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57 commits

Author SHA1 Message Date
Peter Dillinger 7a1b0207e6 format_version=6 and context-aware block checksums (#9058)
Summary:
## Context checksum
All RocksDB checksums currently use 32 bits of checking
power, which should be 1 in 4 billion false negative (FN) probability (failing to
detect corruption). This is true for random corruptions, and in some cases
small corruptions are guaranteed to be detected. But some possible
corruptions, such as in storage metadata rather than storage payload data,
would have a much higher FN rate. For example:
* Data larger than one SST block is replaced by data from elsewhere in
the same or another SST file. Especially with block_align=true, the
probability of exact block size match is probably around 1 in 100, making
the FN probability around that same. Without `block_align=true` the
probability of same block start location is probably around 1 in 10,000,
for FN probability around 1 in a million.

To solve this problem in new format_version=6, we add "context awareness"
to block checksum checks. The stored and expected checksum value is
modified based on the block's position in the file and which file it is in. The
modifications are cleverly chosen so that, for example
* blocks within about 4GB of each other are guaranteed to use different context
* blocks that are offset by exactly some multiple of 4GiB are guaranteed to use
different context
* files generated by the same process are guaranteed to use different context
for the same offsets, until wrap-around after 2^32 - 1 files

Thus, with format_version=6, if a valid SST block and checksum is misplaced,
its checksum FN probability should be essentially ideal, 1 in 4B.

## Footer checksum
This change also adds checksum protection to the SST footer (with
format_version=6), for the first time without relying on whole file checksum.
To prevent a corruption of the format_version in the footer (e.g. 6 -> 5) to
defeat the footer checksum, we change much of the footer data format
including an "extended magic number" in format_version 6 that would be
interpreted as empty index and metaindex block handles in older footer
versions. We also change the encoding of handles to free up space for
other new data in footer.

## More detail: making space in footer
In order to keep footer the same size in format_version=6 (avoid change to IO
patterns), we have to free up some space for new data. We do this two ways:
* Metaindex block handle is encoded down to 4 bytes (from 10) by assuming
it immediately precedes the footer, and by assuming it is < 4GB.
* Index block handle is moved into metaindex. (I don't know why it was
in footer to begin with.)

## Performance
In case of small performance penalty, I've made a "pay as you go" optimization
to compensate: replace `MutableCFOptions` in BlockBasedTableBuilder::Rep
with the only field used in that structure after construction: `prefix_extractor`.
This makes the PR an overall performance improvement (results below).

Nevertheless I'm seeing essentially no difference going from fv=5 to fv=6,
even including that improvement for both. That's based on extreme case table
write performance testing, many files with many blocks. This is relatively
checksum intensive (small blocks) and salt generation intensive (small files).

```
(for I in `seq 1 100`; do TEST_TMPDIR=/dev/shm/dbbench2 ./db_bench -benchmarks=fillseq -memtablerep=vector -disable_wal=1 -allow_concurrent_memtable_write=false -num=3000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -write_buffer_size=100000 -compression_type=none -block_size=1000; done) 2>&1 | grep micros/op | tee out
awk '{ tot += $5; n += 1; } END { print int(1.0 * tot / n) }' < out
```

Each value below is ops/s averaged over 100 runs, run simultaneously with competing
configuration for load fairness

Before -> after (both fv=5): 483530 -> 483673 (negligible)
Re-run 1: 480733 -> 485427 (1.0% faster)
Re-run 2: 483821 -> 484541 (0.1% faster)
Before (fv=5) -> after (fv=6): 482006 -> 485100 (0.6% faster)
Re-run 1: 482212 -> 485075 (0.6% faster)
Re-run 2: 483590 -> 484073 (0.1% faster)
After fv=5 -> after fv=6: 483878 -> 485542 (0.3% faster)
Re-run 1: 485331 -> 483385 (0.4% slower)
Re-run 2: 485283 -> 483435 (0.4% slower)
Re-run 3: 483647 -> 486109 (0.5% faster)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9058

Test Plan:
unit tests included (table_test, db_properties_test, salt in env_test). General DB tests
and crash test updated to test new format_version.

Also temporarily updated the default format version to 6 and saw some test failures. Almost all
were due to an inadvertent additional read in VerifyChecksum to verify the index block checksum,
though it's arguably a bug that VerifyChecksum does not appear to (re-)verify the index block
checksum, just assuming it was verified in opening the index reader (probably *usually* true but
probably not always true). Some other concerns about VerifyChecksum are left in FIXME
comments. The only remaining test failure on change of default (in block_fetcher_test) now
has a comment about how to upgrade the test.

The format compatibility test does not need updating because we have not updated the default
format_version.

