Summary:
Since the number of range deletions are reported in
TableProperties, it is confusing to not report the number of merge
operands and point deletions as top-level properties; they are
accessible through the public API, but since they are not the "main"
properties, they do not appear in aggregated table properties, or the
string representation of table properties.
This change promotes those two property keys to
`rocksdb/table_properties.h`, adds corresponding uint64 members for
them, deprecates the old access methods `GetDeletedKeys()` and
`GetMergeOperands()` (though they are still usable for now), and removes
`InternalKeyPropertiesCollector`. The property key strings are the same
as before this change, so this should be able to read DBs written from older
versions (though I haven't tested this yet).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4594
Differential Revision: D12826893
Pulled By: abhimadan
fbshipit-source-id: 9e4e4fbdc5b0da161c89582566d184101ba8eb68
Summary:
Introduce `JemallocNodumpAllocator`, which allow exclusion of block cache usage from core dump. It utilize custom hook of jemalloc arena, and when jemalloc arena request memory from system, the allocator use the hook to set `MADV_DONTDUMP ` to the memory. The implementation is basically the same as `folly::JemallocNodumpAllocator`, except for some minor difference:
1. It only support jemalloc >= 5.0
2. When the allocator destruct, it explicitly destruct the corresponding arena via `arena.<i>.destroy` via `mallctl`.
Depending on #4502.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4534
Differential Revision: D10435474
Pulled By: yiwu-arbug
fbshipit-source-id: e80edea755d3853182485d2be710376384ce0bb4
Summary:
Rename the interface, as it is mean to be a generic interface for memory allocation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4590
Differential Revision: D10866340
Pulled By: yiwu-arbug
fbshipit-source-id: 85cb753351a40cb856c046aeaa3f3b369eef3d16
Summary:
`WritableFileWrapper` was missing some newer methods that were added to `WritableFile`. Without these functions, the missing wrapper methods would fallback to using the default implementations in WritableFile instead of using the corresponding implementations in, say, `PosixWritableFile` or `WinWritableFile`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4584
Differential Revision: D10559199
Pulled By: sagar0
fbshipit-source-id: 0d0f18a486aee727d5b8eebd3110a41988e27391
Summary:
Couple of very minor improvements (typos in comments, full qualification of class name, reordering members of a struct to make it smaller)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4564
Differential Revision: D10510183
Pulled By: maysamyabandeh
fbshipit-source-id: c7ddf9bfbf2db08cd31896c3fd93789d3fa68c8b
Summary:
Level compaction usually performs poorly when the writes so heavy that the level targets can't be guaranteed. With this improvement, we improve level_compaction_dynamic_level_bytes = true so that in the write heavy cases, the level multiplier can be slightly adjusted based on the size of L0.
We keep the behavior the same if number of L0 files is under 2X compaction trigger and the total size is less than options.max_bytes_for_level_base, so that unless write is so heavy that compaction cannot keep up, the behavior doesn't change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4338
Differential Revision: D9636782
Pulled By: siying
fbshipit-source-id: e27fc17a7c29c84b00064cc17536a01dacef7595
Summary:
Current implementation of perf context is level agnostic. Making it hard to do performance evaluation for the LSM tree. This PR adds `PerfContextByLevel` to decompose the counters by level.
This will be helpful when analyzing point and range query performance as well as tuning bloom filter
Also replaced __thread with thread_local keyword for perf_context
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4226
Differential Revision: D10369509
Pulled By: miasantreble
fbshipit-source-id: f1ced4e0de5fcebdb7f9cff36164516bc6382d82
Summary:
Using const string& can avoid one extra string copy. This PR addresses a recent comment made by siying on #3933.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4491
Differential Revision: D10381211
Pulled By: riversand963
fbshipit-source-id: 27fc2d65d84bc7cd07833c77cdc47f06dcfaeb31
Summary:
We would like to collect file-system-level statistics including file name, offset, length, return code, latency, etc., which requires to add callbacks to intercept file IO function calls when RocksDB is running.
To collect file-system-level statistics, users can inherit the class `EventListener`, as in `TestFileOperationListener `. Note that `TestFileOperationListener::ShouldBeNotifiedOnFileIO()` returns true.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3933
Differential Revision: D10219571
Pulled By: riversand963
fbshipit-source-id: 7acc577a2d31097766a27adb6f78eaf8b1e8ff15
Summary:
fix#4288
Add `OnCompactionBegin` support to `rocksdb::EventListener`.
Currently, we only have these three callbacks:
- OnFlushBegin
- OnFlushCompleted
- OnCompactionCompleted
As paolococchi requested in #4288 , and ajkr agreed, we should also support `OnCompactionBegin`.
This PR is a try to implement the support of `OnCompactionBegin`.
Hope it is useful to you.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4431
Differential Revision: D10055515
Pulled By: yiwu-arbug
fbshipit-source-id: 39c0f95f8e9ff1c7ca3a10787502a17f258d2334
Summary:
The controller you requested could not be found. PTAL
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4466
Differential Revision: D10241358
Pulled By: yiwu-arbug
fbshipit-source-id: 99664eb286860a6c8844d50efeb0ef6f0e10dd1e
Summary:
This is a conceptually simple change, but it touches many files to
pass the allocator through function calls.
We introduce CacheAllocator, which can be used by clients to configure
custom allocator for cache blocks. Our motivation is to hook this up
with folly's `JemallocNodumpAllocator`
(f43ce6d686/folly/experimental/JemallocNodumpAllocator.h),
but there are many other possible use cases.
Additionally, this commit cleans up memory allocation in
`util/compression.h`, making sure that all allocations are wrapped in a
unique_ptr as soon as possible.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4437
Differential Revision: D10132814
Pulled By: yiwu-arbug
fbshipit-source-id: be1343a4b69f6048df127939fea9bbc96969f564
Summary:
Previously `CompactFiles` with `CompressionType::kDisableCompressionOption` caused program to crash on assertion failure. This PR fixes the crash by adding support for that setting. Now, that setting will cause RocksDB to choose compression according to the column family's options.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4438
Differential Revision: D10115761
Pulled By: ajkr
fbshipit-source-id: a553c6fa76fa5b6f73b0d165d95640da6f454122
Summary:
Make the CompactOnDeletionCollectorFactory class public, and provide
methods to update the window size and deletion trigger params. These
will take effect on subsequent created SST files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4403
Differential Revision: D9976857
Pulled By: anand1976
fbshipit-source-id: 31dbf0511c12fa2bb9b2a7ba620079e0ee09cf48
Summary:
This commit implements automatic recovery from a Status::NoSpace() error
during background operations such as write callback, flush and
compaction. The broad design is as follows -
1. Compaction errors are treated as soft errors and don't put the
database in read-only mode. A compaction is delayed until enough free
disk space is available to accomodate the compaction outputs, which is
estimated based on the input size. This means that users can continue to
write, and we rely on the WriteController to delay or stop writes if the
compaction debt becomes too high due to persistent low disk space
condition
2. Errors during write callback and flush are treated as hard errors,
i.e the database is put in read-only mode and goes back to read-write
only fater certain recovery actions are taken.
3. Both types of recovery rely on the SstFileManagerImpl to poll for
sufficient disk space. We assume that there is a 1-1 mapping between an
SFM and the underlying OS storage container. For cases where multiple
DBs are hosted on a single storage container, the user is expected to
allocate a single SFM instance and use the same one for all the DBs. If
no SFM is specified by the user, DBImpl::Open() will allocate one, but
this will be one per DB and each DB will recover independently. The
recovery implemented by SFM is as follows -
a) On the first occurance of an out of space error during compaction,
subsequent
compactions will be delayed until the disk free space check indicates
enough available space. The required space is computed as the sum of
input sizes.
b) The free space check requirement will be removed once the amount of
free space is greater than the size reserved by in progress
compactions when the first error occured
c) If the out of space error is a hard error, a background thread in
SFM will poll for sufficient headroom before triggering the recovery
of the database and putting it in write-only mode. The headroom is
calculated as the sum of the write_buffer_size of all the DB instances
associated with the SFM
4. EventListener callbacks will be called at the start and completion of
automatic recovery. Users can disable the auto recov ery in the start
callback, and later initiate it manually by calling DB::Resume()
Todo:
1. More extensive testing
2. Add disk full condition to db_stress (follow-on PR)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4164
Differential Revision: D9846378
Pulled By: anand1976
fbshipit-source-id: 80ea875dbd7f00205e19c82215ff6e37da10da4a
Summary:
Please consider this small PR providing access to the `MemoryUsage::GetApproximateMemoryUsageByType` function in plain C API. Actually I'm working on Go application and now trying to investigate the reasons of high memory consumption (#4313). Go [wrappers](https://github.com/tecbot/gorocksdb) are built on the top of Rocksdb C API. According to the #706, `MemoryUsage::GetApproximateMemoryUsageByType` is considered as the best option to get database internal memory usage stats, but it wasn't supported in C API yet.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4340
Differential Revision: D9655135
Pulled By: ajkr
fbshipit-source-id: a3d2f3f47c143ae75862fbcca2f571ea1b49e14a
Summary:
TransactionOptions::skip_concurrency_control allows pessimistic transactions to skip the overhead of concurrency control. This could be as an optimization if the application knows that the transaction would not have any conflict with concurrent transactions. It is currently used during recovery assuming (i) application guarantees no conflict between prepared transactions in the WAL (ii) application guarantees that recovered transactions will be rolled back/commit before new transactions start.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4346
Differential Revision: D9759149
Pulled By: maysamyabandeh
fbshipit-source-id: f896e84fa58b0b584be904c7fd3883a41ea3215b
Summary:
As you know, almost all compilers support "pragma once" keyword instead of using include guards. To be keep consistency between header files, all header files are edited.
