Commit Graph

976 Commits

Author SHA1 Message Date
mrambacher
570248aeff Make SecondaryCache Customizable (#8480)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8480

Reviewed By: zhichao-cao

Differential Revision: D29528740

Pulled By: mrambacher

fbshipit-source-id: fd0f70d15f66611c8498257a9973f7e98ca13839
2021-07-06 09:18:08 -07:00
Akanksha Mahajan
c76778e2bd Call OnCompactionCompleted API in case of DisableManualCompaction (#8469)
Summary:
Call OnCompactionCompleted API in case of
DisableManualCompaction() with updated Status::Incomplete

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8469

Reviewed By: ajkr

Differential Revision: D29475517

Pulled By: akankshamahajan15

fbshipit-source-id: a1726c5e6ee18c0b5097ea04f5e6975fbe108055
2021-07-01 19:18:55 -07:00
Jay Zhuang
93a7389442 Add statistics support on CompactionService remote side (#8368)
Summary:
Add statistics option on CompactionService remote side.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8368

Test Plan: `make check`

Reviewed By: ajkr

Differential Revision: D28944427

Pulled By: jay-zhuang

fbshipit-source-id: 2a19217f4a69b6e511af87eed12391860ef00c5e
2021-06-29 11:48:14 -07:00
mrambacher
89f66d4484 Add customizable_util.h to the public API (#8301)
Summary:
Useful for allowing new classes to create and manage Customizable objects without using internal APIs.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8301

Reviewed By: zhichao-cao

Differential Revision: D29428303

Pulled By: mrambacher

fbshipit-source-id: 3d33d5197cc8379fe35b54d3d169f91f0dfe7a47
2021-06-29 09:08:57 -07:00
mrambacher
be219089ad Add BlobMetaData retrieval methods (#8273)
Summary:
Added BlobMetaData to ColumnFamilyMetaData and LiveBlobMetaData and DB API GetLiveBlobMetaData to retrieve it.

First pass at struct.  More tests and maybe fields to come...

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8273

Reviewed By: ltamasi

Differential Revision: D29102400

Pulled By: mrambacher

fbshipit-source-id: 8a2383a4446328be6b91dced9841fdd3dfc80b73
2021-06-28 08:13:29 -07:00
Akanksha Mahajan
be8199cdb9 Run Merge with Integrated BlobDB in stress, crash and db_bench (#8461)
Summary:
Run Merge with Intergrated BlobDB in stress tests, crash tests and db_bench.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8461

Test Plan:
1. python3 -u tools/db_crashtest.py --simple whitebox
---use_merge=1 --enable_blob_files=1
           2.  ./db_bench --benchmarks="readwhilemerging"
--merge_operator=uint64add --enable_blob_files=true

Reviewed By: ltamasi

Differential Revision: D29394824

Pulled By: akankshamahajan15

fbshipit-source-id: 0a8e492b13129673e088fb8af3402ab678bb473a
2021-06-25 10:45:52 -07:00
Andrew Kryczka
3d844dff1d add missing fields to GetLiveFilesMetaData() (#8460)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8460

Reviewed By: jay-zhuang

Differential Revision: D29381865

Pulled By: ajkr

fbshipit-source-id: 47ba54c25f3cc039d72ea32e1df20875795683b3
2021-06-24 21:05:03 -07:00
Levi Tamasi
66b62a123a Update HISTORY.md for PR 8450 (#8458)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8458

Reviewed By: zhichao-cao

Differential Revision: D29378728

Pulled By: ltamasi

fbshipit-source-id: d5a40b1414500f53823763be5c2bfce8db04daf8
2021-06-24 17:26:32 -07:00
Baptiste Lemaire
3f20925dc4 Add list live files metadata (#8446)
Summary:
Add an argument to ldb to dump live file names, column families, and levels, `list_live_files_metadata`. The output shows all active SST file names, sorted first by column family and then by level. For each level the SST files are sorted alphabetically.

Typically, the output looks like this:
```
./ldb --db=/tmp/test_db list_live_files_metadata
Live SST Files:
===== Column Family: default =====
---------- level 0 ----------
/tmp/test_db/000069.sst
---------- level 1 ----------
/tmp/test_db/000064.sst
/tmp/test_db/000065.sst
/tmp/test_db/000066.sst
/tmp/test_db/000071.sst
---------- level 2 ----------
/tmp/test_db/000038.sst
/tmp/test_db/000039.sst
/tmp/test_db/000052.sst
/tmp/test_db/000067.sst
/tmp/test_db/000070.sst
------------------------------
```

Second, a flag was added `--sort_by_filename`, to change the layout of the output. When this flag is added to the command, the output shows all active SST files sorted by name, in front of which the LSM level and the column family are mentioned. With the same example, the following command would return:
```
./ldb --db=/tmp/test_db list_live_files_metadata --sort_by_filename
Live SST Files:
/tmp/test_db/000038.sst : level 2, column family 'default'
/tmp/test_db/000039.sst : level 2, column family 'default'
/tmp/test_db/000052.sst : level 2, column family 'default'
/tmp/test_db/000064.sst : level 1, column family 'default'
/tmp/test_db/000065.sst : level 1, column family 'default'
/tmp/test_db/000066.sst : level 1, column family 'default'
/tmp/test_db/000067.sst : level 2, column family 'default'
/tmp/test_db/000069.sst : level 0, column family 'default'
/tmp/test_db/000070.sst : level 2, column family 'default'
/tmp/test_db/000071.sst : level 1, column family 'default'
------------------------------
```

Thus, the user can either request to show the files by levels, or sorted by filenames.
This PR includes a simple Python unit test that makes sure the file name and level printed out by this new feature matches the one found with an existing feature, `dump_live_file`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8446

Reviewed By: akankshamahajan15

Differential Revision: D29320080

Pulled By: bjlemaire

fbshipit-source-id: 01fb7b5637c59010d74c80730a28d815994e7009
2021-06-22 19:07:46 -07:00
Levi Tamasi
005c046734 Update HISTORY.md for PR 8437 (#8442)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8442

Reviewed By: akankshamahajan15

Differential Revision: D29306432

Pulled By: ltamasi

fbshipit-source-id: 0fe55736368ac024b2f51213b65f4b06d71d60e6
2021-06-22 13:37:22 -07:00
Jay Zhuang
f89423a57a Revert "Revert "Snapshot release triggered compaction without multiple tombstones (#8357)" (#8410)" (#8438)
Summary:
This reverts commit 25be1ed66a.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8438

Test Plan: Run the impacted mysql test 40 times

Reviewed By: ajkr

Differential Revision: D29286247

Pulled By: jay-zhuang

fbshipit-source-id: d3bd056971a19a8b012d5d0295fa045c012b3c04
2021-06-22 11:10:03 -07:00
Andrew Kryczka
b511b042f4 Fixup HISTORY.md for 6.22 release (#8441)
Summary:
`git diff origin/6.21.fb origin/6.22.fb -- HISTORY.md` looked odd.
This PR fixes it up by moving items from 6.21.0 to 6.22.0 that were
never in any 6.21 release. Also mentioned the background stat collection
fix under 6.22 (previously it was mentioned under 6.21 patch releases
only).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8441

Reviewed By: jay-zhuang

Differential Revision: D29304812

Pulled By: ajkr

fbshipit-source-id: 2a928a9518a1d6615321d5c2d1e22b17cbb59093
2021-06-22 10:30:10 -07:00
Jay Zhuang
54d73d6429 Fix DeleteFilesInRange may cause inconsistent compaction error (#8434)
Summary:
`DeleteFilesInRange()` marks deleting files to `being_compacted`
before deleting, which may cause ongoing compactions report corruption
exception or ASSERT for debug build.