Reviewed By: ajkr, mrambacher

Differential Revision: D33100915

Pulled By: pdillinger

fbshipit-source-id: 8679e3e572fa580181a737fd6d113ed53c5422ee
2023-07-30 16:40:01 -07:00
Yu Zhang 5dd8c114bb Add a UDT comparator for ReverseBytewiseComparator to object library (#11647)
Summary:
Add a built-in comparator that supports uint64_t style user-defined timestamps for ReverseBytewiseComparator.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11647

Test Plan:
Added a test wrapper for retrieving this comparator from registry and used it in this test:
`./udt_util_test`

Reviewed By: ltamasi

Differential Revision: D47848303

Pulled By: jowlyzhang

fbshipit-source-id: 5af5534a8c2d9195997d0308c8e194c1c797548c
2023-07-27 15:31:22 -07:00
Yu Zhang d1ae7f6c41 Add support to strip / pad timestamp when writing / reading a block (#11472)
Summary:
This patch adds support in `BlockBuilder` to strip user-defined timestamp from the `key` added via `Add(key, value)` and its equivalent APIs. The stripping logic is different when the key is either a user key or an internal key, so the `BlockBuilder` is created with a flag to indicate that. This patch also add support on the read path to APIs `NewIndexIterator`, `NewDataIterator` to support pad a min timestamp.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11472

Test Plan:
Three test modes are added to parameterize existing tests:
UserDefinedTimestampTestMode::kNone -> UDT feature is not enabled
UserDefinedTimestampTestMode::kNormal -> UDT feature enabled, write / read with min timestamp
UserDefinedTimestampTestMode::kStripUserDefinedTimestamps -> UDT feature enabled, write / read with min timestamp, set `persist_user_defined_timestamps` where it applies to false.
The tests read/write with min timestamp so that point read and range scan can correctly read values in all three test modes.

`block_test` are parameterized to run with above three test modes and some additional parameteriazation

```
make all check
./block_test --gtest_filter="P/BlockTest*"
./block_test --gtest_filter="P/IndexBlockTest*"
```

Reviewed By: ltamasi

Differential Revision: D46200539

Pulled By: jowlyzhang

fbshipit-source-id: 59f5d6b584639976b69c2943eba723bd47d9b3c0
2023-05-25 15:41:32 -07:00
Peter Dillinger fb63d9b4ee Fix compression tests when snappy not available (#11396)
Summary:
Tweak some bounds and things, and reduce risk of surprise results by running on all supported compressions (mostly).

Also improves the precise compressibility of CompressibleString by using RandomBinaryString.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11396

Test Plan: updated tests

Reviewed By: ltamasi

Differential Revision: D45211938

Pulled By: pdillinger

fbshipit-source-id: 9dc1dd8574a60a9364efe18558be66d31a35598b
2023-04-22 12:41:36 -07:00
Changyu Bi ba16e8eee7 Try to pick more files in LevelCompactionBuilder::TryExtendNonL0TrivialMove() (#11347)
Summary:
Before this PR, in `LevelCompactionBuilder::TryExtendNonL0TrivialMove(index)`, we start from a file at index and expand the compaction input towards right to find files to trivial move. This PR adds the logic to also expand towards left.

Another major change made in this PR is to not expand L0 files through `TryExtendNonL0TrivialMove()`. This happens currently when compacting L0 files to an empty output level. The condition for expanding files in `TryExtendNonL0TrivialMove()` is to check atomic boundary, which does not take into account that L0 files can overlap in key range and are not sorted in key order. So it may include more L0 files than needed and disallow a trivial move. This change is included in this PR so that we don't make it worse by always expanding L0 in both direction.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11347

Test Plan:
* new unit test
* Benchmark does not show obvious improvement or regression:
```
Write sequentially
./db_bench --benchmarks=fillseq --compression_type=lz4 --write_buffer_size=1000000 --num=100000000 --value_size=100 -level_compaction_dynamic_level_bytes --target_file_size_base=7340032 --max_bytes_for_level_base=16777216

Main:
fillseq      :       4.726 micros/op 211592 ops/sec 472.607 seconds 100000000 operations;   23.4 MB/s
This PR:
fillseq      :       4.755 micros/op 210289 ops/sec 475.534 seconds 100000000 operations;   23.3 MB/s

Write randomly
./db_bench --benchmarks=fillrandom --compression_type=lz4 --write_buffer_size=1000000 --num=100000000 --value_size=100 -level_compaction_dynamic_level_bytes --target_file_size_base=7340032 --max_bytes_for_level_base=16777216

Main:
fillrandom   :      16.351 micros/op 61159 ops/sec 1635.066 seconds 100000000 operations;    6.8 MB/s
This PR:
fillrandom   :      15.798 micros/op 63298 ops/sec 1579.817 seconds 100000000 operations;    7.0 MB/s
```

Reviewed By: ajkr

Differential Revision: D44645650

Pulled By: cbi42

fbshipit-source-id: 8631f3a6b3f01decbbf18c34f2b62833cb4f9733
2023-04-14 11:50:20 -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
Yanqin Jin f648915b0d Fix a bug of not setting enforce_single_del_contracts (#10027)
Summary:
Before this PR, BuildDBOptions() does not set a newly-added option, i.e.
enforce_single_del_contracts, causing OPTIONS files to contain incorrect
information.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10027

Test Plan:
make check
Manually check OPTIONS file.