Besides this, try to fix some warnings about loss of data.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4339
Differential Revision: D9654990
Pulled By: ajkr
fbshipit-source-id: c2cf3d2d03a599847684bed81378c401920ca848
Summary:
`GetLiveFiles` and `GetLiveFilesMetadata` should return path relative to db path.
It is a separate issue when `path_relative` is false how can we return relative path. But `DBImpl::GetLiveFiles` don't handle it as well when there are multiple `db_paths`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4326
Differential Revision: D9545904
Pulled By: yiwu-arbug
fbshipit-source-id: 6762d879fcb561df2b612e6fdfb4a6b51db03f5d
Summary:
Basically at the moment it seems it's possible to cause write stall by calling flush (either manually vis DB::Flush(), or from Backup Engine directly calling FlushMemTable() while background flush may be already happening.
One of the ways to fix it is that in DBImpl::CompactRange() we already check for possible stall and delay flush if needed before we actually proceed to call FlushMemTable(). We can simply move this delay logic to separate method and call it from FlushMemTable.
This is draft patch, for first look; need to check tests/update SyncPoints and most certainly would need to add allow_write_stall method to FlushOptions().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4297
Differential Revision: D9420705
Pulled By: mikhail-antonov
fbshipit-source-id: f81d206b55e1d7b39e4dc64242fdfbceeea03fcc
Summary:
Memtables are selected for flushing by the flush job. Currently we
have listener which is invoked when memtables for a column family are
flushed. That listener does not indicate which memtable was flushed in
the notification. If clients want to know if particular data in the
memtable was retired, there is no straight forward way to know this.
This method will help users who implement memtablerep factory and extend
interface for memtablerep, to know if the data in the memtable was
retired.
Another option that was tried, was to depend on memtable destructor to
be called after flush to mark that data was persisted. This works all
the time but sometimes there can huge delays between actual flush
happening and memtable getting destroyed. Hence, if anyone who is
waiting for data to persist will have to wait that longer.
It is expected that anyone who is implementing this method to have
return quickly as it blocks RocksDB.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4304
Reviewed By: riversand963
Differential Revision: D9472312
Pulled By: gdrane
fbshipit-source-id: 8e693308dee749586af3a4c5d4fcf1fa5276ea4d
Summary:
We want to sample the file I/O issued by RocksDB and report the function calls. This requires us to include the file paths otherwise it's hard to tell what has been going on.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4039
Differential Revision: D8670178
Pulled By: riversand963
fbshipit-source-id: 97ee806d1c583a2983e28e213ee764dc6ac28f7a
Summary:
Transaction has had methods to deal with SavePoints already, but
was missing the PopSavePoint method provided by WriteBatch and
WriteBatchWithIndex.
This PR adds PopSavePoint to Transaction as well. Having the method
on Transaction-level too is useful for applications that repeatedly
execute a sequence of operations that normally succeed, but infrequently
need to get rolled back. Using SavePoints here is sensible, but as
operations normally succeed the application may pile up a lot of
useless SavePoints inside a Transaction, leading to slightly increased
memory usage for managing the unneeded SavePoints.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4256
Differential Revision: D9326932
Pulled By: yiwu-arbug
fbshipit-source-id: 53a0af18a6c7e87feff8a56f1f3eab9df7f371d6
Summary:
Add `--data_block_index_type` and `--data_block_hash_table_util_ratio` option to `db_bench`.
`--data_block_index_type` can be either of `binary` (default) or `binary_and_hash`;
`--data_block_hash_table_util_ratio` will be a double. The default value is `0.75`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4281
Differential Revision: D9361476
Pulled By: fgwu
fbshipit-source-id: dc53e01acef9db81b9eec5e8a96f3bc8ed718c10
Summary:
Right now, `ldb idump` may have memory out of control if there is a big range of tombstones. Add an option to cut maxinum number of keys in GetAllKeyVersions(), and push down --max_num_ikeys from ldb.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4271
Differential Revision: D9369149
Pulled By: siying
fbshipit-source-id: 7cbb797b7d2fa16573495a7e84937456d3ff25bf
Summary:
This PR addresses issue #3865 and implements the following approach to fix it:
- adds `MergeContext::GetOperandsDirectionForward` and `MergeContext::GetOperandsDirectionBackward` to query merge operands in a specific order
- `MergeContext::GetOperands` becomes a shortcut for `MergeContext::GetOperandsDirectionForward`
- pass `MergeContext::GetOperandsDirectionBackward` to `MergeOperator::ShouldMerge` and document the order
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4266
Differential Revision: D9360750
Pulled By: sagar0
fbshipit-source-id: 20cb73ff017760b062ecdcf4382560767086e092
Summary:
Add hash index support to data blocks, which helps to reduce the CPU utilization of point-lookup operations. This feature is backward compatible with the data block created without the hash index. It is disabled by default unless `BlockBasedTableOptions::data_block_index_type` is set to `data_block_index_type = kDataBlockBinaryAndHash.`
The DB size would be bigger with the hash index option as a hash table is added at the end of each data block. If the hash utilization ratio is 1:1, the space overhead is one byte per key. The hash table utilization ratio is adjustable using `BlockBasedTableOptions::data_block_hash_table_util_ratio`. A lower utilization ratio will improve more on the point-lookup efficiency, but take more space too.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4174
Differential Revision: D8965914
Pulled By: fgwu
fbshipit-source-id: 1c6bae5d1fc39c80282d8890a72e9e67bc247198
Summary:
Given that index value is a BlockHandle, which is basically an <offset, size> pair we can apply delta encoding on the values. The first value at each index restart interval encoded the full BlockHandle but the rest encode only the size. Refer to IndexBlockIter::DecodeCurrentValue for the detail of the encoding. This reduces the index size which helps using the block cache more efficiently. The feature is enabled with using format_version 4.
The feature comes with a bit of cpu overhead which should be paid back by the higher cache hits due to smaller index block size.
Results with sysbench read-only using 4k blocks and using 16 index restart interval:
Format 2:
19585 rocksdb read-only range=100
Format 3:
19569 rocksdb read-only range=100
Format 4:
19352 rocksdb read-only range=100
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3983
Differential Revision: D8361343
Pulled By: maysamyabandeh
fbshipit-source-id: f882ee082322acac32b0072e2bdbb0b5f854e651
Summary:
This change allows using std::string_view objects directly in the
DB API:
db->Get(some_string_view_object, ...);
The conversion from std::string_view to rocksdb::Slice is done
automatically, thanks to the added constructor.
I'm stopping short of adding an implicit conversion operator
from rocksdb::Slice to std::string_view, as I don't think that's
a good idea for PinnableSlices.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4242
Differential Revision: D9224134
Pulled By: anand1976
fbshipit-source-id: f50aad04dd0b01737907c0fb88d495c83a81f4e4
Summary:
We add two subcommands `write_extern_sst` and `ingest_extern_sst` to ldb. This PR avoids changing existing code because we hope to cherry-pick to earlier releases to support compatibility check for external SST file ingestion.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4205
Differential Revision: D9112711
Pulled By: riversand963
fbshipit-source-id: 7cae88380d4de86da8440230e87eca66755648e4
Summary:
So that we can act accordingly on blob index entries
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4233
Differential Revision: D9190205
Pulled By: yiwu-arbug
fbshipit-source-id: e5b84d5b41e44fa7a76762f1f7b0305369bb3a0c
Summary:
Hi, it would be great if we could expose this API, so that LogDevice can use it to track the total size of trash files and alarm if it grows too large in relation to disk size. There's probably other customers that would be interested in this as well. :)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4206
Differential Revision: D9115516
Pulled By: gdavidsson
fbshipit-source-id: f34993a940e39cb0a0b544ae8298546499b7e047
Summary:
A framework for tracing and replaying RocksDB operations.
A binary trace file is created by capturing the DB operations, and it can be replayed back at the same rate using db_bench.
- Column-families are supported
- Multi-threaded tracing is supported.
- TraceReader and TraceWriter are exposed to the user, so that tracing to various destinations can be enabled (say, to other messaging/logging services). By default, a FileTraceReader and FileTraceWriter are implemented to capture to a file and replay from it.
- This is not yet ideal to be enabled in production due to large performance overhead, but it can be safely tried out in a shadow setup, say, for analyzing RocksDB operations.