Adding the missing `ComputeCompactionScore()` when `being_compacted` is set.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8434

Test Plan: Unittest

Reviewed By: ajkr

Differential Revision: D29276127

Pulled By: jay-zhuang

fbshipit-source-id: f5b223e3c1fc6d821e100e3f3442bc70c1d50cf7
2021-06-22 09:17:37 -07:00
Andrew Kryczka
7ed69fbe72 Update HISTORY.md and version.h 6.22 release (#8427)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8427

Reviewed By: zhichao-cao

Differential Revision: D29246916

Pulled By: ajkr

fbshipit-source-id: ccd44ca1a6dd5101dc37f19b8e1fe6c0e3883e0a
2021-06-19 12:12:46 -07:00
Baptiste Lemaire
e817bc9628 Added memtable garbage statistics (#8411)
Summary:
**Summary**:
2 new statistics counters are added to RocksDB: `MEMTABLE_PAYLOAD_BYTES_AT_FLUSH` and `MEMTABLE_GARBAGE_BYTES_AT_FLUSH`. The former tracks how many raw bytes of useful data are present on the memtable at flush time, whereas the latter is tracks how many of these raw bytes are considered garbage, meaning that they ended up not being imported on the SSTables resulting from the flush operations.

**Unit test**: run `make db_flush_test -j$(nproc); ./db_flush_test` to run the unit test.
This executable includes 3 tests, that test support and correct stat calculations for workloads with inserts, deletes, and DeleteRanges. The parameters are set such that the workloads are performed on a single memtable, and a single SSTable is created as a result of the flush operation. The flush operation is manually called in the test file. The tests verify that the values of these 2 statistics counters introduced in this PR  can be exactly predicted, showing that we have a full understanding of the underlying operations.

**Performance testing**:
`./db_bench -statistics -benchmarks=fillrandom -num=10000000` repeated 10 times.
Timing done using "date" function in a bash script.
_Results_:
Original Rocksdb fork: mean 66.6 sec, std 1.18 sec.
This feature branch: mean 67.4 sec, std 1.35 sec.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8411

Reviewed By: akankshamahajan15

Differential Revision: D29150629

Pulled By: bjlemaire

fbshipit-source-id: 7b3c2e86d50c6aa34fa50fd134282eacb543a5b1
2021-06-18 04:57:27 -07:00
Akanksha Mahajan
5ba1b6e549 Cache warming data blocks during flush (#8242)
Summary:
This PR prepopulates warm/hot data blocks which are already in memory
into block cache at the time of flush. On a flush, the data block that is
in memory (in memtables) get flushed to the device. If using Direct IO,
additional IO is incurred to read this data back into memory again, which
is avoided by enabling newly added option.

 Right now, this is enabled only for flush for data blocks. We plan to
expand this option to cover compactions in the future and for other types
 of blocks.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8242

Test Plan: Add new unit test

Reviewed By: anand1976

Differential Revision: D28521703

Pulled By: akankshamahajan15

fbshipit-source-id: 7219d6958821cedce689a219c3963a6f1a9d5f05
2021-06-17 21:56:47 -07:00
聂佩轩
d53f7ff69a Add DeteleRange support for DBWithTTL (#8384)
Summary:
This commit is for enabling `DBWithTTL` to use `DeteleRange` which it cannot before.
As (int32_t)Timestamp is suffixed to values in `DBWithTTL`, there is no reason that it
cannot use the common used api. I added `DeleteRangeCF` in `DBWithTTLImpl::Write`
so that we can use `DeteleRange` normally. When we run code like
`dbWithTtl->DeleteRange(start, end)`, it executes`WriteBatchInternal::DeleteRange`
internally. Intended to fix https://github.com/facebook/rocksdb/issues/7218

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8384

Test Plan: added corresponded testing logic to existing unit test

Reviewed By: jay-zhuang

Differential Revision: D29176734

fbshipit-source-id: 6874ed979fc08e1d138149d03653e43a75f0e0e6
2021-06-17 16:00:50 -07:00
Peter Dillinger
865a25101d Mark Ribbon filter and optimize_filters_for_memory as production (#8408)
Summary:
Marked the Ribbon filter and optimize_filters_for_memory features
as production-ready, each enabling memory savings for Bloom-like filters.
Use `NewRibbonFilterPolicy` in place of `NewBloomFilterPolicy` to use
Ribbon filters instead of Bloom, or `ribbonfilter` in place of
`bloomfilter` in configuration string.

Some small refactoring in db_stress.

Removed/refactored unused code in db_bench, in part preparing for future
default possibly being different from "disabled."

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8408

Test Plan:
Lots of prior automated, ad-hoc, and "real world" testing.
Updated tests for new API names. Quick db_bench test:

bloom fillrandom
77730 ops/sec
rocksdb.block.cache.filter.bytes.insert COUNT : 89929384

ribbon fillrandom
71492 ops/sec
rocksdb.block.cache.filter.bytes.insert COUNT : 64531384

Reviewed By: mrambacher

Differential Revision: D29140805

Pulled By: pdillinger

fbshipit-source-id: d742c922722421678f95ad85eeb0aaebc9f5e49a
2021-06-17 12:29:16 -07:00
Andrew Kryczka
25be1ed66a Revert "Snapshot release triggered compaction without multiple tombstones (#8357)" (#8410)
Summary:
This reverts commit 9167ece586.