Reviewed By: ltamasi

Differential Revision: D36556125

Pulled By: riversand963

fbshipit-source-id: e1074715b22c328b68c19e9ad89aa5d67d864bb5
2022-05-20 16:48:50 -07:00
Jay Zhuang c6d326d3d7 Track SST unique id in MANIFEST and verify (#9990)
Summary:
Start tracking SST unique id in MANIFEST, which is used to verify with
SST properties to make sure the SST file is not overwritten or
misplaced. A DB option `try_verify_sst_unique_id` is introduced to
enable/disable the verification, if enabled, it opens all SST files
during DB-open to read the unique_id from table properties (default is
false), so it's recommended to use it with `max_open_files = -1` to
pre-open the files.

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

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

Reviewed By: anand1976

Differential Revision: D36381863

Pulled By: jay-zhuang

fbshipit-source-id: 89ea2eb6b35ed3e80ead9c724eb096083eaba63f
2022-05-19 11:04:21 -07:00
sdong 736a7b5433 Remove own ToString() (#9955)
Summary:
ToString() is created as some platform doesn't support std::to_string(). However, we've already used std::to_string() by mistake for 16 months (in db/db_info_dumper.cc). This commit just remove ToString().

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9955

Test Plan: Watch CI tests

Reviewed By: riversand963

Differential Revision: D36176799

fbshipit-source-id: bdb6dcd0e3a3ab96a1ac810f5d0188f684064471
2022-05-06 13:03:58 -07:00
sdong 33742c2a9f Remove BlockBasedTableOptions.hash_index_allow_collision (#9454)
Summary:
BlockBasedTableOptions.hash_index_allow_collision is already deprecated and has no effect. Delete it for preparing 7.0 release.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9454

Test Plan: Run all existing tests.

Reviewed By: ajkr

Differential Revision: D33805827

fbshipit-source-id: ed8a436d1d083173ec6aef2a762ba02e1eefdc9d
2022-03-01 13:58:02 -08:00
satyajanga 036bbab6f7 Use the comparator from the sst file table properties in sst_dump_tool (#9491)
Summary:
We introduced a new Comparator for timestamp in user keys. In the sst_dump_tool by default we use BytewiseComparator to read sst files. This change allows us to read comparator_name from table properties in meta data block and use it to read.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9491

Test Plan:
added unittests for new functionality.
make check
![image](https://user-images.githubusercontent.com/4923556/152915444-28b88a1f-7b4e-47d0-815f-7011552bd9a2.png)
![image](https://user-images.githubusercontent.com/4923556/152916196-bea3d2a1-a3d5-4362-b911-036131b83e8d.png)

Reviewed By: riversand963

Differential Revision: D33993614

Pulled By: satyajanga

fbshipit-source-id: 4b5cf938e6d2cb3931d763bef5baccc900b8c536
2022-02-08 12:15:35 -08:00
Baptiste Lemaire bec9ab4316 Remove deprecated option DBOptions::max_mem_compaction_level (#9446)
Summary:
In RocksDB, this option was already marked as "NOT SUPPORTED" for a long time, and setting this option does not have any effect on the behavior of RocksDB library. Therefore, we are removing it in the preparations of the upcoming 7.0 release.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9446

Reviewed By: ajkr

Differential Revision: D33793048

Pulled By: bjlemaire

fbshipit-source-id: 73316efdb194e90225005246673dae99e65577ae
2022-02-04 05:32:28 -08:00
Hui Xiao 42cca28ebb Remove deprecated API AdvancedColumnFamilyOptions::rate_limit_delay_max_milliseconds (#9455)
Summary:
**Context/Summary:**
AdvancedColumnFamilyOptions::rate_limit_delay_max_milliseconds has been marked as deprecated and it's time to actually remove the code.
- Keep `soft_rate_limit`/`hard_rate_limit` in `cf_mutable_options_type_info` to prevent throwing `InvalidArgument` in `GetColumnFamilyOptionsFromMap` when reading an option file still with these options (e.g, old option file generated from RocksDB before the deprecation)
- Keep `soft_rate_limit`/`hard_rate_limit` in under `OptionsOldApiTest.GetOptionsFromMapTest` to test the case mentioned above.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9455

Test Plan: Rely on my eyeball and CI

Reviewed By: ajkr

Differential Revision: D33811664

Pulled By: hx235

fbshipit-source-id: 866859427fe710354a90f1095057f80116365ff0
2022-01-28 16:47:08 -08:00
Akanksha Mahajan 74ccd1931e Remove deprecated option DBOptions::skip_log_error_on_recovery (#9434)
Summary:
In  RocksDB DBOptions::skip_log_error_on_recovery is marked as
"NOT SUPPORTED" for a long time, and setting this option does not have
any effect on the behavior of RocksDB library. Therefore, we are removing it
in the upcoming 7.0 release.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9434

Test Plan: CircleCI

Reviewed By: ajkr

Differential Revision: D33763015

Pulled By: akankshamahajan15

fbshipit-source-id: 11f09643298da6c02d3dcdb090b996f4c3cfdd76
2022-01-28 01:46:04 -08:00
Hui Xiao 1e0e883ca5 Remove deprecated API AdvancedColumnFamilyOptions::soft_rate_limit/hard_rate_limit (#9452)
Summary:
**Context/Summary:**
AdvancedColumnFamilyOptions::soft_rate_limit/hard_rate_limit have been marked as deprecated and it's time to actually remove the code.
- Keep `soft_rate_limit`/`hard_rate_limit` in `cf_mutable_options_type_info` to prevent throwing `InvalidArgument` in `GetColumnFamilyOptionsFromMap` when reading an option file still with these options (e.g, old option file generated from RocksDB before the deprecation)
- Keep `soft_rate_limit`/`hard_rate_limit` in under `OptionsOldApiTest.GetOptionsFromMapTest` to test the case mentioned above.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9452