Currently supported DB operations:
- Writes:
-- Put
-- Merge
-- Delete
-- SingleDelete
-- DeleteRange
-- Write
- Reads:
-- Get (point lookups)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3837
Differential Revision: D7974837
Pulled By: sagar0
fbshipit-source-id: 8ec65aaf336504bc1f6ed0feae67f6ed5ef97a72
Summary:
RocksDB used to store global_seqno in external SST files written by
SstFileWriter. During file ingestion, RocksDB uses `pwrite` to update the
`global_seqno`. Since random write is not supported in some non-POSIX compliant
file systems, external SST file ingestion is not supported on these file
systems. To address this limitation, we no longer update `global_seqno` during
file ingestion. Later RocksDB uses the MANIFEST and other information in table
properties to deduce global seqno for externally-ingested SST files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4172
Differential Revision: D8961465
Pulled By: riversand963
fbshipit-source-id: 4382ec85270a96be5bc0cf33758ca2b167b05071
Summary:
Added DataBlockIndexType option in BlockBasedTableOptions.
```
enum DataBlockIndexType : char {
kDataBlockBinarySearch = 0, // traditional block type
kDataBlockHashIndex = 1, // additional hash index appended to the end.
};
```
The default type is the traditional binary seek option: `kDataBlockBinarySearch`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4150
Differential Revision: D8895958
Pulled By: fgwu
fbshipit-source-id: 480adef48104cf11d30db3bad9a73f98b4a80c10
Summary:
The inline doc was incorrectly mentioned a return status while the function does not return a value.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4196
Differential Revision: D9030927
Pulled By: maysamyabandeh
fbshipit-source-id: 07c34dc6bf521021bf790ac1bfedb676171129ec
Summary:
max_total_wal_size takes effect only when there are more than one column families. The patch clarify that in the inline docs
Closes https://github.com/facebook/rocksdb/issues/4180
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4194
Differential Revision: D9028767
Pulled By: maysamyabandeh
fbshipit-source-id: 8d730ca7f15e76e7ee9ff88b2b48030b2d1b7078
Summary:
Given that we have cut 5.15, we should bump the version number to the next
version, i.e. 5.16.
Also update HISTORY.md
cc sagar0
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4176
Differential Revision: D8977965
Pulled By: riversand963
fbshipit-source-id: 481d75d2f446946f0eb2afb7e94ef894c8c87e1e
Summary:
This adds support for writing unprepared batches based on size defined in `TransactionOptions::max_write_batch_size`. This is done by overriding methods that modify data (Put/Delete/SingleDelete/Merge) and checking first if write batch size has exceeded threshold. If so, the write batch is written to DB as an unprepared batch.
Support for Commit/Rollback for unprepared batch is added as well. This has been done by simply extending the WritePrepared Commit/Rollback logic to take care of all unprep_seq numbers either when updating prepare heap, or adding to commit map. For updating the commit map, this logic exists inside `WriteUnpreparedCommitEntryPreReleaseCallback`.
A test change was also made to have transactions unregister themselves when committing without prepare. This is because with write unprepared, there may be unprepared entries (which act similarly to prepared entries) already when a commit is done without prepare.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4104
Differential Revision: D8785717
Pulled By: lth
fbshipit-source-id: c02006e281ec1ce00f628e2a7beec0ee73096a91
Summary:
The member msgs of class Status contains all types of status messages.
When users dump a Status object, msgs will confuse users. So move it out
of class Status by making it as file-local static variable.
Closes#3831 .
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4144
Differential Revision: D8941419
Pulled By: sagar0
fbshipit-source-id: 56b0510258465ff26db15aa6b04e01532e053e3d
Summary:
Fixes#3391.
This change adds a `DeleteRange` method to `SstFileWriter` and adds
support for ingesting SSTs with range deletion tombstones. This is
important for applications that need to atomically ingest SSTs while
clearing out any existing keys in a given key range.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3778
Differential Revision: D8821836
Pulled By: anand1976
fbshipit-source-id: ca7786c1947ff129afa703dab011d524c7883844
Summary:
- Avoid `strdup` to use jemalloc on Windows
- Use `size_t` for consistency
- Add GCC 8 to Travis
- Add CMAKE_BUILD_TYPE=Release to Travis
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3433
Differential Revision: D6837948
Pulled By: sagar0
fbshipit-source-id: b8543c3a4da9cd07ee9a33f9f4623188e233261f
Summary:
Right now slow deletion with ftruncate doesn't work well with checkpoints because it ruin hard linked files in checkpoints. To fix it, check the file has no other hard link before ftruncate it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4093
Differential Revision: D8730360
Pulled By: siying
fbshipit-source-id: 756eea5bce8a87b9a2ea3a5bfa190b2cab6f75df
Summary:
This adds support for recovering WriteUnprepared transactions through the following changes:
- The information in `RecoveredTransaction` is extended so that it can reference multiple batches.
- `MarkBeginPrepare` is extended with a bool indicating whether it is an unprepared begin, and this is passed down to `InsertRecoveredTransaction` to indicate whether the current transaction is prepared or not.
- `WriteUnpreparedTxnDB::Initialize` is overridden so that it will rollback unprepared transactions from the recovered transactions. This can be done without updating the prepare heap/commit map, because this is before the DB has finished initializing, and after writing the rollback batch, those data structures should not contain information about the rolled back transaction anyway.
Commit/Rollback of live transactions is still unimplemented and will come later.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4078
Differential Revision: D8703382
Pulled By: lth
fbshipit-source-id: 7e0aada6c23bd39299f1f20d6c060492e0e6b60a
Summary:
This was caught by crash test, and the following is a simple way to reproduce it and verify the fix.
One way to trigger this code path is to use the following configuration:
- Compress SST file
- Enable direct IO and prefetch buffer
- Do NOT use compressed block cache
Closes https://github.com/facebook/rocksdb/pull/4096
Differential Revision: D8742009
Pulled By: riversand963
fbshipit-source-id: f13381078bbb0dce92f60bd313a78ab602bcacd2
Summary:
Now by default, with NewSstFileManager, checkpoints may be corrupted. Disable this feature to avoid this issue.
Closes https://github.com/facebook/rocksdb/pull/4092
Differential Revision: D8729856
Pulled By: siying
fbshipit-source-id: 914c321d6eaf52d8c5981171322d85dd29088307
Summary:
This adds a new WAL marker of type kTypeBeginUnprepareXID.
Also, DBImpl now contains a field called batch_per_txn (meaning one WriteBatch per transaction, or possibly multiple WriteBatches). This would also indicate that this DB is using WriteUnprepared policy.
Recovery code would be able to make use of this extra field on DBImpl in a separate diff. For now, it is just used to determine whether the WAL is compatible or not.
Closes https://github.com/facebook/rocksdb/pull/4069
Differential Revision: D8675099
Pulled By: lth
fbshipit-source-id: ca27cae1738e46d65f2bb92860fc759deb874749
Summary:
Currently, if RocksDB encounters errors during a write operation (user requested or BG operations), it sets DBImpl::bg_error_ and fails subsequent writes. This PR allows the DB to be resumed for certain classes of errors. It consists of 3 parts -
1. Introduce Status::Severity in rocksdb::Status to indicate whether a given error can be recovered from or not
2. Refactor the error handling code so that setting bg_error_ and deciding on severity is in one place
3. Provide an API for the user to clear the error and resume the DB instance
This whole change is broken up into multiple PRs. Initially, we only allow clearing the error for Status::NoSpace() errors during background flush/compaction. Subsequent PRs will expand this to include more errors and foreground operations such as Put(), and implement a polling mechanism for out-of-space errors.
Closes https://github.com/facebook/rocksdb/pull/3997
Differential Revision: D8653831
Pulled By: anand1976
fbshipit-source-id: 6dc835c76122443a7668497c0226b4f072bc6afd
Summary:
This PR supports the group commit of multiple version edit entries corresponding to different column families. Column family drop/creation still cannot be grouped. This PR is a subset of [PR 3752](https://github.com/facebook/rocksdb/pull/3752).
Closes https://github.com/facebook/rocksdb/pull/3944
Differential Revision: D8432536
Pulled By: riversand963
fbshipit-source-id: 8f11bd05193b6c0d9272d82e44b676abfac113cb
Summary:
…ression
For `CompressionType` we have options `compression` and `bottommost_compression`. Thus, to make the compression options consitent with the compression type when bottommost_compression is enabled, we add the bottommost_compression_opts
Closes https://github.com/facebook/rocksdb/pull/3985
Reviewed By: riversand963
Differential Revision: D8385911
Pulled By: zhichao-cao
fbshipit-source-id: 07bc533dd61bcf1cef5927d8d62901c13d38d5fc
Summary:
- Summary
Add timestamp into the DeadlockInfo to store the timestamp when deadlock detected on the rocksdb side.
- Testplan:
`make check -j64`
Closes https://github.com/facebook/rocksdb/pull/4060
Differential Revision: D8655380
Pulled By: chouxi
fbshipit-source-id: f58e1aa5e09eb1d1eed0a181d4e2304aaf01efe8
Summary:
Various rearrangements of the cch maths failed or replacing = '\0' with
memset failed to convince the compiler it was nul terminated. So took
the perverse option of changing strncpy to strcpy.