It was found to reliably trip a compaction picking conflict assertion in a MyRocks unit test. We don't understand why yet so reverting in the meantime.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8410

Test Plan: `make check -j48`

Reviewed By: jay-zhuang

Differential Revision: D29150300

Pulled By: ajkr

fbshipit-source-id: 2de8664f355d6da015e84e5fec2e3f90f49741c8
2021-06-15 18:15:15 -07:00
Levi Tamasi
146263887f Disable subcompactions for user-defined timestamps (#8393)
Summary:
The subcompaction boundary picking logic does not currently guarantee
that all user keys that differ only by timestamp get processed by the same
subcompaction. This can cause issues with the `CompactionIterator` state
machine: for instance, one subcompaction that processes a subset of such KVs
might drop a tombstone based on the KVs it sees, while in reality the
tombstone might not have been eligible to be optimized out.
(See also https://github.com/facebook/rocksdb/issues/6645, which adjusted the way compaction inputs are picked for the
same reason.)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8393

Test Plan: Ran `make check` and the crash test script with timestamps enabled.

Reviewed By: jay-zhuang

Differential Revision: D29071635

Pulled By: ltamasi

fbshipit-source-id: f6c72442122b4e581871e096fabe3876a9e8a5a6
2021-06-12 12:09:25 -07:00
Peter Dillinger
b3dbeadc34 Fix double-dumping CF stats to log (#8380)
Summary:
DBImpl::DumpStats is supposed to do this:
Dump DB stats to LOG
For each CF, dump CFStatsNoFileHistogram to LOG
For each CF, dump CFFileHistogram to LOG

Instead, due to a longstanding bug from 2017 (https://github.com/facebook/rocksdb/issues/2126), it would dump
CFStats, which includes both CFStatsNoFileHistogram and CFFileHistogram,
in both loops, resulting in near-duplicate output.

This fixes the bug.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8380

Test Plan: Manual inspection of LOG after db_bench

Reviewed By: jay-zhuang

Differential Revision: D29017535

Pulled By: pdillinger

fbshipit-source-id: 3010604c4a629a80347f129cd746ce9b0d0cbda6
2021-06-11 17:06:09 -07:00
matthewvon
5a2b4ed671 BugFix: fs_posix.cc GetFreeSpace uses wrong value non-root users (#8370)
Summary:
fs_posix.cc GetFreeSpace() calculates free space based upon a call to statvfs().  However, there are two extremely different values in statvfs's returned structure:  f_bfree which is free space for root and f_bavail which is free space for non-root users.  The existing code uses f_bfree.  Many disks have 5 to 10% of the total disk space reserved for root only.  Therefore GetFreeSpace() does not realize that non-root users may not have storage available.

This PR detects whether the effective posix user is root or not, then selects the appropriate available space value.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8370

Reviewed By: mrambacher

Differential Revision: D29032710

Pulled By: jay-zhuang

fbshipit-source-id: 57feba34ed035615a479956d28f98d85735281c0
2021-06-10 11:11:54 -07:00
David Devecsery
80a59a03a7 Cancel compact range (#8351)
Summary:
Added the ability to cancel an in-progress range compaction by storing to an atomic "canceled" variable pointed to within the CompactRangeOptions structure.

Tested via two tests added to db_tests2.cc.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8351

Reviewed By: ajkr

Differential Revision: D28808894

Pulled By: ddevec

fbshipit-source-id: cb321361c9e23b084b188bb203f11c375a22c2dd
2021-06-07 11:41:31 -07:00
Andrew Kryczka
9167ece586 Snapshot release triggered compaction without multiple tombstones (#8357)
Summary:
This is a duplicate of https://github.com/facebook/rocksdb/issues/4948 by mzhaom to fix tests after rebase.

This change is a follow-up to https://github.com/facebook/rocksdb/issues/4927, which made this possible by allowing tombstone dropping/seqnum zeroing optimizations on the last key in the compaction. Now the `largest_seqno != 0` condition suffices to prevent snapshot release triggered compaction from entering an infinite loop.

The issues caused by the extraneous condition `level_and_file.second->num_deletions > 1` are:

- files could have `largest_seqno > 0` forever making it impossible to tell they cannot contain any covering keys
- it doesn't trigger compaction when there are many overwritten keys. Some MyRocks use case actually doesn't use Delete but instead calls Put with empty value to "delete" keys, so we'd like to be able to trigger compaction in this case too.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8357

Test Plan: - make check

Reviewed By: jay-zhuang

Differential Revision: D28855340

Pulled By: ajkr

fbshipit-source-id: a261b51eecafec492499e6d01e8e43112f801798
2021-06-04 00:21:40 -07:00
anand76
799cf37cb1 Update HISTORY and version to 6.21 (#8363)
Summary:
Update HISTORY and version to 6.21 on master.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8363

Reviewed By: jay-zhuang

Differential Revision: D28888818

Pulled By: anand1976

fbshipit-source-id: 9e5fac3b99ecc9f3b7d9f21474a39fa50decb117
2021-06-03 19:32:14 -07:00
Peter Dillinger
956ce9bde2 Some API clarification for manual compaction and listeners (#8330)
Summary:
Avoid people hitting bugs

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8330

Test Plan: comments only

Reviewed By: siying

Differential Revision: D28683157

Pulled By: pdillinger

fbshipit-source-id: 2b34d3efb5e2fa34bea93d54c940cbd425212d25
2021-05-26 08:14:38 -07:00
Peter Dillinger
3469d60fcc Add table properties for number of entries added to filters (#8323)
Summary:
With Ribbon filter work and possible variance in actual bits
per key (or prefix; general term "entry") to achieve certain FP rates,
I've received a request to be able to track actual bits per key in
generated filters. This change adds a num_filter_entries table
property, which can be combined with filter_size to get bits per key
(entry).

This can vary from num_entries in at least these ways:
* Different versions of same key are only counted once in filters.
* With prefix filters, several user keys map to the same filter entry.
* A single filter can include both prefixes and user keys.

Note that FilterBlockBuilder::NumAdded() didn't do anything useful
except distinguish empty from non-empty.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8323

Test Plan: basic unit test included, others updated

Reviewed By: jay-zhuang

Differential Revision: D28596210

Pulled By: pdillinger

fbshipit-source-id: 529a111f3c84501e5a470bc84705e436ee68c376
2021-05-21 17:11:32 -07:00
Jay Zhuang
6c86543590 Fix manual compaction max_compaction_bytes under-calculated issue (#8269)
Summary:
Fix a bug that for manual compaction, `max_compaction_bytes` is only
limit the SST files from input level, but not overlapped files on output
level.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8269

Test Plan: `make check`

Reviewed By: ajkr

Differential Revision: D28231044

Pulled By: jay-zhuang

fbshipit-source-id: 9d7d03004f30cc4b1b9819830141436907554b7c
2021-05-21 14:03:44 -07:00
sdong
bd3d080ef8 Try to build with liburing by default. (#8322)
Summary:
By default, try to build with liburing. For make, if ROCKSDB_USE_IO_URING is not set, treat as 1, which means RocksDB will try to build with liburing. For cmake, add WITH_LIBURING to control it, with default on.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8322

Test Plan: Build using cmake and make.