Test Plan: Rely on my eyeball and CI

Reviewed By: ajkr

Differential Revision: D33804938

Pulled By: hx235

fbshipit-source-id: 133d49f7ec5238d7efceeb0a3122a5792a2b9945
2022-01-27 13:01:09 -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
mrambacher 1973fcba11 Restore Regex support for ObjectLibrary::Register, rename new APIs to allow old one to be deprecated in the future (#9362)
Summary:
In order to support old-style regex function registration, restored the original "Register<T>(string, Factory)" method using regular expressions.  The PatternEntry methods were left in place but renamed to AddFactory.  The goal is to allow for the deprecation of the original regex Registry method in an upcoming release.

Added modes to the PatternEntry kMatchZeroOrMore and kMatchAtLeastOne to match * or +, respectively (kMatchAtLeastOne was the original behavior).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9362

Reviewed By: pdillinger

Differential Revision: D33432562

Pulled By: mrambacher

fbshipit-source-id: ed88ab3f9a2ad0d525c7bd1692873f9bb3209d02
2022-01-11 06:33:48 -08:00
mrambacher 1c39b7952b Remove/Reduce use of Regex in ObjectRegistry/Library (#9264)
Summary:
Added new ObjectLibrary::Entry classes to replace/reduce the use of Regex.  For simple factories that only do name matching, there are "StringEntry" and "AltStringEntry" classes.  For classes that use some semblance of regular expressions, there is a PatternEntry class that can match a name and prefixes.  There is also a class for Customizable::IndividualId format matches.

Added tests for the new derivative classes and got all unit tests to pass.

Resolves https://github.com/facebook/rocksdb/issues/9225.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9264

Reviewed By: pdillinger

Differential Revision: D33062001

Pulled By: mrambacher

fbshipit-source-id: c2d2143bd2d38bdf522705c8280c35381b135c03
2021-12-29 07:56:23 -08:00
Peter Dillinger 653c392e47 More refactoring ahead of footer & meta changes (#9240)
Summary:
I'm working on a new format_version=6 to support context
checksum (https://github.com/facebook/rocksdb/issues/9058) and this includes much of the refactoring and test
updates to support that change.

Test coverage data and manual inspection agree on dead code in
block_based_table_reader.cc (removed).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9240

Test Plan:
tests enhanced to cover more cases etc.

Extreme case performance testing indicates small % regression in fillseq (w/ compaction), though CPU profile etc. doesn't suggest any explanation. There is enhanced correctness checking in Footer::DecodeFrom, but this should be negligible.

TEST_TMPDIR=/dev/shm/ ./db_bench -benchmarks=fillseq -memtablerep=vector -allow_concurrent_memtable_write=false -num=30000000 -checksum_type=1 --disable_wal={false,true}

(Each is ops/s averaged over 50 runs, run simultaneously with competing configuration for load fairness)
Before w/ wal: 454512
After w/ wal: 444820 (-2.1%)
Before w/o wal: 1004560
After w/o wal: 998897 (-0.6%)

Since this doesn't modify WAL code, one would expect real effects to be larger in w/o wal case.

This regression will be corrected in a follow-up PR.

Reviewed By: ajkr

Differential Revision: D32813769

Pulled By: pdillinger

fbshipit-source-id: 444a244eabf3825cd329b7d1b150cddce320862f
2021-12-10 08:13:26 -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
anand76 dddb791c18 Enable a few unit tests to use custom Env objects (#9087)
Summary:
Allow compaction_job_test, db_io_failure_test, dbformat_test, deletefile_test, and fault_injection_test to use a custom Env object. Also move ```RegisterCustomObjects``` declaration to a header file to simplify things.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9087

Test Plan: Run manually using "buck test rocksdb/src:compaction_job_test_fbcode" etc.

Reviewed By: riversand963

Differential Revision: D32007222

Pulled By: anand1976

fbshipit-source-id: 99af58559e25bf61563dfa95dc46e31fa7375792
2021-11-08 11:05:59 -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 6924869867 Make SystemClock into a Customizable Class (#8636)
Summary:
Made SystemClock into a Customizable class, complete with CreateFromString.

Cleaned up some of the existing SystemClock implementations that were redundant (NoSleep was the same as the internal one for MockEnv).