Return null if memory couldn't be allocated.
util/status.cc: In static member function ‘static const char* rocksdb::Status::CopyState(const char*)’:
util/status.cc:28:15: error: ‘char* strncpy(char*, const char*, size_t)’ output truncated before terminating nul copying as many bytes from a string as its length [-Werror=stringop-truncation]
std::strncpy(result, state, cch - 1);
~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
util/status.cc:19:18: note: length computed here
std::strlen(state) + 1; // +1 for the null terminator
~~~~~~~~~~~^~~~~~~
cc1plus: all warnings being treated as errors
make: *** [Makefile:645: shared-objects/util/status.o] Error 1
closes#2705
Closes https://github.com/facebook/rocksdb/pull/3870
Differential Revision: D8594114
Pulled By: anand1976
fbshipit-source-id: ab20f3a456a711e4d29144ebe630e4fe3c99ec25
Summary:
This is implemented by extending ReadCallback with another function `MaxUnpreparedSequenceNumber` which returns the largest visible sequence number for the current transaction, if there is uncommitted data written to DB. Otherwise, it returns zero, indicating no uncommitted data.
There are the places where reads had to be modified.
- Get and Seek/Next was just updated to seek to max(snapshot_seq, MaxUnpreparedSequenceNumber()) instead, and iterate until a key was visible.
- Prev did not need need updates since it did not use the Seek to sequence number optimization. Assuming that locks were held when writing unprepared keys, and ValidateSnapshot runs, there should only be committed keys and unprepared keys of the current transaction, all of which are visible. Prev will simply iterate to get the last visible key.
- Reseeking to skip keys optimization was also disabled for write unprepared, since it's possible to hit the max_skip condition even while reseeking. There needs to be some way to resolve infinite looping in this case.
Closes https://github.com/facebook/rocksdb/pull/3955
Differential Revision: D8286688
Pulled By: lth
fbshipit-source-id: 25e42f47fdeb5f7accea0f4fd350ef35198caafe
Summary:
Add a new table property, rocksdb.num.range-deletions, which tracks the
number of range deletions in a block-based table. Range deletions are no
longer counted in rocksdb.num.entries; as discovered in PR #3778, there
are various code paths that implicitly assume that rocksdb.num.entries
counts only true keys, not range deletions.
/cc ajkr nvanbenschoten
Closes https://github.com/facebook/rocksdb/pull/4016
Differential Revision: D8527575
Pulled By: ajkr
fbshipit-source-id: 92e7edbe78fda53756a558013c9fb496e7764fd7
Summary:
Previously in https://github.com/facebook/rocksdb/pull/3601 bloom filter will only be checked if `prefix_extractor` in the mutable_cf_options matches the one found in the SST file.
This PR relaxes the requirement by checking if all keys in the range [user_key, iterate_upper_bound) all share the same prefix after transforming using the BF in the SST file. If so, the bloom filter is considered compatible and will continue to be looked at.
Closes https://github.com/facebook/rocksdb/pull/3899
Differential Revision: D8157459
Pulled By: miasantreble
fbshipit-source-id: 18d17cba56a1005162f8d5db7a27aba277089c41
Summary:
Top-level index in partitioned index/filter blocks are small and could be pinned in memory. So far we use that by cache_index_and_filter_blocks to false. This however make it difficult to keep account of the total memory usage. This patch introduces pin_top_level_index_and_filter which in combination with cache_index_and_filter_blocks=true keeps the top-level index in cache and yet pinned them to avoid cache misses and also cache lookup overhead.
Closes https://github.com/facebook/rocksdb/pull/4037
Differential Revision: D8596218
Pulled By: maysamyabandeh
fbshipit-source-id: 3a5f7f9ca6b4b525b03ff6bd82354881ae974ad2
Summary:
Add a new DB property to DB::GetProperty(), which returns the option.statistics. Test is updated to pass.
Closes https://github.com/facebook/rocksdb/pull/3966
Differential Revision: D8311139
Pulled By: zhichao-cao
fbshipit-source-id: ea78f4727358c807b0e5a0ea62e09defb10ad9ac
Summary:
Index blocks have the same format as data blocks. The keys therefore similarly to the keys in the data blocks are internal keys, which means that in addition to the user key it also has 8 bytes that encodes sequence number and value type. This extra 8 bytes however is not necessary in index blocks since the index keys act as an separator between two data blocks. The only exception is when the last key of a block and the first key of the next block share the same user key, in which the sequence number is required to act as a separator.
The patch excludes the sequence from index keys only if the above special case does not happen for any of the index keys. It then records that in the property block. The reader looks at the property block to see if it should expect sequence numbers in the keys of the index block.s
Closes https://github.com/facebook/rocksdb/pull/3894
Differential Revision: D8118775
Pulled By: maysamyabandeh
fbshipit-source-id: 915479f028b5799ca91671d67455ecdefbd873bd
Summary:
Add flush_before_backup to rocksdb_backup_engine_create_new_backup. make c api able to control the flush before backup behavior.
Closes https://github.com/facebook/rocksdb/pull/3897
Differential Revision: D8157676
Pulled By: ajkr
fbshipit-source-id: 88998c62f89f087bf8672398fd7ddafabbada505
Summary:
Implement midpoint insertion strategy where new blocks will be insert to the middle of LRU list, then move the head on the first hit in cache.
Closes https://github.com/facebook/rocksdb/pull/3877
Differential Revision: D8100895
Pulled By: yiwu-arbug
fbshipit-source-id: f4bd83cb8be469e5d02072cfc8bd66011391f3da
Summary:
Catch up with Posix features
NewWritableRWFile must fail when file does not exists
Implement Env::Truncate()
Adjust Env options optimization functions
Implement MemoryMappedBuffer on Windows.
Closes https://github.com/facebook/rocksdb/pull/3857
Differential Revision: D8053610
Pulled By: ajkr
fbshipit-source-id: ccd0d46c29648a9f6f496873bc1c9d6c5547487e
Summary:
Previously we were using -1 as the default for every library, which was legacy from our zlib options. That worked for a while, but after zstd introduced a146ee04ae, it started giving poor compression ratios by default in zstd.
This PR adds a constant to RocksDB public API, `CompressionOptions::kDefaultCompressionLevel`, which will get translated to the default value specific to the compression library being used in "util/compression.h". The constant uses a number that appears to be larger than any library's maximum compression level.
Closes https://github.com/facebook/rocksdb/pull/3895
Differential Revision: D8125780
Pulled By: ajkr
fbshipit-source-id: 2db157a89118cd4f94577c2f4a0a5ff31c8391c6
Summary:
Fix Issue #3771 : Check for nullptr in Slice constructor
Slice ctor checks for nullptr and creates empty string if the string does not exist
Closes https://github.com/facebook/rocksdb/pull/3887
Differential Revision: D8098852
Pulled By: ajkr
fbshipit-source-id: 04471077defa9776ce7b8c389a61312ce31002fb
Summary:
Change `keys_` from `set<string>` to `vector<set<string>>` so that each column
family's keys are stored in one set.
ajkr When you have a chance, can you PTAL? Thanks!
Closes https://github.com/facebook/rocksdb/pull/3871
Differential Revision: D8056447
Pulled By: riversand963
fbshipit-source-id: 650d0f9cad02b1bc005fc329ad76edbf053e6386
Summary:
Previously it only printed percentiles, even though our histogram keeps track of count and sum (and more). There have been many times we want to know more than the percentiles. For example, we currently want sum of "rocksdb.compression.times.nanos" and sum of "rocksdb.decompression.times.nanos", which would allow us to know the relative cost of compression vs decompression.
This PR adds count and sum to the string printed by `StatisticsImpl::ToString`. This is a bit risky as there are definitely parsers assuming the old format. I will mention it in HISTORY.md and hope for the best...
Closes https://github.com/facebook/rocksdb/pull/3863
Differential Revision: D8038831
Pulled By: ajkr
fbshipit-source-id: 0465b72e4b0cbf18ef965f4efe402601d16d5b5c
Summary:
In the past, the default value of max_manifest_file_size is uint64_t::MAX,
allowing a long running RocksDB process to grow its MANIFEST file to take up
the entire disk, as reported in [issue 3851](https://github.com/facebook/rocksdb/issues/3851). It is reasonable and common to provide a default non-max value for this option. Therefore, I set the value to 1GB.
siying miasantreble Please let me know whether this looks good to you. Thanks!
Closes https://github.com/facebook/rocksdb/pull/3867
Differential Revision: D8051524
Pulled By: riversand963
fbshipit-source-id: 50251f0804b1fa933a19a30d19d261ea8b9d2b72
Summary:
Before this PR, Iterator/InternalIterator may simultaneously have non-ok status() and Valid() = true. That state means that the last operation failed, but the iterator is nevertheless positioned on some unspecified record. Likely intended uses of that are:
* If some sst files are corrupted, a normal iterator can be used to read the data from files that are not corrupted.
* When using read_tier = kBlockCacheTier, read the data that's in block cache, skipping over the data that is not.
However, this behavior wasn't documented well (and until recently the wiki on github had misleading incorrect information). In the code there's a lot of confusion about the relationship between status() and Valid(), and about whether Seek()/SeekToLast()/etc reset the status or not. There were a number of bugs caused by this confusion, both inside rocksdb and in the code that uses rocksdb (including ours).
This PR changes the convention to:
* If status() is not ok, Valid() always returns false.