Reviewed By: anand1976

Differential Revision: D28586498

fbshipit-source-id: cfd39159ab697f4b93a9293a59c07f839b1e7ed5
2021-05-21 10:21:53 -07:00
sdong
2f1984dd45 Compare memtable insert and flush count (#8288)
Summary:
When a memtable is flushed, it will validate number of entries it reads, and compare the number with how many entries inserted into memtable. This serves as one sanity c\
heck against memory corruption. This change will also allow more counters to be added in the future for better validation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8288

Test Plan: Pass all existing tests

Reviewed By: ajkr

Differential Revision: D28369194

fbshipit-source-id: 7ff870380c41eab7f99eee508550dcdce32838ad
2021-05-20 16:07:28 -07:00
Jay Zhuang
3786181a90 Add remote compaction public API (#8300)
Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/8300

Reviewed By: ajkr

Differential Revision: D28464726

Pulled By: jay-zhuang

fbshipit-source-id: 49e9f4fb791808a6cbf39a7b1a331373f645fc5e
2021-05-19 21:41:31 -07:00
Peter Dillinger
311a544c2a Use deleters to label cache entries and collect stats (#8297)
Summary:
This change gathers and publishes statistics about the
kinds of items in block cache. This is especially important for
profiling relative usage of cache by index vs. filter vs. data blocks.
It works by iterating over the cache during periodic stats dump
(InternalStats, stats_dump_period_sec) or on demand when
DB::Get(Map)Property(kBlockCacheEntryStats), except that for
efficiency and sharing among column families, saved data from
the last scan is used when the data is not considered too old.

The new information can be seen in info LOG, for example:

    Block cache LRUCache@0x7fca62229330 capacity: 95.37 MB collections: 8 last_copies: 0 last_secs: 0.00178 secs_since: 0
    Block cache entry stats(count,size,portion): DataBlock(7092,28.24 MB,29.6136%) FilterBlock(215,867.90 KB,0.888728%) FilterMetaBlock(2,5.31 KB,0.00544%) IndexBlock(217,180.11 KB,0.184432%) WriteBuffer(1,256.00 KB,0.262144%) Misc(1,0.00 KB,0%)

And also through DB::GetProperty and GetMapProperty (here using
ldb just for demonstration):

    $ ./ldb --db=/dev/shm/dbbench/ get_property rocksdb.block-cache-entry-stats
    rocksdb.block-cache-entry-stats.bytes.data-block: 0
    rocksdb.block-cache-entry-stats.bytes.deprecated-filter-block: 0
    rocksdb.block-cache-entry-stats.bytes.filter-block: 0
    rocksdb.block-cache-entry-stats.bytes.filter-meta-block: 0
    rocksdb.block-cache-entry-stats.bytes.index-block: 178992
    rocksdb.block-cache-entry-stats.bytes.misc: 0
    rocksdb.block-cache-entry-stats.bytes.other-block: 0
    rocksdb.block-cache-entry-stats.bytes.write-buffer: 0
    rocksdb.block-cache-entry-stats.capacity: 8388608
    rocksdb.block-cache-entry-stats.count.data-block: 0
    rocksdb.block-cache-entry-stats.count.deprecated-filter-block: 0
    rocksdb.block-cache-entry-stats.count.filter-block: 0
    rocksdb.block-cache-entry-stats.count.filter-meta-block: 0
    rocksdb.block-cache-entry-stats.count.index-block: 215
    rocksdb.block-cache-entry-stats.count.misc: 1
    rocksdb.block-cache-entry-stats.count.other-block: 0
    rocksdb.block-cache-entry-stats.count.write-buffer: 0
    rocksdb.block-cache-entry-stats.id: LRUCache@0x7f3636661290
    rocksdb.block-cache-entry-stats.percent.data-block: 0.000000
    rocksdb.block-cache-entry-stats.percent.deprecated-filter-block: 0.000000
    rocksdb.block-cache-entry-stats.percent.filter-block: 0.000000
    rocksdb.block-cache-entry-stats.percent.filter-meta-block: 0.000000
    rocksdb.block-cache-entry-stats.percent.index-block: 2.133751
    rocksdb.block-cache-entry-stats.percent.misc: 0.000000
    rocksdb.block-cache-entry-stats.percent.other-block: 0.000000
    rocksdb.block-cache-entry-stats.percent.write-buffer: 0.000000
    rocksdb.block-cache-entry-stats.secs_for_last_collection: 0.000052
    rocksdb.block-cache-entry-stats.secs_since_last_collection: 0

Solution detail - We need some way to flag what kind of blocks each
entry belongs to, preferably without changing the Cache API.
One of the complications is that Cache is a general interface that could
have other users that don't adhere to whichever convention we decide
on for keys and values. Or we would pay for an extra field in the Handle
that would only be used for this purpose.

This change uses a back-door approach, the deleter, to indicate the
"role" of a Cache entry (in addition to the value type, implicitly).
This has the added benefit of ensuring proper code origin whenever we
recognize a particular role for a cache entry; if the entry came from
some other part of the code, it will use an unrecognized deleter, which
we simply attribute to the "Misc" role.

An internal API makes for simple instantiation and automatic
registration of Cache deleters for a given value type and "role".

Another internal API, CacheEntryStatsCollector, solves the problem of
caching the results of a scan and sharing them, to ensure scans are
neither excessive nor redundant so as not to harm Cache performance.

Because code is added to BlocklikeTraits, it is pulled out of
block_based_table_reader.cc into its own file.

This is a reformulation of https://github.com/facebook/rocksdb/issues/8276, without the type checking option
(could still be added), and with actual stat gathering.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8297

Test Plan: manual testing with db_bench, and a couple of basic unit tests

Reviewed By: ltamasi

Differential Revision: D28488721

Pulled By: pdillinger

fbshipit-source-id: 472f524a9691b5afb107934be2d41d84f2b129fb
2021-05-19 16:51:13 -07:00
anand76
9d61a0856d Sync ingested files only if reopen is supported by the FS (#8296)
Summary:
Some file systems (especially distributed FS) do not support reopening a file for writing. The ExternalSstFileIngestionJob calls ReopenWritableFile in order to sync the ingested file, which typically makes sense only on a local file system with a page cache (i.e Posix). So this change tries to sync the ingested file only if ReopenWritableFile doesn't return Status::NotSupported().

Tests:
Add a new unit test in external_sst_file_basic_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8296

Reviewed By: jay-zhuang

Differential Revision: D28420865

Pulled By: anand1976

fbshipit-source-id: 380e7f5ff95324997f7a59864a9ac96ebbd0100c
2021-05-18 19:33:55 -07:00
sdong
60e5af83c1 Handle return code by io_uring_submit_and_wait() and io_uring_wait_cqe() (#8311)
Summary:
Right now return codes by io_uring_submit_and_wait() and io_uring_wait_cqe() are not handled. It is not the good practice. Although these two functions are not supposed to return non-0 values in normal exeuction, people suspect that they might return non-0 value when an interruption happens, and the code might cause hanging.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8311

Test Plan: Make sure at least normal test cases still pass.