Changed MockEnv construction to allow Clock to be passed to the Memory/MockFileSystem.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8636

Reviewed By: zhichao-cao

Differential Revision: D30483360

Pulled By: mrambacher

fbshipit-source-id: cd0e3a876c39f8c98fe13374c06e8edbd5b9f2a1
2021-09-21 09:23:48 -07:00
mrambacher beed86473a Make MemTableRepFactory into a Customizable class (#8419)
Summary:
This PR does the following:
-> Makes the MemTableRepFactory into a Customizable class and creatable/configurable via CreateFromString
-> Makes the existing implementations compatible with configurations
-> Moves the "SpecialRepFactory" test class into testutil, accessible via the ObjectRegistry or a NewSpecial API

New tests were added to validate the functionality and all existing tests pass.  db_bench and memtablerep_bench were hand-tested to verify the functionality in those tools.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8419

Reviewed By: zhichao-cao

Differential Revision: D29558961

Pulled By: mrambacher

fbshipit-source-id: 81b7229636e4e649a0c914e73ac7b0f8454c931c
2021-09-08 07:46:44 -07:00
mrambacher 9eb002fcf0 Fix some minor issues in the Customizable infrastructure (#8566)
Summary:
- Fix issue with OptionType::Vector when the nested item is a Customizable with no names
- Fix issue with OptionType::Vector to appropriately wrap the elements in a Vector;
- Fix an issue with nested Customizable object with a null immutable object still appearing in the mutable options;
- Fix/Add tests for null/empty customizable objects
- Move the RegisterTestObjects from customizable_test into testutil.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8566

Reviewed By: zhichao-cao

Differential Revision: D30303724

Pulled By: mrambacher

fbshipit-source-id: 33fa8ea2a3b663210cb356da05e64aab7585b1b5
2021-08-19 10:10:47 -07:00
mrambacher 281ac9c89e Add CreateFrom methods to Env/FileSystem (#8174)
Summary:
- Added CreateFromString method to Env and FilesSystem to replace LoadEnv/Load.  This method/signature is a precursor to making these classes extend Customizable.

- Added CreateFromSystem to Env.  This method standardizes creating an Env from the environment variables.  Previously, some places would check TEST_ENV_URI and others would also check TEST_FS_URI.  Now the code is more command/standardized.

- Added CreateFromFlags to Env.  These method allows Env to be create from string options (such as GFLAGS options) in a more standard way.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/8174

Reviewed By: zhichao-cao

Differential Revision: D28999603

Pulled By: mrambacher

fbshipit-source-id: 88e6911e7e91f908458a7fe10a20e93ecbc275fb
2021-06-15 03:43:48 -07:00
mrambacher 12f1137355 Add a SystemClock class to capture the time functions of an Env (#7858)
Summary:
Introduces and uses a SystemClock class to RocksDB.  This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.

Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead.  There are likely more places that can be changed, but this is a start to show what can/should be done.  Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock.

There are several Env classes that implement these functions.  Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR.  It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc).

Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858

Reviewed By: pdillinger

Differential Revision: D26006406

Pulled By: mrambacher

fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
2021-01-25 22:09:11 -08:00
mrambacher e628f59e87 Create a CustomEnv class; Add WinFileSystem; Make LegacyFileSystemWrapper private (#7703)
Summary:
This PR does the following:
-> Creates a WinFileSystem class.  This class is the Windows equivalent of the PosixFileSystem and will be used on Windows systems.
-> Introduces a CustomEnv class.  A CustomEnv is an Env that takes a FileSystem as constructor argument.  I believe there will only ever be two implementations of this class (PosixEnv and WinEnv).  There is still a CustomEnvWrapper class that takes an Env and a FileSystem and wraps the Env calls with the input Env but uses the FileSystem for the FileSystem calls
-> Eliminates the public uses of the LegacyFileSystemWrapper.

With this change in place, there are effectively the following patterns of Env:
- "Base Env classes" (PosixEnv, WinEnv).  These classes implement the core Env functions (e.g. Threads) and have a hard-coded input FileSystem.  These classes inherit from CompositeEnv, implement the core Env functions (threads) and delegate the FileSystem-like calls to the input file system.
- Wrapped Composite Env classes (MemEnv).  These classes take in an Env and a FileSystem.  The core env functions are re-directed to the wrapped env.  The file system calls are redirected to the input file system
- Legacy Wrapped Env classes.  These classes take in an Env input (but no FileSystem).  The core env functions are re-directed to the wrapped env.  A "Legacy File System" is created using this env and the file system calls directed to the env itself.

With these changes in place, the PosixEnv becomes a singleton -- there is only ever one created.  Any other use of the PosixEnv is via another wrapped env.  This cleans up some of the issues with the env construction and destruction.

Additionally, there were places in the code that required had an Env when they required a FileSystem.  Many of these places would wrap the Env with a LegacyFileSystemWrapper instead of using the env->GetFileSystem().  These places were changed, thereby removing layers of additional redirection (LegacyFileSystem --> Env --> Env::FileSystem).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7703

Reviewed By: zhichao-cao

Differential Revision: D25762190

Pulled By: anand1976

fbshipit-source-id: 1a088e97fc916f28ac69c149cd1dcad0ab31704b
2021-01-06 10:49:32 -08:00
mrambacher c1a65a4de4 Make StringEnv, StringSink, StringSource use FS classes (#7786)
Summary:
Change the StringEnv and related classes to be based on FileSystem APIs rather than the corresponding Env ones.  The StringSink and StringSource classes were changed to be based on the corresponding FS file classes.

