Summary:
Pointed out by https://github.com/facebook/rocksdb/issues/7197 , there is a double lock in WriteImplWALOnly.
Also find another deadlock in UnorderedWriteMemtable. Move the check after switch_all_.notify_all().
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7199
Test Plan: pass make check
Reviewed By: anand1976
Differential Revision: D22961714
Pulled By: zhichao-cao
fbshipit-source-id: 0707922dc50d28ea141a15a8cdcbd1c8993ea0d8
Summary:
In current codebase, in write path, if Retryable IO Error happens, SetBGError is called. The retryable IO Error is converted to hard error and DB is in read only mode. User or application needs to resume it. In this PR, if Retryable IO Error happens in one DB, SetBGError will create a new thread to call Resume (auto resume). otpions.max_bgerror_resume_count controls if auto resume is enabled or not (if max_bgerror_resume_count<=0, auto resume will not be enabled). options.bgerror_resume_retry_interval controls the time interval to call Resume again if the previous resume fails due to the Retryable IO Error. If non-retryable error happens during resume, auto resume will terminate.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6765
Test Plan: Added the unit test cases in error_handler_fs_test and pass make asan_check
Reviewed By: anand1976
Differential Revision: D21916789
Pulled By: zhichao-cao
fbshipit-source-id: acb8b5e5dc3167adfa9425a5b7fc104f6b95cb0b
Summary:
Preliminary user-timestamp support for delete.
If ["a", ts=100] exists, you can delete it by calling `DB::Delete(write_options, key)` in which `write_options.timestamp` points to a `ts` higher than 100.
Implementation
A new ValueType, i.e. `kTypeDeletionWithTimestamp` is added for deletion marker with timestamp.
The reason for a separate `kTypeDeletionWithTimestamp`: RocksDB may drop tombstones (keys with kTypeDeletion) when compacting them to the bottom level. This is OK and useful if timestamp is disabled. When timestamp is enabled, should we still reuse `kTypeDeletion`, we may drop the tombstone with a more recent timestamp, causing deleted keys to re-appear.
Test plan (dev server)
```
make check
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6253
Reviewed By: ltamasi
Differential Revision: D20995328
Pulled By: riversand963
fbshipit-source-id: a9e5c22968ad76f98e3dc6ee0151265a3f0df619
Summary:
In the current code base, we use Status to get and store the returned status from the call. Specifically, for IO related functions, the current Status cannot reflect the IO Error details such as error scope, error retryable attribute, and others. With the implementation of https://github.com/facebook/rocksdb/issues/5761, we have the new Wrapper for IO, which returns IOStatus instead of Status. However, the IOStatus is purged at the lower level of write path and transferred to Status.
The first job of this PR is to pass the IOStatus to the write path (flush, WAL write, and Compaction). The second job is to identify the Retryable IO Error as HardError, and set the bg_error_ as HardError. In this case, the DB Instance becomes read only. User is informed of the Status and need to take actions to deal with it (e.g., call db->Resume()).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6487
Test Plan: Added the testing case to error_handler_fs_test. Pass make asan_check
Reviewed By: anand1976
Differential Revision: D20685017
Pulled By: zhichao-cao
fbshipit-source-id: ff85f042896243abcd6ef37877834e26f36b6eb0
Summary:
In the current code base, we can use Directory from Env to manage directory (e.g, Fsync()). The PR https://github.com/facebook/rocksdb/issues/5761 introduce the File System as a new Env API. So we further replace the Directory class in DB with FSDirectory such that we can have more IO information from IOStatus returned by FSDirectory.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6468
Test Plan: pass make asan_check
Differential Revision: D20195261
Pulled By: zhichao-cao
fbshipit-source-id: 93962cb9436852bfcfb76e086d9e7babd461cbe1
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
Summary:
We were removing the file from `log_recycle_files_` before renaming it
with `ReuseWritableFile()`. Since `ReuseWritableFile()` occurs outside
the DB mutex, it was possible for a concurrent full purge to sneak in
and delete the file before it could be renamed. Consequently, `SwitchMemtable()`
would fail and the DB would enter read-only mode.