* Any seek operation resets status. (Before the PR, it depended on iterator type and on particular error.)
This does sacrifice the two use cases listed above, but siying said it's ok.
Overview of the changes:
* A commit that adds missing status checks in MergingIterator. This fixes a bug that actually affects us, and we need it fixed. `DBIteratorTest.NonBlockingIterationBugRepro` explains the scenario.
* Changes to lots of iterator types to make all of them conform to the new convention. Some bug fixes along the way. By far the biggest changes are in DBIter, which is a big messy piece of code; I tried to make it less big and messy but mostly failed.
* A stress-test for DBIter, to gain some confidence that I didn't break it. It does a few million random operations on the iterator, while occasionally modifying the underlying data (like ForwardIterator does) and occasionally returning non-ok status from internal iterator.
To find the iterator types that needed changes I searched for "public .*Iterator" in the code. Here's an overview of all 27 iterator types:
Iterators that didn't need changes:
* status() is always ok(), or Valid() is always false: MemTableIterator, ModelIter, TestIterator, KVIter (2 classes with this name anonymous namespaces), LoggingForwardVectorIterator, VectorIterator, MockTableIterator, EmptyIterator, EmptyInternalIterator.
* Thin wrappers that always pass through Valid() and status(): ArenaWrappedDBIter, TtlIterator, InternalIteratorFromIterator.
Iterators with changes (see inline comments for details):
* DBIter - an overhaul:
- It used to silently skip corrupted keys (`FindParseableKey()`), which seems dangerous. This PR makes it just stop immediately after encountering a corrupted key, just like it would for other kinds of corruption. Let me know if there was actually some deeper meaning in this behavior and I should put it back.
- It had a few code paths silently discarding subiterator's status. The stress test caught a few.
- The backwards iteration code path was expecting the internal iterator's set of keys to be immutable. It's probably always true in practice at the moment, since ForwardIterator doesn't support backwards iteration, but this PR fixes it anyway. See added DBIteratorTest.ReverseToForwardBug for an example.
- Some parts of backwards iteration code path even did things like `assert(iter_->Valid())` after a seek, which is never a safe assumption.
- It used to not reset status on seek for some types of errors.
- Some simplifications and better comments.
- Some things got more complicated from the added error handling. I'm open to ideas for how to make it nicer.
* MergingIterator - check status after every operation on every subiterator, and in some places assert that valid subiterators have ok status.
* ForwardIterator - changed to the new convention, also slightly simplified.
* ForwardLevelIterator - fixed some bugs and simplified.
* LevelIterator - simplified.
* TwoLevelIterator - changed to the new convention. Also fixed a bug that would make SeekForPrev() sometimes silently ignore errors from first_level_iter_.
* BlockBasedTableIterator - minor changes.
* BlockIter - replaced `SetStatus()` with `Invalidate()` to make sure non-ok BlockIter is always invalid.
* PlainTableIterator - some seeks used to not reset status.
* CuckooTableIterator - tiny code cleanup.
* ManagedIterator - fixed some bugs.
* BaseDeltaIterator - changed to the new convention and fixed a bug.
* BlobDBIterator - seeks used to not reset status.
* KeyConvertingIterator - some small change.
Closes https://github.com/facebook/rocksdb/pull/3810
Differential Revision: D7888019
Pulled By: al13n321
fbshipit-source-id: 4aaf6d3421c545d16722a815b2fa2e7912bc851d
Summary:
The patch clarifies the ownership of the root db after TransactionDB::Open. If it is a success the ownership if with the TransactionDB, and the root db will be deleted when the destructor of the base class, StackableDB, is called. If it is failure, the temporarily created root db will also be deleted properly.
The patch also includes lots of useful formatting changes.
Closes https://github.com/facebook/rocksdb/pull/3714 upon which this patch is built.
Closes https://github.com/facebook/rocksdb/pull/3806
Differential Revision: D7878010
Pulled By: maysamyabandeh
fbshipit-source-id: f54f3942e29434143ae5a2423ceec9c7072cd4c2
Summary:
Previously `DBOptions::use_direct_io_for_flush_and_compaction=true` combined with `DBOptions::use_direct_reads=false` could cause RocksDB to simultaneously read from two file descriptors for the same file, where background reads used direct I/O and foreground reads used buffered I/O. Our measurements found this mixed-mode I/O negatively impacted foreground read perf, compared to when only buffered I/O was used.
This PR makes the mixed-mode I/O situation impossible by repurposing `DBOptions::use_direct_io_for_flush_and_compaction` to only apply to background writes, and `DBOptions::use_direct_reads` to apply to all reads. There is no risk of direct background direct writes happening simultaneously with buffered reads since we never read from and write to the same file simultaneously.
Closes https://github.com/facebook/rocksdb/pull/3829
Differential Revision: D7915443
Pulled By: ajkr
fbshipit-source-id: 78bcbf276449b7e7766ab6b0db246f789fb1b279
Summary:
- Original commit: a4fb1f8c04
- Revert commit (we reverted as a quick fix to get crash tests passing): 6afe22db2e
This PR includes the contents of the original commit plus two bug fixes, which are:
- In whitebox crash test, only set `--expected_values_path` for `db_stress` runs in the first half of the crash test's duration. In the second half, a fresh DB is created for each `db_stress` run, so we cannot maintain expected state across `db_stress` runs.
- Made `Exists()` return true for `UNKNOWN_SENTINEL` values. I previously had an assert in `Exists()` that value was not `UNKNOWN_SENTINEL`. But it is possible for post-crash-recovery expected values to be `UNKNOWN_SENTINEL` (i.e., if the crash happens in the middle of an update), in which case this assertion would be tripped. The effect of returning true in this case is there may be cases where a `SingleDelete` deletes no data. But if we had returned false, the effect would be calling `SingleDelete` on a key with multiple older versions, which is not supported.
Closes https://github.com/facebook/rocksdb/pull/3793
Differential Revision: D7811671
Pulled By: ajkr
fbshipit-source-id: 67e0295bfb1695ff9674837f2e05bb29c50efc30
Summary:
A minor change: I wrapped TransactionLogIterator for the C API.
I needed that for the golang binding.
Closes https://github.com/facebook/rocksdb/pull/3304
Differential Revision: D6628736
Pulled By: miasantreble
fbshipit-source-id: 3374f3c64b1d7b225696b8767090917761e2f30a
Summary:
crash-recovery verification is failing in the whitebox testing, which may or may not be a valid correctness issue -- need more time to investigate. In the meantime, reverting so we don't mask other failures.
Closes https://github.com/facebook/rocksdb/pull/3786
Differential Revision: D7794516
Pulled By: ajkr
fbshipit-source-id: 28ccdfdb9ec9b3b0fb08c15cbf9d2e282201ff33
Summary:
Sometimes we want to compact files as fast as possible, but don't want to set a large `max_subcompactions` in the `DBOptions` by default.
I add a `max_subcompactions` options to `CompactionOptions` so that we can choose a proper concurrency dynamically.
Closes https://github.com/facebook/rocksdb/pull/3775
Differential Revision: D7792357
Pulled By: ajkr
fbshipit-source-id: 94f54c3784dce69e40a229721a79a97e80cd6a6c
Summary:
This change adds a virtual `Truncate` method to `Env`, which truncates
the named file to the specified size. At the moment, this is only
supported for `MockEnv`, but other `Env's` could be extended to override
the method too. This is the same approach that methods like `LinkFile` and
`AreSameFile` have taken.
This is useful for any user of the in-memory `Env`. The implementation's
header is not exported, so before this change, it was impossible to
access it's already existing `Truncate` method.
Closes https://github.com/facebook/rocksdb/pull/3779
Differential Revision: D7785789
Pulled By: ajkr
fbshipit-source-id: 3bcdaeea7b7180529f7d9b496dc67b791a00bbf0
Summary:
In include/rocksdb/db.h, enum EntryType is redeclared even though
original declaration in types.h in included.
Closes https://github.com/facebook/rocksdb/pull/3766
Differential Revision: D7765504
Pulled By: anand1976
fbshipit-source-id: 622a8ecb306993915be1b9dd5cdd79dbc6a4ea05
Summary:
Previously, our `db_stress` tool held the expected state of the DB in-memory, so after crash-recovery, there was no way to verify data correctness. This PR adds an option, `--expected_values_file`, which specifies a file holding the expected values.
In black-box testing, the `db_stress` process can be killed arbitrarily, so updates to the `--expected_values_file` must be atomic. We achieve this by `mmap`ing the file and relying on `std::atomic<uint32_t>` for atomicity. Actually this doesn't provide a total guarantee on what we want as `std::atomic<uint32_t>` could, in theory, be translated into multiple stores surrounded by a mutex. We can verify our assumption by looking at `std::atomic::is_always_lock_free`.
For the `mmap`'d file, we didn't have an existing way to expose its contents as a raw memory buffer. This PR adds it in the `Env::NewMemoryMappedFileBuffer` function, and `MemoryMappedFileBuffer` class.
`db_crashtest.py` is updated to use an expected values file for black-box testing. On the first iteration (when the DB is created), an empty file is provided as `db_stress` will populate it when it runs. On subsequent iterations, that same filename is provided so `db_stress` can check the data is as expected on startup.
