated blob write path (#7280)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/7280

Test Plan: `make check`

Reviewed By: riversand963

Differential Revision: D23195192

Pulled By: ltamasi

fbshipit-source-id: 743b382de391963e62ba86119e9fbd0233ea3b3a
2020-08-18 18:32:37 -07:00
Tomas Kolda cd4592c220 SST Partitioner interface that allows to split SST files (#6957)
Summary:
SST Partitioner interface that allows to split SST files during compactions.

It basically instruct compaction to create a new file when needed. When one is using well defined prefixes and prefixed way of defining tables it is good to define also partitioning so that promotion of some SST file does not cover huge key space on next level (worst case complete space).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/6957

Reviewed By: ajkr

Differential Revision: D22461239

fbshipit-source-id: 9ce07bba08b3ba89c2d45630520368f704d1316e
2020-07-24 13:44:49 -07:00
Jay Zhuang b0c5ecd6b3 Make max_subcompactions dynamically changeable (#7159)
Summary:
Make `max-subcompactions` dynamically changeable by passing the `DBOption` to Compaction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7159

Reviewed By: siying

Differential Revision: D22671238

Pulled By: jay-zhuang

fbshipit-source-id: 311ca9f6bb606965544d8708616d358cfed5be42
2020-07-22 18:32:52 -07:00
Andrew Kryczka 02db03af8d make L0 index/filter pinned memory usage predictable (#6911)
Summary:
Memory pinned by `pin_l0_filter_and_index_blocks_in_cache` needs to be predictable based on user config. This PR makes sure
we do not pin extra memory for large files generated by intra-L0 (see https://github.com/facebook/rocksdb/issues/6889).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6911

Test Plan: unit test

Reviewed By: siying

Differential Revision: D21835818

Pulled By: ajkr

fbshipit-source-id: a11a088549d06bed8aacc2548d266e5983f0ead4
2020-06-09 16:51:23 -07:00
sdong 80979f81c7 Make options.bottommost_compression, compression_opts and bottommost_compression_opts dynamically changeable. (#6615)
Summary:
These three options should be made dynamically changeable. Simply add them to MutableCFOptions and made the change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6615

Test Plan: Add a unit test to make sure that SetOptions() can change the options.

Reviewed By: riversand963

Differential Revision: D20755951

fbshipit-source-id: 8165f4fd7a7a665cc7fb049698935022a5d2e7ff
2020-03-31 12:11:42 -07:00
Zhichao Cao e8d332d97e Use FileChecksumGenFactory for SST file checksum (#6600)
Summary:
In the current implementation, sst file checksum is calculated by a shared checksum function object, which may make some checksum function hard to be applied here such as SHA1. In this implementation, each sst file will have its own checksum generator obejct, created by FileChecksumGenFactory. User needs to implement its own FilechecksumGenerator and Factory to plugin the in checksum calculation method.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6600

Test Plan: tested with make asan_check

Reviewed By: riversand963

Differential Revision: D20717670

Pulled By: zhichao-cao

fbshipit-source-id: 2a74c1c280ac11a07a1980185b43b671acaa71c6
2020-03-29 15:58:46 -07:00
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
anand76 afa2420c2b Introduce a new storage specific Env API (#5761)
Summary:
The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc.

This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO.

The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before.

This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection.

The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761

Differential Revision: D18868376

Pulled By: anand1976

fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 14:48:41 -08:00
Peter Dillinger 4f17d33db4 Remove unused/undefined ImmutableCFOptions() (#6086)
Summary:
default constructor not used or even defined
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6086

Differential Revision: D18695669

Pulled By: pdillinger

fbshipit-source-id: 6b6ac46029f4fb6edf1c11ee6ce1d9f172b2eaf2
2019-11-26 13:28:31 -08:00
Maysam Yabandeh 6ec6a4a9a4 Remove snap_refresh_nanos option (#5826)
Summary:
The snap_refresh_nanos option didn't bring much benefit. Remove the feature to simplify the code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5826

Differential Revision: D17467147

Pulled By: maysamyabandeh

fbshipit-source-id: 4f950b046990d0d1292d7fc04c2ccafaf751c7f0
2019-09-18 20:26:04 -07:00
Zhongyi Xie 2f41ecfe75 Refactor trimming logic for immutable memtables (#5022)
Summary:
MyRocks currently sets `max_write_buffer_number_to_maintain` in order to maintain enough history for transaction conflict checking. The effectiveness of this approach depends on the size of memtables. When memtables are small, it may not keep enough history; when memtables are large, this may consume too much memory.
We are proposing a new way to configure memtable list history: by limiting the memory usage of immutable memtables. The new option is `max_write_buffer_size_to_maintain` and it will take precedence over the old `max_write_buffer_number_to_maintain` if they are both set to non-zero values. The new option accounts for the total memory usage of flushed immutable memtables and mutable memtable. When the total usage exceeds the limit, RocksDB may start dropping immutable memtables (which is also called trimming history), starting from the oldest one.
The semantics of the old option actually works both as an upper bound and lower bound. History trimming will start if number of immutable memtables exceeds the limit, but it will never go below (limit-1) due to history trimming.
In order the mimic the behavior with the new option, history trimming will stop if dropping the next immutable memtable causes the total memory usage go below the size limit. For example, assuming the size limit is set to 64MB, and there are 3 immutable memtables with sizes of 20, 30, 30. Although the total memory usage is 80MB > 64MB, dropping the oldest memtable will reduce the memory usage to 60MB < 64MB, so in this case no memtable will be dropped.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5022

Differential Revision: D14394062

Pulled By: miasantreble

fbshipit-source-id: 60457a509c6af89d0993f988c9b5c2aa9e45f5c5
2019-08-23 13:55:34 -07:00