The fix is to hold the old file number in `log_recycle_files_` until
after the file has been renamed. Full purge uses that list to decide
which files to keep, so it can no longer delete a file pending recycling.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5900
Test Plan: new unit test
Differential Revision: D19771719
Pulled By: ajkr
fbshipit-source-id: 094346349ca3fb499712e62de03905acc30b5ce8
Summary:
When `no_slowdown` is enabled, it returns `Status::Incomplete("Write stall")` if a stall would occur. This patch adds descriptive text for when `no_slowdown` and `low_pri` are enabled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6396
Differential Revision: D19808978
Pulled By: cheng-chang
fbshipit-source-id: a53b0d25ed414c821a086531e0222027f925e627
Summary:
It chooses the oldest memtable, not the largest one. This is an
important difference for users whose CFs receive non-uniform write
rates.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6335
Differential Revision: D19588865
Pulled By: maysamyabandeh
fbshipit-source-id: 62ad4325b0182f5f27858584cd73fd5978fb2cec
Summary:
We have observed an increase in CPU load caused by frequent calls to
`ColumnFamilyData::InstallSuperVersion` from `DBImpl::TrimMemtableHistory`
when using `max_write_buffer_size_to_maintain` to limit the amount of
memtable history maintained for transaction conflict checking. As it turns out,
this is caused by the code creating and installing a new `SuperVersion` even if
no memtables were actually trimmed. The patch adds a check to avoid this.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6169
Test Plan:
Compared `perf` output for
```
./db_bench -benchmarks=randomtransaction -optimistic_transaction_db=1 -statistics -stats_interval_seconds=1 -duration=90 -num=500000 --max_write_buffer_size_to_maintain=16000000 --transaction_set_snapshot=1 --threads=32
```
before and after the change. With the fix, the call chain `rocksdb::DBImpl::TrimMemtableHistory` ->
`rocksdb::ColumnFamilyData::InstallSuperVersion` -> `rocksdb::ThreadLocalPtr::StaticMeta::Scrape`
no longer registers in the `perf` report.
Differential Revision: D19031509
Pulled By: ltamasi
fbshipit-source-id: 02686fce594e5b50eba0710e4b28a9b808c8aa20
Summary:
It's easy to cause coredump when closing ColumnFamilyHandle with unreleased iterators, especially iterators release is controlled by java GC when using JNI.
This patch fixed concurrent CF iteration and drop, we let iterators(actually SuperVersion) hold a ColumnFamilyData reference to prevent the CF from being released too early.
fixed https://github.com/facebook/rocksdb/issues/5982
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6147
Differential Revision: D18926378
fbshipit-source-id: 1dff6d068c603d012b81446812368bfee95a5e15
Summary:
**Summary:**
This PR fixes two unordered_write related issues:
- ingestion job may skip the necessary memtable flush https://github.com/facebook/rocksdb/issues/6026
- compact range may cause memtable is flushed before pending unordered write finished
1. `CompactRange` triggers memtable flush but doesn't wait for pending-writes
2. there are some pending writes but memtable is already flushed
3. the memtable related WAL is removed( note that the pending-writes were recorded in that WAL).
4. pending-writes write to newer created memtable
5. there is a restart
6. missing the previous pending-writes because WAL is removed but they aren't included in SST.
**How to solve:**
- Wait pending memtable writes before ingestion job check memtable key range
- Wait pending memtable writes before flush memtable.
**Note that: `CompactRange` calls `RangesOverlapWithMemtables` too without waiting for pending waits, but I'm not sure whether it affects the correctness.**
**Test Plan:**
make check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6113
Differential Revision: D18895674
Pulled By: maysamyabandeh
fbshipit-source-id: da22b4476fc7e06c176020e7cc171eb78189ecaf
Summary:
When two_write_queue enable, IngestExternalFile performs EnterUnbatched on both write queues. SwitchMemtable also EnterUnbatched on 2nd write queue when this option is enabled. When the call stack includes IngestExternalFile -> FlushMemTable -> SwitchMemtable, this results into a deadlock.