Closes https://github.com/facebook/rocksdb/pull/3629
Differential Revision: D7463144
Pulled By: ajkr
fbshipit-source-id: c8f3e82c93e045a90055e2468316be155633bd8b
Summary:
Background activities like compaction can negatively affect
latency of higher-priority tasks like request processing. To avoid this,
rocksdb already lowers the IO priority of background threads on Linux
systems. While this takes care of typical IO-bound systems, it does not
help much when CPU (temporarily) becomes the bottleneck. This is
especially likely when using more expensive compression settings.
This patch adds an API to allow for lowering the CPU priority of
background threads, modeled on the IO priority API. Benchmarks (see
below) show significant latency and throughput improvements when CPU
bound. As a result, workloads with some CPU usage bursts should benefit
from lower latencies at a given utilization, or should be able to push
utilization higher at a given request latency target.
A useful side effect is that compaction CPU usage is now easily visible
in common tools, allowing for an easier estimation of the contribution
of compaction vs. request processing threads.
As with IO priority, the implementation is limited to Linux, degrading
to a no-op on other systems.
Closes https://github.com/facebook/rocksdb/pull/3763
Differential Revision: D7740096
Pulled By: gwicke
fbshipit-source-id: e5d32373e8dc403a7b0c2227023f9ce4f22b413c
Summary:
There's a group of stats in PerfContext for profiling the write path. They break down the write time into WAL write, memtable insert, throttling, and everything else. We use these stats a lot for figuring out the cause of slow writes.
These stats got a bit out of date and are now categorizing some interesting things as "everything else", and also do some double counting. This PR fixes it and adds two new stats: time spent waiting for other threads of the batch group, and time spent waiting for scheduling flushes/compactions. Probably these will be enough to explain all the occasional abnormally slow (multiple seconds) writes that we're seeing.
Closes https://github.com/facebook/rocksdb/pull/3602
Differential Revision: D7251562
Pulled By: al13n321
fbshipit-source-id: 0a2d0f5a4fa5677455e1f566da931cb46efe2a0d
Summary:
1. Add a new ticker stat rocksdb.number.multiget.keys.found to track the
number of keys successfully read
2. Update rocksdb.memtable.hit/miss in DBImpl::MultiGet(). It was being done in
DBImpl::GetImpl(), but not MultiGet
Closes https://github.com/facebook/rocksdb/pull/3730
Differential Revision: D7677364
Pulled By: anand1976
fbshipit-source-id: af22bd0ef8ddc5cf2b4244b0a024e539fe48bca5
Summary:
Currently the partitioned index iterator creates a new ReadOptions which ignores the fill_cache config set to ReadOptions passed by the user. The patch propagates fill_cache from the user's ReadOptions to that of partition index iterator.
Also it clarifies the contract of fill_cache that i) it does not apply to filters, ii) it still charges block cache for the size of the data block, it still pin the block if it is already in the block cache.
Closes https://github.com/facebook/rocksdb/pull/3739
Differential Revision: D7678308
Pulled By: maysamyabandeh
fbshipit-source-id: 53ed96424ae922e499e2d4e3580ddc3f0db893da
Summary:
Previously threads were named "rocksdb:bg\<index in thread pool\>", so the first thread in all thread pools would be named "rocksdb:bg0". Users want to be able to distinguish threads used for flush (high-pri) vs regular compaction (low-pri) vs compaction to bottom-level (bottom-pri). So I changed the thread naming convention to include the thread-pool priority.
Closes https://github.com/facebook/rocksdb/pull/3702
Differential Revision: D7581415
Pulled By: ajkr
fbshipit-source-id: ce04482b6acd956a401ef22dc168b84f76f7d7c1
Summary:
When there are many range deletions in a range, we want to trigger manual compaction on this range to reclaim disk space as soon as possible and speed up read.
After this change, we can collect informations of range deletions and store them into user properties which can guide our manual compaction.
Closes https://github.com/facebook/rocksdb/pull/3695
Differential Revision: D7570322
Pulled By: ajkr
fbshipit-source-id: c358fa43b0aac6cc954d2eadc7d3bd8015373369
Summary:
This PR comments out the rest of the unused arguments which allow us to turn on the -Wunused-parameter flag. This is the second part of a codemod relating to https://github.com/facebook/rocksdb/pull/3557.
Closes https://github.com/facebook/rocksdb/pull/3662
Differential Revision: D7426121
Pulled By: Dayvedde
fbshipit-source-id: 223994923b42bd4953eb016a0129e47560f7e352
Summary:
This is a hack as temporary fix of MyRocks with rollbacking the merge operands. The way MyRocks uses merge operands is without protection of locks, which violates the assumption behind the rollback algorithm. They are ok with not being rolled back as it would just create a gap in the autoincrement column. The hack add an option to disable the rollback of merge operands by default and only enables it to let the unit test pass.
Closes https://github.com/facebook/rocksdb/pull/3711
Differential Revision: D7597177
Pulled By: maysamyabandeh
fbshipit-source-id: 544be0f666c7e7abb7f651ec8b23124e05056728
Summary:
Add `compaction_reason` as part of event log for event `compaction started`.
Add counters for each `CompactionReason`.
Closes https://github.com/facebook/rocksdb/pull/3679
Differential Revision: D7550348
Pulled By: riversand963
fbshipit-source-id: a19cff3a678c785aa5ef41aac78b9a5968fcc34d
Summary:
1. Remove redundant text.
2. Make terminology consistent across all comments and doc of RocksDB. Also do
our best to conform to conventions. Specifically, use 'callback' instead of
'call-back' [wikipedia](https://en.wikipedia.org/wiki/Callback_(computer_programming)).
Closes https://github.com/facebook/rocksdb/pull/3693
Differential Revision: D7560396
Pulled By: riversand963
fbshipit-source-id: ba8c251c487f4e7d1872a1a8dc680f9e35a6ffb8
Summary:
Adding some stats that would be helpful to monitor if the DB has gone to unlikely stats that would hurt the performance. These are mostly when we end up needing to acquire a mutex.
Closes https://github.com/facebook/rocksdb/pull/3683
Differential Revision: D7529393
Pulled By: maysamyabandeh
fbshipit-source-id: f7d36279a8f39bd84d8ddbf64b5c97f670c5d6d9
Summary:
Currently dump_wal cannot print the prepared records from the WAL that is generated by WRITE_PREPARED write policy since the default reaction of the handler is to return NotSupported if markers of WRITE_PREPARED are encountered. This patch enables the admin to pass --write_committed=false option, which will be accordingly passed to the handler. Note that DBFileDumperCommand and DBDumperCommand are still not updated by this patch but firstly they are not urgent and secondly we need to revise this approach later when we also add WRITE_UNPREPARED markers so I leave it for future work.
Tested by running it on a WAL generated by WRITE_PREPARED:
$ ./ldb dump_wal --walfile=/dev/shm/dbbench/000003.log | grep BEGIN_PREARE | head -1
1,2,70,0,BEGIN_PREARE
$ ./ldb dump_wal --walfile=/dev/shm/dbbench/000003.log --write_committed=false | grep BEGIN_PREARE | head -1
1,2,70,0,BEGIN_PREARE PUT(0) : 0x30303031313330313938 PUT(0) : 0x30303032353732313935 END_PREPARE(0x74786E31313535383434323738303738363938313335312D30)
Closes https://github.com/facebook/rocksdb/pull/3682
Differential Revision: D7522090
Pulled By: maysamyabandeh
fbshipit-source-id: a0332207261c61e18b2f9dfbe9feecd9a1339aca
Summary:
When `max_valid_backups_to_open` is set, the `BackupEngine` doesn't know about the files referenced by existing backups. This PR prevents us from deleting valid files when that option is set, in cases where we are unable to accurately determine refcount. There are warnings logged when we may miss deleting unreferenced files, and a recommendation in the header for users to periodically unset this option and run a full `GarbageCollect`.
Closes https://github.com/facebook/rocksdb/pull/3518
Differential Revision: D7008331
Pulled By: ajkr
fbshipit-source-id: 87907f964dc9716e229d08636a895d2fc7b72305
Summary:
In this change, an option to set different paths for different column families is added.
This option is set via cf_paths setting of ColumnFamilyOptions. This option will work in a similar fashion to db_paths setting. Cf_paths is a vector of Dbpath values which contains a pair of the absolute path and target size. Multiple levels in a Column family can go to different paths if cf_paths has more than one path.
To maintain backward compatibility, if cf_paths is not specified for a column family, db_paths setting will be used. Note that, if db_paths setting is also not specified, RocksDB already has code to use db_name as the only path.
Changes :
1) A new member "cf_paths" is added to ImmutableCfOptions. This is set, based on cf_paths setting of ColumnFamilyOptions and db_paths setting of ImmutableDbOptions. This member is used to identify the path information whenever files are accessed.
2) Validation checks are added for cf_paths setting based on existing checks for db_paths setting.
3) DestroyDB, PurgeObsoleteFiles etc. are edited to support multiple cf_paths.
4) Unit tests are added appropriately.