Reviewed By: anand1976

Differential Revision: D28500828

fbshipit-source-id: 8a76cea9cafbd041102e0b6a8eef9d0bfed7c211
2021-05-18 16:09:14 -07:00
Peter Dillinger
78a309bf86 New Cache API for gathering statistics (#8225)
Summary:
Adds a new Cache::ApplyToAllEntries API that we expect to use
(in follow-up PRs) for efficiently gathering block cache statistics.
Notable features vs. old ApplyToAllCacheEntries:

* Includes key and deleter (in addition to value and charge). We could
have passed in a Handle but then more virtual function calls would be
needed to get the "fields" of each entry. We expect to use the 'deleter'
to identify the origin of entries, perhaps even more.
* Heavily tuned to minimize latency impact on operating cache. It
does this by iterating over small sections of each cache shard while
cycling through the shards.
* Supports tuning roughly how many entries to operate on for each
lock acquire and release, to control the impact on the latency of other
operations without excessive lock acquire & release. The right balance
can depend on the cost of the callback. Good default seems to be
around 256.
* There should be no need to disable thread safety. (I would expect
uncontended locks to be sufficiently fast.)

I have enhanced cache_bench to validate this approach:

* Reports a histogram of ns per operation, so we can look at the
ditribution of times, not just throughput (average).
* Can add a thread for simulated "gather stats" which calls
ApplyToAllEntries at a specified interval. We also generate a histogram
of time to run ApplyToAllEntries.

To make the iteration over some entries of each shard work as cleanly as
possible, even with resize between next set of entries, I have
re-arranged which hash bits are used for sharding and which for indexing
within a shard.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8225

Test Plan:
A couple of unit tests are added, but primary validation is manual, as
the primary risk is to performance.

The primary validation is using cache_bench to ensure that neither
the minor hashing changes nor the simulated stats gathering
significantly impact QPS or latency distribution. Note that adding op
latency histogram seriously impacts the benchmark QPS, so for a
fair baseline, we need the cache_bench changes (except remove simulated
stat gathering to make it compile). In short, we don't see any
reproducible difference in ops/sec or op latency unless we are gathering
stats nearly continuously. Test uses 10GB block cache with
8KB values to be somewhat realistic in the number of items to iterate
over.

Baseline typical output:

```
Complete in 92.017 s; Rough parallel ops/sec = 869401
Thread ops/sec = 54662

Operation latency (ns):
Count: 80000000 Average: 11223.9494  StdDev: 29.61
Min: 0  Median: 7759.3973  Max: 9620500
Percentiles: P50: 7759.40 P75: 14190.73 P99: 46922.75 P99.9: 77509.84 P99.99: 217030.58
------------------------------------------------------
[       0,       1 ]       68   0.000%   0.000%
(    2900,    4400 ]       89   0.000%   0.000%
(    4400,    6600 ] 33630240  42.038%  42.038% ########
(    6600,    9900 ] 18129842  22.662%  64.700% #####
(    9900,   14000 ]  7877533   9.847%  74.547% ##
(   14000,   22000 ] 15193238  18.992%  93.539% ####
(   22000,   33000 ]  3037061   3.796%  97.335% #
(   33000,   50000 ]  1626316   2.033%  99.368%
(   50000,   75000 ]   421532   0.527%  99.895%
(   75000,  110000 ]    56910   0.071%  99.966%
(  110000,  170000 ]    16134   0.020%  99.986%
(  170000,  250000 ]     5166   0.006%  99.993%
(  250000,  380000 ]     3017   0.004%  99.996%
(  380000,  570000 ]     1337   0.002%  99.998%
(  570000,  860000 ]      805   0.001%  99.999%
(  860000, 1200000 ]      319   0.000% 100.000%
( 1200000, 1900000 ]      231   0.000% 100.000%
( 1900000, 2900000 ]      100   0.000% 100.000%
( 2900000, 4300000 ]       39   0.000% 100.000%
( 4300000, 6500000 ]       16   0.000% 100.000%
( 6500000, 9800000 ]        7   0.000% 100.000%
```

New, gather_stats=false. Median thread ops/sec of 5 runs:

```
Complete in 92.030 s; Rough parallel ops/sec = 869285
Thread ops/sec = 54458

Operation latency (ns):
Count: 80000000 Average: 11298.1027  StdDev: 42.18
Min: 0  Median: 7722.0822  Max: 6398720
Percentiles: P50: 7722.08 P75: 14294.68 P99: 47522.95 P99.9: 85292.16 P99.99: 228077.78
------------------------------------------------------
[       0,       1 ]      109   0.000%   0.000%
(    2900,    4400 ]      793   0.001%   0.001%
(    4400,    6600 ] 34054563  42.568%  42.569% #########
(    6600,    9900 ] 17482646  21.853%  64.423% ####
(    9900,   14000 ]  7908180   9.885%  74.308% ##
(   14000,   22000 ] 15032072  18.790%  93.098% ####
(   22000,   33000 ]  3237834   4.047%  97.145% #
(   33000,   50000 ]  1736882   2.171%  99.316%
(   50000,   75000 ]   446851   0.559%  99.875%
(   75000,  110000 ]    68251   0.085%  99.960%
(  110000,  170000 ]    18592   0.023%  99.983%
(  170000,  250000 ]     7200   0.009%  99.992%
(  250000,  380000 ]     3334   0.004%  99.997%
(  380000,  570000 ]     1393   0.002%  99.998%
(  570000,  860000 ]      700   0.001%  99.999%
(  860000, 1200000 ]      293   0.000% 100.000%
( 1200000, 1900000 ]      196   0.000% 100.000%
( 1900000, 2900000 ]       69   0.000% 100.000%
( 2900000, 4300000 ]       32   0.000% 100.000%
( 4300000, 6500000 ]       10   0.000% 100.000%
```