The implemented solution is to pass on the existing writes_stopped argument in FlushMemTable to skip EnterUnbatched in SwitchMemtable.
Fixes https://github.com/facebook/rocksdb/issues/5974
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5976
Differential Revision: D18535943
Pulled By: maysamyabandeh
fbshipit-source-id: a4f9d4964c10d4a7ca06b1e0102ca2ec395512bc
Summary:
In pipeline writing mode, memtable switching needs to wait for memtable writing to finish to make sure that when memtables are made immutable, inserts are not going to them. This is currently done in DBImpl::SwitchMemtable(). This is done after flush_scheduler_.TakeNextColumnFamily() is called to fetch the list of column families to switch. The function flush_scheduler_.TakeNextColumnFamily() itself, however, is not thread-safe when being called together with flush_scheduler_.ScheduleFlush().
This change provides a fix, which moves the waiting logic before flush_scheduler_.TakeNextColumnFamily(). WaitForPendingWrites() is a natural place where the logic can happen.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5716
Test Plan: Run all tests with ASAN and TSAN.
Differential Revision: D18217658
fbshipit-source-id: b9c5e765c9989645bf10afda7c5c726c3f82f6c3
Summary:
When building with clang 9, warning is reported for InternalDBStatsType type names shadowed the one for statistics. Rename them.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5779
Test Plan: Build with clang 9 and see it passes.
Differential Revision: D17239378
fbshipit-source-id: af28fb42066c738cd1b841f9fe21ab4671dafd18
Summary:
MyRocks currently sets `max_write_buffer_number_to_maintain` in order to maintain enough history for transaction conflict checking. The effectiveness of this approach depends on the size of memtables. When memtables are small, it may not keep enough history; when memtables are large, this may consume too much memory.
We are proposing a new way to configure memtable list history: by limiting the memory usage of immutable memtables. The new option is `max_write_buffer_size_to_maintain` and it will take precedence over the old `max_write_buffer_number_to_maintain` if they are both set to non-zero values. The new option accounts for the total memory usage of flushed immutable memtables and mutable memtable. When the total usage exceeds the limit, RocksDB may start dropping immutable memtables (which is also called trimming history), starting from the oldest one.
The semantics of the old option actually works both as an upper bound and lower bound. History trimming will start if number of immutable memtables exceeds the limit, but it will never go below (limit-1) due to history trimming.
In order the mimic the behavior with the new option, history trimming will stop if dropping the next immutable memtable causes the total memory usage go below the size limit. For example, assuming the size limit is set to 64MB, and there are 3 immutable memtables with sizes of 20, 30, 30. Although the total memory usage is 80MB > 64MB, dropping the oldest memtable will reduce the memory usage to 60MB < 64MB, so in this case no memtable will be dropped.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5022
Differential Revision: D14394062
Pulled By: miasantreble
fbshipit-source-id: 60457a509c6af89d0993f988c9b5c2aa9e45f5c5
Summary:
In previous https://github.com/facebook/rocksdb/issues/5079, we added user-specified timestamp to `DB::Get()` and `DB::Put()`. Limitation is that these two functions may cause extra memory allocation and key copy. The reason is that `WriteBatch` does not allocate extra memory for timestamps because it is not aware of timestamp size, and we did not provide an API to assign/update timestamp of each key within a `WriteBatch`.
We address these issues in this PR by doing the following.
1. Add a `timestamp_size_` to `WriteBatch` so that `WriteBatch` can take timestamps into account when calling `WriteBatch::Put`, `WriteBatch::Delete`, etc.
2. Add APIs `WriteBatch::AssignTimestamp` and `WriteBatch::AssignTimestamps` so that application can assign/update timestamps for each key in a `WriteBatch`.