Part of a cleanup to use the newer interfaces.  This change also eliminates some of the casts/wrappers to LegacyFile classes.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7786

Reviewed By: jay-zhuang

Differential Revision: D25761460

Pulled By: anand1976

fbshipit-source-id: 428ae8e32b3db97dbeeca08c9d3bb0d9d4d3a38f
2021-01-04 16:01:01 -08:00
Adam Retter 8ff6557e7f Add further tests to ASSERT_STATUS_CHECKED (2) (#7698)
Summary:
Second batch of adding more tests to ASSERT_STATUS_CHECKED.

* external_sst_file_basic_test
* checkpoint_test
* db_wal_test
* db_block_cache_test
* db_logical_block_size_cache_test
* db_blob_index_test
* optimistic_transaction_test
* transaction_test
* point_lock_manager_test
* write_prepared_transaction_test
* write_unprepared_transaction_test

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7698

Reviewed By: cheng-chang

Differential Revision: D25441664

Pulled By: pdillinger

fbshipit-source-id: 9e78867f32321db5d4833e95eb96c5734526ef00
2020-12-09 21:21:16 -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
mrambacher f35f7f2704 Fix many tests to run with MEM_ENV and ENCRYPTED_ENV; Introduce a MemoryFileSystem class (#7566)
Summary:
This PR does a few things:

1.  The MockFileSystem class was split out from the MockEnv.  This change would theoretically allow a MockFileSystem to be used by other Environments as well (if we created a means of constructing one).  The MockFileSystem implements a FileSystem in its entirety and does not rely on any Wrapper implementation.

2.  Make the RocksDB test suite work when MOCK_ENV=1 and ENCRYPTED_ENV=1 are set.  To accomplish this, a few things were needed:
- The tests that tried to use the "wrong" environment (Env::Default() instead of env_) were updated
- The MockFileSystem was changed to support the features it was missing or mishandled (such as recursively deleting files in a directory or supporting renaming of a directory).

3.  Updated the test framework to have a ROCKSDB_GTEST_SKIP macro.  This can be used to flag tests that are skipped.  Currently, this defaults to doing nothing (marks the test as SUCCESS) but will mark the tests as SKIPPED when RocksDB is upgraded to a version of gtest that supports this (gtest-1.10).

I have run a full "make check" with MEM_ENV, ENCRYPTED_ENV,  both, and neither under both MacOS and RedHat.  A few tests were disabled/skipped for the MEM/ENCRYPTED cases.  The error_handler_fs_test fails/hangs for MEM_ENV (presumably a timing problem) and I will introduce another PR/issue to track that problem.  (I will also push a change to disable those tests soon).  There is one more test in DBTest2 that also fails which I need to investigate or skip before this PR is merged.

Theoretically, this PR should also allow the test suite to run against an Env loaded from the registry, though I do not have one to try it with currently.

Finally, once this is accepted, it would be nice if there was a CircleCI job to run these tests on a checkin so this effort does not become stale.  I do not know how to do that, so if someone could write that job, it would be appreciated :)

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7566

Reviewed By: zhichao-cao

Differential Revision: D24408980

Pulled By: jay-zhuang

fbshipit-source-id: 911b1554a4d0da06fd51feca0c090a4abdcb4a5f
2020-10-27 10:33:09 -07:00
Yanqin Jin 6595267980 Allow compaction iterator to perform garbage collection (#7556)
Summary:
Add a threshold timestamp, full_history_ts_low_ of type `std::string*` to
`CompactionIterator`, so that RocksDB can also perform garbage collection during
compaction.
* If full_history_ts_low_ is nullptr, then compaction iterator does not perform
  GC, preserving all timestamp history for all keys. Compaction iterator will
treat user key with different timestamps as different user keys.
* If full_history_ts_low_ is not nullptr, then compaction iterator performs
  GC. GC will look at keys older than `*full_history_ts_low_` and determine their
  eligibility based on factors including snapshots.

Current rules of GC:
 * If an internal key is in the same snapshot as a previous counterpart
    with the same user key, and this key is eligible for GC, and the key is
    not single-delete or merge operand, then this key can be dropped. Note
    that the previous internal key cannot be a merge operand either.
 * If a tombstone is the most recent one in the earliest snapshot and it
    is eligible for GC, and keyNotExistsBeyondLevel() is true, then this
    tombstone can be dropped.
 * If a tombstone is the most recent one in a snapshot and it is eligible
    for GC, and the compaction is at bottommost level, then all other older
    internal keys of the same user key must also be eligible for GC, thus
    can be dropped
* Single-delete, delete-range and merge are not currently supported.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7556

Test Plan: make check

Reviewed By: ltamasi

Differential Revision: D24507728

Pulled By: riversand963

fbshipit-source-id: 3c09c7301f41eed76dfcf4d1527e68cf6e0a8bb3
2020-10-23 22:59:46 -07:00
Cheng Chang 12b78e40bd Track WAL in MANIFEST: add option track_and_verify_wals_in_manifest (#7275)
Summary:
This option determines whether WALs will be tracked in MANIFEST and verified on recovery.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7275