New, gather_stats=true, 1 second delay between scans. Scans take about
1 second here so it's spending about 50% time scanning. Still the effect on
ops/sec and latency seems to be in the noise. Median thread ops/sec of 5 runs:

```
Complete in 91.890 s; Rough parallel ops/sec = 870608
Thread ops/sec = 54551

Operation latency (ns):
Count: 80000000 Average: 11311.2629  StdDev: 45.28
Min: 0  Median: 7686.5458  Max: 10018340
Percentiles: P50: 7686.55 P75: 14481.95 P99: 47232.60 P99.9: 79230.18 P99.99: 232998.86
------------------------------------------------------
[       0,       1 ]       71   0.000%   0.000%
(    2900,    4400 ]      291   0.000%   0.000%
(    4400,    6600 ] 34492060  43.115%  43.116% #########
(    6600,    9900 ] 16727328  20.909%  64.025% ####
(    9900,   14000 ]  7845828   9.807%  73.832% ##
(   14000,   22000 ] 15510654  19.388%  93.220% ####
(   22000,   33000 ]  3216533   4.021%  97.241% #
(   33000,   50000 ]  1680859   2.101%  99.342%
(   50000,   75000 ]   439059   0.549%  99.891%
(   75000,  110000 ]    60540   0.076%  99.967%
(  110000,  170000 ]    14649   0.018%  99.985%
(  170000,  250000 ]     5242   0.007%  99.991%
(  250000,  380000 ]     3260   0.004%  99.995%
(  380000,  570000 ]     1599   0.002%  99.997%
(  570000,  860000 ]     1043   0.001%  99.999%
(  860000, 1200000 ]      471   0.001%  99.999%
( 1200000, 1900000 ]      275   0.000% 100.000%
( 1900000, 2900000 ]      143   0.000% 100.000%
( 2900000, 4300000 ]       60   0.000% 100.000%
( 4300000, 6500000 ]       27   0.000% 100.000%
( 6500000, 9800000 ]        7   0.000% 100.000%
( 9800000, 14000000 ]        1   0.000% 100.000%

Gather stats latency (us):
Count: 46 Average: 980387.5870  StdDev: 60911.18
Min: 879155  Median: 1033777.7778  Max: 1261431
Percentiles: P50: 1033777.78 P75: 1120666.67 P99: 1261431.00 P99.9: 1261431.00 P99.99: 1261431.00
------------------------------------------------------
(  860000, 1200000 ]       45  97.826%  97.826% ####################
( 1200000, 1900000 ]        1   2.174% 100.000%

Most recent cache entry stats:
Number of entries: 1295133
Total charge: 9.88 GB
Average key size: 23.4982
Average charge: 8.00 KB
Unique deleters: 3
```

Reviewed By: mrambacher

Differential Revision: D28295742

Pulled By: pdillinger

fbshipit-source-id: bbc4a552f91ba0fe10e5cc025c42cef5a81f2b95
2021-05-11 16:17:10 -07:00
mrambacher
9f2d255aed Add ObjectRegistry to ConfigOptions (#8166)
Summary:
This change enables a couple of things:
- Different ConfigOptions can have different registry/factory associated with it, thereby allowing things like a "Test" ConfigOptions versus a "Production"
- The ObjectRegistry is created fewer times and can be re-used

The ConfigOptions can also be initialized/constructed from a DBOptions, in which case it will grab some of its settings (Env, Logger) from the DBOptions.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8166

Reviewed By: zhichao-cao

Differential Revision: D27657952

Pulled By: mrambacher

fbshipit-source-id: ae1d6200bb7ab127405cdeefaba43c7fe694dfdd
2021-05-11 06:47:22 -07:00
mrambacher
ff463742b5 Add Merge Operator support to WriteBatchWithIndex (#8135)
Summary:
The WBWI has two differing modes of operation dependent on the value
of the constructor parameter `overwrite_key`.
Currently, regardless of the parameter, neither mode performs as
expected when using Merge. This PR remedies this by correctly invoking
the appropriate Merge Operator before returning results from the WBWI.

Examples of issues that exist which are solved by this PR:

## Example 1 with `overwrite_key=false`
Currently, from an empty database, the following sequence:
```
Put('k1', 'v1')
Merge('k1', 'v2')
Get('k1')
```
Incorrectly yields `v2`, that is to say that the Merge behaves like a Put.

## Example 2 with o`verwrite_key=true`
Currently, from an empty database, the following sequence:
```
Put('k1', 'v1')
Merge('k1', 'v2')
Get('k1')
```
Incorrectly yields `ERROR: kMergeInProgress`.

## Example 3 with `overwrite_key=false`
Currently, with a database containing `('k1' -> 'v1')`, the following sequence:
```
Merge('k1', 'v2')
GetFromBatchAndDB('k1')
```
Incorrectly yields `v1,v2`

## Example 4 with `overwrite_key=true`
Currently, with a database containing `('k1' -> 'v1')`, the following sequence:
```
Merge('k1', 'v1')
GetFromBatchAndDB('k1')
```
Incorrectly yields `ERROR: kMergeInProgress`.

## Example 5 with `overwrite_key=false`
Currently, from an empty database, the following sequence:
```
Put('k1', 'v1')
Merge('k1', 'v2')
GetFromBatchAndDB('k1')
```
Incorrectly yields `v1,v2`

## Example 6 with `overwrite_key=true`
Currently, from an empty database, `('k1' -> 'v1')`, the following sequence:
```
Put('k1', 'v1')
Merge('k1', 'v2')
GetFromBatchAndDB('k1')
```
Incorrectly yields `ERROR: kMergeInProgress`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8135

Reviewed By: pdillinger

Differential Revision: D27657938

Pulled By: mrambacher

fbshipit-source-id: 0fbda6bbc66bedeba96a84786d90141d776297df
2021-05-10 12:50:25 -07:00
sdong
f89a53655d Change date format in HISTORY.md (#8278)
Summary:
Per previous discussion, change date format in HISTORY.md to follow ISO 8601.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8278

Reviewed By: jay-zhuang

Differential Revision: D28294022

fbshipit-source-id: 563f29c56143519b4a871df82a17dd0a168a578c
2021-05-07 16:16:30 -07:00
Andrew Kryczka
a639c02f8e Allow applying CompactionFilter outside of compaction (#8243)
Summary:
From HISTORY.md release note:

- Allow `CompactionFilter`s to apply in more table file creation scenarios such as flush and recovery. For compatibility, `CompactionFilter`s by default apply during compaction. Users can customize this behavior by overriding `CompactionFilterFactory::ShouldFilterTableFileCreation()`.
- Removed unused structure `CompactionFilterContext`

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8243

Test Plan: added unit tests

Reviewed By: pdillinger

Differential Revision: D28088089

Pulled By: ajkr

fbshipit-source-id: 0799be7908e3b39fea09fc3f1ab00e13ad817fae
2021-05-07 16:01:40 -07:00
Peter Dillinger
c26b75baa5 Deprecate obsolete "backupable db" from public APIs (#8274)
Summary:
An early design of BackupEngine used stackable DB, so I guess a
DB had to opt-in to being backupable. Unfortunately the naming of that
obsolete design still infects our public API and implementation.