Closes https://github.com/facebook/rocksdb/pull/3102
Differential Revision: D6951697
Pulled By: ajkr
fbshipit-source-id: 60d2262862b0a8fd6605b09ccb0da32bb331787d
Summary:
Adds two stats to allow us measuring the false positive rate of full filters:
- The total count of positives: rocksdb.bloom.filter.full.positive
- The total count of true positives: rocksdb.bloom.filter.full.true.positive
Not the term "full" in the stat name to indicate that they are meaningful in full filters. block-based filters are to be deprecated soon and supporting it is not worth the the additional cost of if-then-else branches.
Closes#3680
Tested by:
$ ./db_bench -benchmarks=fillrandom -db /dev/shm/rocksdb-tmpdb --num=1000000 -bloom_bits=10
$ ./db_bench -benchmarks="readwhilewriting" -db /dev/shm/rocksdb-tmpdb --statistics -bloom_bits=10 --duration=60 --num=2000000 --use_existing_db 2>&1 > /tmp/full.log
$ grep filter.full /tmp/full.log
rocksdb.bloom.filter.full.positive COUNT : 3628593
rocksdb.bloom.filter.full.true.positive COUNT : 3536026
which gives the false positive rate of 2.5%
Closes https://github.com/facebook/rocksdb/pull/3681
Differential Revision: D7517570
Pulled By: maysamyabandeh
fbshipit-source-id: 630ab1a473afdce404916d297035b6318de4c052
Summary:
This change models Optimistic Tx db after Pessimistic TX db. The motivation for this change is to make the ptr polymorphic so it can be held by the same raw or smart ptr.
Currently, due to the inheritance of the Opt Tx db not being rooted in the manner of Pess Tx from a single DB root it is more difficult to write clean code and have clear ownership of the database in cases when options dictate instantiate of plan DB, Pess Tx DB or Opt tx db.
Closes https://github.com/facebook/rocksdb/pull/3566
Differential Revision: D7184502
Pulled By: yiwu-arbug
fbshipit-source-id: 31d06efafd79497bb0c230e971857dba3bd962c3
Summary:
Level Compaction with TTL.
As of today, a file could exist in the LSM tree without going through the compaction process for a really long time if there are no updates to the data in the file's key range. For example, in certain use cases, the keys are not actually "deleted"; instead they are just set to empty values. There might not be any more writes to this "deleted" key range, and if so, such data could remain in the LSM for a really long time resulting in wasted space.
Introducing a TTL could solve this problem. Files (and, in turn, data) older than TTL will be scheduled for compaction when there is no other background work. This will make the data go through the regular compaction process and get rid of old unwanted data.
This also has the (good) side-effect of all the data in the non-bottommost level being newer than ttl, and all data in the bottommost level older than ttl. It could lead to more writes while reducing space.
This functionality can be controlled by the newly introduced column family option -- ttl.
TODO for later:
- Make ttl mutable
- Extend TTL to Universal compaction as well? (TTL is already supported in FIFO)
- Maybe deprecate CompactionOptionsFIFO.ttl in favor of this new ttl option.
Closes https://github.com/facebook/rocksdb/pull/3591
Differential Revision: D7275442
Pulled By: sagar0
fbshipit-source-id: dcba484717341200d419b0953dafcdf9eb2f0267
Summary:
Updated comments around AllowSingleOperand.
Reason: A couple of users were confused and encountered issues due to no overriding PartialMerge with AllowSingleOperand=true.
I'll also look into modifying the default merge operator implementation so that overriding PartialMerge is not mandatory when AllowSingleOp=true.
Closes https://github.com/facebook/rocksdb/pull/3659
Differential Revision: D7422691
Pulled By: sagar0
fbshipit-source-id: 3d075a6ced0120f5d65cb7ae5412936f1862f342
Summary:
Provide a block_align option in BlockBasedTableOptions to allow
alignment of SST file data blocks. This will avoid higher
IOPS/throughput load due to < 4KB data blocks spanning 2 4KB pages.
When this option is set to true, the block alignment is set to lower of
block size and 4KB.
Closes https://github.com/facebook/rocksdb/pull/3502
Differential Revision: D7400897
Pulled By: anand1976
fbshipit-source-id: 04cc3bd144e88e3431a4f97604e63ad7a0f06d44
Summary:
Summary
========
`InlineSkipList<>::Insert` takes the `key` parameter as a C-string. Then, it performs multiple comparisons with it requiring the `GetLengthPrefixedSlice()` to be spawn in `MemTable::KeyComparator::operator()(const char* prefix_len_key1, const char* prefix_len_key2)` on the same data over and over. The patch tries to optimize that.
Rough performance comparison
=====
Big keys, no compression.
```
$ ./db_bench --writes 20000000 --benchmarks="fillrandom" --compression_type none -key_size 256
(...)
fillrandom : 4.222 micros/op 236836 ops/sec; 80.4 MB/s
```
```
$ ./db_bench --writes 20000000 --benchmarks="fillrandom" --compression_type none -key_size 256
(...)
fillrandom : 4.064 micros/op 246059 ops/sec; 83.5 MB/s
```
TODO
======
In ~~a separated~~ this PR:
- [x] Go outside the write path. Maybe even eradicate the C-string-taking variant of `KeyIsAfterNode` entirely.
- [x] Try to cache the transformations applied by `KeyComparator` & friends in situations where we havy many comparisons with the same key.
Closes https://github.com/facebook/rocksdb/pull/3516
Differential Revision: D7059300
Pulled By: ajkr
fbshipit-source-id: 6f027dbb619a488129f79f79b5f7dbe566fb2dbb
Summary:
Add `bytes_max_delete_chunk` in SstFileManager so that we can drop a large file in multiple batches.
Closes https://github.com/facebook/rocksdb/pull/3640
Differential Revision: D7358679
Pulled By: siying
fbshipit-source-id: ef17f0da2f5723dbece2669485a9b91b3edc0bb7
Summary:
This pull request exposes the interface of PerfContext as C API
Closes https://github.com/facebook/rocksdb/pull/3607
Differential Revision: D7294225
Pulled By: ajkr
fbshipit-source-id: eddcfbc13538f379950b2c8b299486695ffb5e2c
Summary:
This is a small API extension to allow the CompactFiles method to return the names of files that were created during the compaction.
Closes https://github.com/facebook/rocksdb/pull/3608
Differential Revision: D7275789
Pulled By: siying
fbshipit-source-id: 1ec0c3954a0f10cd877efb5f29f9be6c7b59e9ba
Summary:
We missed updating version.h on master when cutting 5.11.fb and 5.12.fb branches. It should be the same as the version in the latest release branch (or should it be one more?).
I noticed this when trying to run some upgrade/downgrade tests from 5.11 to some new code on master.
Closes https://github.com/facebook/rocksdb/pull/3611
Differential Revision: D7282917
Pulled By: sagar0
fbshipit-source-id: 205ee75b77c5b6bbcea95a272760b427025a4aba
Summary:
Added a stat that counts the number of cancelled compactions.
Closes https://github.com/facebook/rocksdb/pull/3574
Differential Revision: D7190259
Pulled By: amytai
fbshipit-source-id: d5ce82dc9398da6d6d34023ad4ed8cec909852a3
Summary:
... so that people are not confused.
Closes https://github.com/facebook/rocksdb/pull/3580
Differential Revision: D7187175
Pulled By: sagar0
fbshipit-source-id: bce70093d52e38cd24c9432fd708885d7c2c013e
Summary:
This diff handles cases where compaction causes an ENOSPC error.
This does not handle corner cases where another background job is started while compaction is running, and the other background job triggers ENOSPC, although we do allow the user to provision for these background jobs with SstFileManager::SetCompactionBufferSize.
It also does not handle the case where compaction has finished and some other background job independently triggers ENOSPC.
Usage: Functionality is inside SstFileManager. In particular, users should set SstFileManager::SetMaxAllowedSpaceUsage, which is the reference highwatermark for determining whether to cancel compactions.
Closes https://github.com/facebook/rocksdb/pull/3449
Differential Revision: D7016941
Pulled By: amytai
fbshipit-source-id: 8965ab8dd8b00972e771637a41b4e6c645450445
Summary:
This patch addressed several issues.
Portability including db_test std::thread -> port::Thread Cc: @
and %z to ROCKSDB portable macro. Cc: maysamyabandeh
Implement Env::AreFilesSame
Make the implementation of file unique number more robust
Get rid of C-runtime and go directly to Windows API when dealing
with file primitives.
Implement GetSectorSize() and aling unbuffered read on the value if
available.
Adjust Windows Logger for the new interface, implement CloseImpl() Cc: anand1976
Fix test running script issue where $status var was of incorrect scope
so the failures were swallowed and not reported.
DestroyDB() creates a logger and opens a LOG file in the directory
being cleaned up. This holds a lock on the folder and the cleanup is
prevented. This fails one of the checkpoin tests. We observe the same in production.
We close the log file in this change.
Fix DBTest2.ReadAmpBitmapLiveInCacheAfterDBClose failure where the test
attempts to open a directory with NewRandomAccessFile which does not
work on Windows.