Test Plan:
db_options_test
options_test

Reviewed By: pdillinger

Differential Revision: D23181418

Pulled By: cheng-chang

fbshipit-source-id: 5dd1cdc166f3dfc1c93c094df4a2f7734e3b4547
2020-10-09 16:42:19 -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
mrambacher c7c7b07f06 More Makefile Cleanup (#7097)
Summary:
Cleans up some of the dependencies on test code in the Makefile while building tools:
- Moves the test::RandomString, DBBaseTest::RandomString into Random
- Moves the test::RandomHumanReadableString into Random
- Moves the DestroyDir method into file_utils
- Moves the SetupSyncPointsToMockDirectIO into sync_point.
- Moves the FaultInjection Env and FS classes under env

These changes allow all of the tools to build without dependencies on test_util, thereby simplifying the build dependencies.  By moving the FaultInjection code, the dependency in db_stress on different libraries for debug vs release was eliminated.

Tested both release and debug builds via Make and CMake for both static and shared libraries.

More work remains to clean up how the tools are built and remove some unnecessary dependencies.  There is also more work that should be done to get the Makefile and CMake to align in their builds -- what is in the libraries and the sizes of the executables are different.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7097

Reviewed By: riversand963

Differential Revision: D22463160

Pulled By: pdillinger

fbshipit-source-id: e19462b53324ab3f0b7c72459dbc73165cc382b2
2020-07-09 14:35:17 -07:00
Peter Dillinger 90fd6b0cc8 cf_consistency_stress (crash_test_with_atomic_flush) checkpoint clean (#7103)
Summary:
Delicious copy-pasta from https://github.com/facebook/rocksdb/issues/7039

Also fixing DestroyDir to allow files to go missing while it is operating. This seems to fix failures I got with test plan reproducer.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7103

Test Plan:
make blackbox_crash_test_with_atomic_flush for a while with
checkpoint_one_in=100

Reviewed By: siying

Differential Revision: D22435315

Pulled By: pdillinger

fbshipit-source-id: 0ec0538402493887aeda43ecc03f32979cb84ced
2020-07-08 13:04:55 -07:00
anand76 98b0cbea88 Check iterator status BlockBasedTableReader::VerifyChecksumInBlocks() (#6909)
Summary:
The ```for``` loop in ```VerifyChecksumInBlocks``` only checks ```index_iter->Valid()``` which could be ```false``` either due to reaching the end of the index or, in case of partitioned index, it could be due to a checksum mismatch error when reading a 2nd level index block. Instead of throwing away the index iterator status, we need to return any errors back to the caller.

Tests:
Add a test in block_based_table_reader_test.cc.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6909

Reviewed By: pdillinger

Differential Revision: D21833922

Pulled By: anand1976

fbshipit-source-id: bc778ebf1121dbbdd768689de5183f07a9f0beae
2020-06-05 11:08:25 -07:00
Cheng Chang 1bee0fca05 Make DestroyDir destroy directories recursively (#6934)
Summary:
Currently, `DeleteDir` only deletes the directory if there are no other directories under the target dir. This PR makes it delete directories recursively.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6934

Test Plan:
Added a new unit test in testutil_test.cc.
`make testutil_test`

Reviewed By: zhichao-cao

Differential Revision: D21884211

Pulled By: cheng-chang

fbshipit-source-id: 0b9a48a200f494ee007aef5d1763b4aa331f8b5a
2020-06-05 10:55:22 -07:00
Cheng Chang 91b7553293 Enable IO Uring in MultiGet in direct IO mode (#6815)
Summary:
Currently, in direct IO mode, `MultiGet` retrieves the data blocks one by one instead of in parallel, see `BlockBasedTable::RetrieveMultipleBlocks`.

Since direct IO is supported in `RandomAccessFileReader::MultiRead` in https://github.com/facebook/rocksdb/pull/6446, this PR applies `MultiRead` to `MultiGet` so that the data blocks can be retrieved in parallel.

Also, in direct IO mode and when data blocks are compressed and need to uncompressed, this PR only allocates one continuous aligned buffer to hold the data blocks, and then directly uncompress the blocks to insert into block cache, there is no longer intermediate copies to scratch buffers.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6815

Test Plan:
1. added a new unit test `BlockBasedTableReaderTest::MultiGet`.
2. existing unit tests and stress tests  contain tests against `MultiGet` in direct IO mode.

Reviewed By: anand1976

Differential Revision: D21426347

Pulled By: cheng-chang

fbshipit-source-id: b8446ae0e74152444ef9111e97f8e402ac31b24f
2020-05-14 23:26:26 -07:00
Cheng Chang 0a77617820 Disable O_DIRECT in stress test when db directory does not support direct IO (#6727)
Summary:
In crash test, the db directory might be set to /dev/shm or /tmp, in certain environments such as internal testing infrastructure, neither of these directories support direct IO, so direct IO is never enabled in crash test.