This change fixes the public API, with a deprecated
backward-compatibility header. `BackupableDBOptions` is renamed to
`BackupEngineOptions` (copy-replace in the public header) and
backup_engine.h replaces backupable_db.h (present for backward
compatibility). The only other change in backupable_db.h ->
backup_engine.h is cleaning up headers.

Later changes will fix the internal implementation.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8274

Test Plan:
The internal implementation of BackupEngine uses the name
BackupEngineOptions, while the unit tests use the old name
BackupableDBOptions. This gives me confidence that both still work.

Reviewed By: mrambacher

Differential Revision: D28259471

Pulled By: pdillinger

fbshipit-source-id: a25dbe327b9772143488e7bb0ec7139ee42d0613
2021-05-07 13:53:15 -07:00
sdong
a4919d6b62 Cap automatic arena block size to 1 MB (#7907)
Summary:
Larger arena block size does provide the benefit of reducing allocation overhead, however it may cause other troubles. For example, allocator is more likely not to allocate them to physical memory and trigger page fault. Weighing the risk, we cap the arena block size to 1MB. Users can always use a larger value if they want.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7907

Test Plan: Run all existing tests

Reviewed By: pdillinger

Differential Revision: D26135269

fbshipit-source-id: b7f55afd03e6ee1d8715f90fa11b6c33944e9ea8
2021-05-07 13:15:34 -07:00
Andrew Kryczka
0f42e50fec Fix GetLiveFiles() returning OPTIONS-000000 (#8268)
Summary:
See release note in HISTORY.md.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8268

Test Plan: unit test repro

Reviewed By: siying

Differential Revision: D28227901

Pulled By: ajkr

fbshipit-source-id: faf61d13b9e43a761e3d5dcf8203923126b51339
2021-05-05 12:54:46 -07:00
Peter Dillinger
3b981eaa1d Fix use-after-free threading bug in ClockCache (#8261)
Summary:
In testing for https://github.com/facebook/rocksdb/issues/8225 I found cache_bench would crash with
-use_clock_cache, as well as db_bench -use_clock_cache, but not
single-threaded. Smaller cache size hits failure much faster. ASAN
reported the failuer as calling malloc_usable_size on the `key` pointer
of a ClockCache handle after it was reportedly freed. On detailed
inspection I found this bad sequence of operations for a cache entry:

state=InCache=1,refs=1
[thread 1] Start ClockCacheShard::Unref (from Release, no mutex)
[thread 1] Decrement ref count
state=InCache=1,refs=0
[thread 1] Suspend before CalcTotalCharge (no mutex)

[thread 2] Start UnsetInCache (from Insert, mutex held)
[thread 2] clear InCache bit
state=InCache=0,refs=0
[thread 2] Calls RecycleHandle (based on pre-updated state)
[thread 2] Returns to Insert which calls Cleanup which deletes `key`

[thread 1] Resume ClockCacheShard::Unref
[thread 1] Read `key` in CalcTotalCharge

To fix this, I've added a field to the handle to store the metadata
charge so that we can efficiently remember everything we need from
the handle in Unref. We must not read from the handle again if we
decrement the count to zero with InCache=1, which means we don't own
the entry and someone else could eject/overwrite it immediately.

Note before this change, on amd64 sizeof(Handle) == 56 even though there
are only 48 bytes of data. Grouping together the uint32_t fields would
cut it down to 48, but I've added another uint32_t, which takes it
back up to 56. Not a big deal.

Also fixed DisownData to cooperate with ASAN as in LRUCache.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8261

Test Plan:
Manual + adding use_clock_cache to db_crashtest.py

Base performance
./cache_bench -use_clock_cache
Complete in 17.060 s; QPS = 2458513
New performance
./cache_bench -use_clock_cache
Complete in 17.052 s; QPS = 2459695

Any difference is easily buried in small noise.

Crash test shows still more bug(s) in ClockCache, so I'm expecting to
disable ClockCache from production code in a follow-up PR (if we
can't find and fix the bug(s))

Reviewed By: mrambacher

Differential Revision: D28207358

Pulled By: pdillinger

fbshipit-source-id: aa7a9322afc6f18f30e462c75dbbe4a1206eb294
2021-05-04 22:18:00 -07:00
Peter Dillinger
d2ca04e3ed Add more LSM info to FilterBuildingContext (#8246)
Summary:
Add `num_levels`, `is_bottommost`, and table file creation
`reason` to `FilterBuildingContext`, in anticipation of more powerful
Bloom-like filter support.

To support this, added `is_bottommost` and `reason` to
`TableBuilderOptions`, which allowed removing `reason` parameter from
`rocksdb::BuildTable`.

I attempted to remove `skip_filters` from `TableBuilderOptions`, because
filter construction decisions should arise from options, not one-off
parameters. I could not completely remove it because the public API for
SstFileWriter takes a `skip_filters` parameter, and translating this
into an option change would mean awkwardly replacing the table_factory
if it is BlockBasedTableFactory with new filter_policy=nullptr option.
I marked this public skip_filters option as deprecated because of this
oddity. (skip_filters on the read side probably makes sense.)

At least `skip_filters` is now largely hidden for users of
`TableBuilderOptions` and is no longer used for implementing the
optimize_filters_for_hits option. Bringing the logic for that option
closer to handling of FilterBuildingContext makes it more obvious that
hese two are using the same notion of "bottommost." (Planned:
configuration options for Bloom-like filters that generalize
`optimize_filters_for_hits`)

Recommended follow-up: Try to get away from "bottommost level" naming of
things, which is inaccurate (see
VersionStorageInfo::RangeMightExistAfterSortedRun), and move to
"bottommost run" or just "bottommost."

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8246

Test Plan:
extended an existing unit test to exercise and check various
filter building contexts. Also, existing tests for
optimize_filters_for_hits validate some of the "bottommost" handling,
which is now closely connected to FilterBuildingContext::is_bottommost
through TableBuilderOptions::is_bottommost

Reviewed By: mrambacher

Differential Revision: D28099346

Pulled By: pdillinger

fbshipit-source-id: 2c1072e29c24d4ac404c761a7b7663292372600a
2021-04-30 13:50:13 -07:00
Peter Dillinger
85becd94c1 Refactor: use TableBuilderOptions to reduce parameter lists (#8240)
Summary:
Greatly reduced the not-quite-copy-paste giant parameter lists
of rocksdb::NewTableBuilder, rocksdb::BuildTable,
BlockBasedTableBuilder::Rep ctor, and BlockBasedTableBuilder ctor.

Moved weird separate parameter `uint32_t column_family_id` of
TableFactory::NewTableBuilder into TableBuilderOptions.

Re-ordered parameters to TableBuilderOptions ctor, so that `uint64_t
target_file_size` is not randomly placed between uint64_t timestamps
(was easy to mix up).