Fix DBTest.SoftLimit as it is dependent on thread timing. CC: yiwu-arbug
Closes https://github.com/facebook/rocksdb/pull/3552
Differential Revision: D7156304
Pulled By: siying
fbshipit-source-id: 43db0a757f1dfceffeb2b7988043156639173f5b
Summary:
Improving blob db FIFO eviction with the following changes,
* Change blob_dir_size to max_db_size. Take into account SST file size when computing DB size.
* FIFO now only take into account live sst files and live blob files. It is normal for disk usage to go over max_db_size because there are obsolete sst files and blob files pending deletion.
* FIFO eviction now also evict TTL blob files that's still open. It doesn't evict non-TTL blob files.
* If FIFO is triggered, it will pass an expiration and the current sequence number to compaction filter. Compaction filter will then filter inlined keys to evict those with an earlier expiration and smaller sequence number. So call LSM FIFO.
* Compaction filter also filter those blob indexes where corresponding blob file is gone.
* Add an event listener to listen compaction/flush event and update sst file size.
* Implement DB::Close() to make sure base db, as well as event listener and compaction filter, destruct before blob db.
* More blob db statistics around FIFO.
* Fix some locking issue when accessing a blob file.
Closes https://github.com/facebook/rocksdb/pull/3556
Differential Revision: D7139328
Pulled By: yiwu-arbug
fbshipit-source-id: ea5edb07b33dfceacb2682f4789bea61de28bbfa
Summary:
Fix the following bugs:
- During recovery a duplicate key was inserted twice into the write batch of the recovery transaction,
once when the memtable returns false (because it was duplicates) and once for the 2nd attempt. This would result into different SubBatch count measured when the recovered transactions is committing.
- If a cf is flushed during recovery the memtable is not available to assist in detecting the duplicate key. This could result into not advancing the sequence number when iterating over duplicate keys of a flushed cf and hence inserting the next key with the wrong sequence number.
- SubBacthCounter would reset the comparator to default comparator after the first duplicate key. The 2nd duplicate key hence would have gone through a wrong comparator and not being detected.
Closes https://github.com/facebook/rocksdb/pull/3562
Differential Revision: D7149440
Pulled By: maysamyabandeh
fbshipit-source-id: 91ec317b165f363f5d11ff8b8c47c81cebb8ed77
Summary:
Red diff to remove existing implementation of garbage collection. The current approach is reference counting kind of approach and require a lot of effort to get the size counter right on compaction and deletion. I'm going to go with a simple mark-sweep kind of approach and will send another PR for that.
CompactionEventListener was added solely for blob db and it adds complexity and overhead to compaction iterator. Removing it as well.
Closes https://github.com/facebook/rocksdb/pull/3551
Differential Revision: D7130190
Pulled By: yiwu-arbug
fbshipit-source-id: c3a375ad2639a3f6ed179df6eda602372cc5b8df
Summary:
Add "rocksdb.live-sst-files-size" DB property which only include files of latest version. Existing "rocksdb.total-sst-files-size" include files from all versions and thus include files that's obsolete but not yet deleted. I'm going to use this new property to cap blob db sst + blob files size.
Closes https://github.com/facebook/rocksdb/pull/3548
Differential Revision: D7116939
Pulled By: yiwu-arbug
fbshipit-source-id: c6a52e45ce0f24ef78708156e1a923c1dd6bc79a
Summary:
CompactRange has a call to Flush because we guarantee that, at the time it's called, all existing keys in the range will be pushed through the user's compaction filter. However, previously the flush was done blindly, so it'd happen even if the memtable does not contain keys in the range specified by the user. This caused unnecessarily many L0 files to be created, leading to write stalls in some cases. This PR checks the memtable's contents, and decides to flush only if it overlaps with `CompactRange`'s range.
- Move the memtable overlap check logic from `ExternalSstFileIngestionJob` to `ColumnFamilyData::RangesOverlapWithMemtables`
- Reuse the above logic in `CompactRange` and skip flushing if no overlap
Closes https://github.com/facebook/rocksdb/pull/3520
Differential Revision: D7018897
Pulled By: ajkr
fbshipit-source-id: a3c6b1cfae56687b49dd89ccac7c948e53545934
Summary:
The recent Logger::Close() and DBImpl::Close() implementation rely on
calling the CloseImpl() virtual function from the destructor, which will
not work. Refactor the implementation to have a private close helper
function in derived classes that can be called by both CloseImpl() and
the destructor.
Closes https://github.com/facebook/rocksdb/pull/3528
Reviewed By: gfosco
Differential Revision: D7049303
Pulled By: anand1976
fbshipit-source-id: 76a64cbf403209216dfe4864ecf96b5d7f3db9f4
Summary:
Make use of the index in WriteBatchWithIndex to also count the number of sub-batches. This eliminates the need to separately scan the batch to count the number of sub-batches once a duplicate key is detected.
Closes https://github.com/facebook/rocksdb/pull/3529
Differential Revision: D7049947
Pulled By: maysamyabandeh
fbshipit-source-id: 81cbf12c4e662541c772c7265a8f91631e25c7cd
Summary:
Added a new iterator property: `rocksdb.iterator.internal-key` to get the internal-key (converted to user key) at which the iterator stopped.
Closes https://github.com/facebook/rocksdb/pull/3525
Differential Revision: D7033694
Pulled By: sagar0
fbshipit-source-id: d51e6c00f5e9d766c6276ef79774b81c6c5216f8
Summary:
The MemTableRep API was broken by this commit: 813719e952
This patch reverts the changes and instead adds InsertKey (and etc.) overloads to extend the MemTableRep API without breaking the existing classes that inherit from it.
Closes https://github.com/facebook/rocksdb/pull/3513
Differential Revision: D7004134
Pulled By: maysamyabandeh
fbshipit-source-id: e568d91fe1e17dd76c0c1f6c7dd51a18633b1c4f
Summary:
TransactionDB::Write can receive some optimization hints from the user. One is to skip the concurrency control mechanism. WritePreparedTxnDB is currently ignoring such hints. This patch optimizes WritePreparedTxnDB::Write for skip_concurrency_control and skip_duplicate_key_check hints.
Closes https://github.com/facebook/rocksdb/pull/3496
Differential Revision: D6971784
Pulled By: maysamyabandeh
fbshipit-source-id: cbab10ad538fa2b8bcb47e37c77724afe6e30f03
Summary:
- Refactored logic for checking write stall condition to a helper function: `GetWriteStallConditionAndCause`. Now it is decoupled from the logic for updating WriteController / stats in `RecalculateWriteStallConditions`, so we can reuse it for predicting whether write stall will occur.
- Updated `CompactRange` to first check whether the one additional immutable memtable / L0 file would cause stalling before it flushes. If so, it waits until that is no longer true.
- Updated `bg_cv_` to be signaled on `SetOptions` calls. The stall conditions `CompactRange` cares about can change when (1) flush finishes, (2) compaction finishes, or (3) options dynamically change. The cv was already signaled for (1) and (2) but not yet for (3).
Closes https://github.com/facebook/rocksdb/pull/3381
Differential Revision: D6754983
Pulled By: ajkr
fbshipit-source-id: 5613e03f1524df7192dc6ae885d40fd8f091d972
Summary:
It's always a mystery from the logs why flush was triggered -- user triggered it manually, WriteBufferManager triggered it, logs were full, write buffer was full, etc.
This PR logs Flush reason whenever a flush is scheduled.
Closes https://github.com/facebook/rocksdb/pull/3401
Differential Revision: D6788142
Pulled By: miasantreble
fbshipit-source-id: a867e54d493c06adf5172bd36a180fb3faae3511
Summary:
Compared to DB::Write, TransactionDB::Write has the additional overhead of creating and initializing an internal transaction object, as well as the overhead of locking/unlocking the keys. This patch extends the TransactionDB::Write with an skip_cc option to allow the users to indicate that the write batch do not conflict with others and the concurrency control and its overhead can be skipped. TransactionDB::Write by default calls DB::Write when skip_cc is set, which works for WriteCommitted WritePolicy. Any other flavor of TransactionDB that is not compatible with this default behavior (such as WritePreparedTxnDB) can extend ::Write and implement their own approach for taking into account the skip_cc optimization.
Closes https://github.com/facebook/rocksdb/pull/3457
Differential Revision: D6877318
Pulled By: maysamyabandeh
fbshipit-source-id: 56f4e21db87ff71492db4e376fb7c2b03dfeab6b
Summary:
This patch takes advantage of memtable being able to detect duplicate <key,seq> and returning TryAgain to handle duplicate keys in WritePrepared Txns. Through WriteBatchWithIndex's index it detects existence of at least a duplicate key in the write batch. If duplicate key was reported, it then pays the cost of counting the number of sub-patches by iterating over the write batch and pass it to DBImpl::Write. DB will make use of the provided batch_count to assign proper sequence numbers before sending them to the WAL. When later inserting the batch to the memtable, it increases the seq each time memtbale reports a duplicate (a sub-patch in our counting) and tries again.
Closes https://github.com/facebook/rocksdb/pull/3455
Differential Revision: D6873699
Pulled By: maysamyabandeh
fbshipit-source-id: db8487526c3a5dc1ddda0ea49f0f979b26ae648d