This PR sets up SyncPoints in direct IO related code paths to disable O_DIRECT flag in calls to `open`, so the direct IO code paths will be executed, all direct IO related assertions will be checked, but no real direct IO request will be issued to the file system.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6727

Test Plan:
export CRASH_TEST_EXT_ARGS="--use_direct_reads=1 --mmap_read=0"
make -j24 crash_test

Reviewed By: zhichao-cao

Differential Revision: D21139250

Pulled By: cheng-chang

fbshipit-source-id: db9adfe78d91aa4759835b1af91c5db7b27b62ee
2020-04-25 00:01:03 -07:00
Cheng Chang 40497a875a Reduce memory copies when fetching and uncompressing blocks from SST files (#6689)
Summary:
In https://github.com/facebook/rocksdb/pull/6455, we modified the interface of `RandomAccessFileReader::Read` to be able to get rid of memcpy in direct IO mode.
This PR applies the new interface to `BlockFetcher` when reading blocks from SST files in direct IO mode.

Without this PR, in direct IO mode, when fetching and uncompressing compressed blocks, `BlockFetcher` will first copy the raw compressed block into `BlockFetcher::compressed_buf_` or `BlockFetcher::stack_buf_` inside `RandomAccessFileReader::Read` depending on the block size. then during uncompressing, it will copy the uncompressed block into `BlockFetcher::heap_buf_`.

In this PR, we get rid of the first memcpy and directly uncompress the block from `direct_io_buf_` to `heap_buf_`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6689

Test Plan: A new unit test `block_fetcher_test` is added.

Reviewed By: anand1976

Differential Revision: D21006729

Pulled By: cheng-chang

fbshipit-source-id: 2370b92c24075692423b81277415feb2aed5d980
2020-04-24 15:32:56 -07:00
Yanqin Jin eeb3cf3f58 Fix release build (#6690)
Summary:
Fix release build caused by variable defined but unused.

Test plan (devserver)
```
make release
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6690

Reviewed By: cheng-chang

Differential Revision: D20980571

Pulled By: riversand963

fbshipit-source-id: c3f3b13f81dce4bdb19876dc2e710d5902ff8a02
2020-04-11 22:04:04 -07:00
Yanqin Jin 0c05624d50 Compaction with timestamp: input boundaries (#6645)
Summary:
Towards making compaction logic compatible with user timestamp.
When computing boundaries and overlapping ranges for inputs of compaction, We need to compare SSTs by user key without timestamp.

Test plan (devserver):
```
make check
```
Several individual tests:
```
./version_set_test --gtest_filter=VersionStorageInfoTimestampTest.GetOverlappingInputs
./db_with_timestamp_compaction_test
./db_with_timestamp_basic_test
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6645

Reviewed By: ltamasi

Differential Revision: D20960012

Pulled By: riversand963

fbshipit-source-id: ad377fa9eb481bf7a8a3e1824aaade48cdc653a4
2020-04-10 16:05:49 -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
Mike Kolupaev 637e64b9ac Add an option to prevent DB::Open() from querying sizes of all sst files (#6353)
Summary:
When paranoid_checks is on, DBImpl::CheckConsistency() iterates over all sst files and calls Env::GetFileSize() for each of them. As far as I could understand, this is pretty arbitrary and doesn't affect correctness - if filesystem doesn't corrupt fsynced files, the file sizes will always match; if it does, it may as well corrupt contents as well as sizes, and rocksdb doesn't check contents on open.

If there are thousands of sst files, getting all their sizes takes a while. If, on top of that, Env is overridden to use some remote storage instead of local filesystem, it can be *really* slow and overload the remote storage service. This PR adds an option to not do GetFileSize(); instead it does GetChildren() for parent directory to check that all the expected sst files are at least present, but doesn't check their sizes.

We can't just disable paranoid_checks instead because paranoid_checks do a few other important things: make the DB read-only on write errors, print error messages on read errors, etc.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6353

Test Plan: ran the added sanity check unit test. Will try it out in a LogDevice test cluster where the GetFileSize() calls are causing a lot of trouble.

Differential Revision: D19656425

Pulled By: al13n321

fbshipit-source-id: c2c421b367633033760d1f56747bad206d1fbf82
2020-02-04 01:27:26 -08:00
Maysam Yabandeh eff5e076f5 unordered_write incompatible with max_successive_merges (#6284)
Summary:
unordered_write is incompatible with non-zero max_successive_merges. Although we check this at runtime, we currently don't prevent the user from setting this combination in options. This has led to stress tests to fail with this combination is tried in ::SetOptions.
The patch fixes that and also reverts the changes performed by https://github.com/facebook/rocksdb/pull/6254, in which max_successive_merges was mistakenly declared incompatible with unordered_write.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6284

Differential Revision: D19356115

Pulled By: maysamyabandeh

fbshipit-source-id: f06dadec777622bd75f267361c022735cf8cecb6
2020-01-10 16:53:19 -08:00
Maysam Yabandeh 48a678b7c9 Prevent an incompatible combination of options (#6254)
Summary:
allow_concurrent_memtable_write is incompatible with non-zero max_successive_merges. Although we check this at runtime, we currently don't prevent the user from setting this combination in options. This has led to stress tests to fail with this combination is tried in ::SetOptions. The patch fixes that.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6254

Differential Revision: D19265819

Pulled By: maysamyabandeh

fbshipit-source-id: 47f2e2dc26fe0972c7152f4da15dadb9703f1179
2020-01-02 16:15:06 -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