Replaced a couple of fields of BlockBasedTableBuilder::Rep with a
FilterBuildingContext. The motivation for this change is making it
easier to pass along more data into new fields in FilterBuildingContext
(follow-up PR).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8240

Test Plan: ASAN make check

Reviewed By: mrambacher

Differential Revision: D28075891

Pulled By: pdillinger

fbshipit-source-id: fddb3dbb8260a0e8bdcbb51b877ebabf9a690d4f
2021-04-29 07:00:50 -07:00
Akanksha Mahajan
a0e0feca62 Improve BlockPrefetcher to prefetch only for sequential scans (#7394)
Summary:
BlockPrefetcher is used by iterators to prefetch data if they
anticipate more data to be used in future and this is valid for forward sequential
scans. But BlockPrefetcher tracks only num_file_reads_ and not if reads
are sequential. This presents problem for MultiGet with large number of
keys when it reseeks index iterator and data block. FilePrefetchBuffer
can end up doing large readahead for reseeks as readahead size
increases exponentially once readahead is enabled. Same issue is with
BlockBasedTableIterator.

Add previous length and offset read as well in BlockPrefetcher (creates
FilePrefetchBuffer) and FilePrefetchBuffer (does prefetching of data) to
determine if reads are sequential and then  prefetch.

Update the last block read after cache hit to take reads from cache also
in account.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7394

Test Plan: Add new unit test case

Reviewed By: anand1976

Differential Revision: D23737617

Pulled By: akankshamahajan15

fbshipit-source-id: 8e6917c25ed87b285ee495d1b68dc623d71205a3
2021-04-28 12:53:46 -07:00
Zhichao Cao
09a9ec3ac0 Fix the false positive alert of CF consistency check in WAL recovery (#8207)
Summary:
In current RocksDB, in recover the information form WAL, we do the consistency check for each column family when one WAL file is corrupted and PointInTimeRecovery is set. However, it will report a false positive alert on "SST file is ahead of WALs" when one of the CF current log number is greater than the corrupted WAL number (CF contains the data beyond the corrupted WAl) due to a new column family creation during flush. In this case, a new WAL is created (it is empty) during a flush. Also, due to some reason (e.g., storage issue or crash happens before SyncCloseLog is called), the old WAL is corrupted. The new CF has no data, therefore, it does not have the consistency issue.

Fix: when checking cfd->GetLogNumber() > corrupted_wal_number also check cfd->GetLiveSstFilesSize() > 0. So the CFs with no SST file data will skip the check here.

Note potential ignored inconsistency caused due to fix: empty CF can also be caused by write+delete. In this case, after flush, there is no SST files being generated. However, this CF still have the log in the WAL. When the WAL is corrupted, the DB might be inconsistent.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8207

Test Plan: added unit test, make crash_test

Reviewed By: riversand963

Differential Revision: D27898839

Pulled By: zhichao-cao

fbshipit-source-id: 931fc2d8b92dd00b4169bf84b94e712fd688a83e
2021-04-22 10:28:37 -07:00
Akanksha Mahajan
596e9008e4 Stall writes in WriteBufferManager when memory_usage exceeds buffer_size (#7898)
Summary:
When WriteBufferManager is shared across DBs and column families
to maintain memory usage under a limit, OOMs have been observed when flush cannot
finish but writes continuously insert to memtables.
In order to avoid OOMs, when memory usage goes beyond buffer_limit_ and DBs tries to write,
this change will stall incoming writers until flush is completed and memory_usage
drops.

Design: Stall condition: When total memory usage exceeds WriteBufferManager::buffer_size_
(memory_usage() >= buffer_size_) WriterBufferManager::ShouldStall() returns true.

DBImpl first block incoming/future writers by calling write_thread_.BeginWriteStall()
(which adds dummy stall object to the writer's queue).
Then DB is blocked on a state State::Blocked (current write doesn't go
through). WBStallInterface object maintained by every DB instance is added to the queue of
WriteBufferManager.

If multiple DBs tries to write during this stall, they will also be
blocked when check WriteBufferManager::ShouldStall() returns true.

End Stall condition: When flush is finished and memory usage goes down, stall will end only if memory
waiting to be flushed is less than buffer_size/2. This lower limit will give time for flush
to complete and avoid continous stalling if memory usage remains close to buffer_size.

WriterBufferManager::EndWriteStall() is called,
which removes all instances from its queue and signal them to continue.
Their state is changed to State::Running and they are unblocked. DBImpl
then signal all incoming writers of that DB to continue by calling
write_thread_.EndWriteStall() (which removes dummy stall object from the
queue).

DB instance creates WBMStallInterface which is an interface to block and
signal DBs during stall.
When DB needs to be blocked or signalled by WriteBufferManager,
state_for_wbm_ state is changed accordingly (RUNNING or BLOCKED).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7898

Test Plan: Added a new test db/db_write_buffer_manager_test.cc

Reviewed By: anand1976

Differential Revision: D26093227

Pulled By: akankshamahajan15

fbshipit-source-id: 2bbd982a3fb7033f6de6153aa92a221249861aae
2021-04-21 13:54:02 -07:00
Peter Dillinger
95f6add746 Revert Ribbon starting level support from #8198 (#8212)
Summary:
This partially reverts commit 10196d7edc.

The problem with this change is because of important filter use cases:
FIFO compaction and SST writer. FIFO "compaction" always uses level 0 so
would only use Ribbon filters if specifically including level 0 for the
Ribbon filter policy. SST writer sets level_at_creation=-1 to indicate
unknown level, and this would be treated the same as level 0 unless
fixed.

We are keeping the part about committing to permanent schema, which is
only changes to API comments and HISTORY.md.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8212

Test Plan: CI

Reviewed By: jay-zhuang

Differential Revision: D27896468

Pulled By: pdillinger

fbshipit-source-id: 50a775f7cba5d64fb729d9b982e355864020596e
2021-04-20 19:46:40 -07:00
Andrew Kryczka
905dd17b35 Fix seqno in ingested file boundary key metadata (#8209)
Summary:
Fixes https://github.com/facebook/rocksdb/issues/6245.

Adapted from https://github.com/facebook/rocksdb/issues/8201 and https://github.com/facebook/rocksdb/issues/8205.

Previously we were writing the ingested file's smallest/largest internal keys
with sequence number zero, or `kMaxSequenceNumber` in case of range
tombstone. The former (sequence number zero) is incorrect and can lead
to files being incorrectly ordered. The fix in this PR is to overwrite
boundary keys that have sequence number zero with the ingested file's assigned
sequence number.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8209

Test Plan: repro unit test

Reviewed By: riversand963

Differential Revision: D27885678

Pulled By: ajkr

fbshipit-source-id: 4a9f2c6efdfff81c3a9923e915ea88b250ee7b6a
2021-04-20 14:00:21 -07:00