3. Avoid key copy in `GetImpl` by adding new constructor to `LookupKey`.
Test plan (on devserver):
```
$make clean && COMPILE_WITH_ASAN=1 make -j32 all
$./db_basic_test --gtest_filter=Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/*
$make check
```
If the API extension looks good, I will add more unit tests.
Some simple benchmark using db_bench.
```
$rm -rf /dev/shm/dbbench/* && TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillseq,readrandom -num=1000000
$rm -rf /dev/shm/dbbench/* && TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=1000000 -disable_wal=true
```
Master is at a78503bd6c.
```
| | readrandom | fillrandom |
| master | 15.53 MB/s | 25.97 MB/s |
| PR5502 | 16.70 MB/s | 25.80 MB/s |
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5502
Differential Revision: D16340894
Pulled By: riversand963
fbshipit-source-id: 51132cf792be07d1efc3ac33f5768c4ee2608bb8
Summary:
There are a number of fixes in this PR (with most bugs found via the added stress tests):
1. Re-enable reseek optimization. This was initially disabled to avoid infinite loops in https://github.com/facebook/rocksdb/pull/3955 but this can be resolved by remembering not to reseek after a reseek has already been done. This problem only affects forward iteration in `DBIter::FindNextUserEntryInternal`, as we already disable reseeking in `DBIter::FindValueForCurrentKeyUsingSeek`.
2. Verify that ReadOption.snapshot can be safely used for iterator creation. Some snapshots would not give correct results because snaphsot validation would not be enforced, breaking some assumptions in Prev() iteration.
3. In the non-snapshot Get() case, reads done at `LastPublishedSequence` may not be enough, because unprepared sequence numbers are not published. Use `std::max(published_seq, max_visible_seq)` to do lookups instead.
4. Add stress test to test reading own writes.
5. Minor bug in the allow_concurrent_memtable_write case where we forgot to pass in batch_per_txn_.
6. Minor performance optimization in `CalcMaxUnpreparedSequenceNumber` by assigning by reference instead of value.
7. Add some more comments everywhere.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5573
Differential Revision: D16276089
Pulled By: lth
fbshipit-source-id: 18029c944eb427a90a87dee76ac1b23f37ec1ccb
Summary:
WAL records RocksDB writes to all column families. When user flushes a a column family, the old WAL will not accept new writes but cannot be deleted yet because it may still contain live data for other column families. (See https://github.com/facebook/rocksdb/wiki/Write-Ahead-Log#life-cycle-of-a-wal for detailed explanation)
Because of this, if there is a column family that receive very infrequent writes and no manual flush is called for it, it could prevent a lot of WALs from being deleted. PR https://github.com/facebook/rocksdb/pull/5046 introduced persistent stats column family which is a good example of such column families. Depending on the config, it may have long intervals between writes, and user is unaware of it which makes it difficult to call manual flush for it.
This PR addresses the problem for persistent stats column family by forcing a flush for persistent stats column family when 1) another column family is flushed 2) persistent stats column family's log number is the smallest among all column families, this way persistent stats column family will keep advancing its log number when necessary, allowing RocksDB to delete old WAL files.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5509
Differential Revision: D16045896
Pulled By: miasantreble
fbshipit-source-id: 286837b633e988417f0096ff38384742d3b40ef4
Summary:
The patch reduces the contention over prepared_mutex_ using these techniques:
1) Move ::RemovePrepared() to be called from the commit callback when we have two write queues.
2) Use two separate mutex for PreparedHeap, one prepared_mutex_ needed for ::RemovePrepared, and one ::push_pop_mutex() needed for ::AddPrepared(). Given that we call ::AddPrepared only from the first write queue and ::RemovePrepared mostly from the 2nd, this will result into each the two write queues not competing with each other over a single mutex. ::RemovePrepared might occasionally need to acquire ::push_pop_mutex() if ::erase() ends up with calling ::pop()
3) Acquire ::push_pop_mutex() on the first callback of the write queue and release it on the last.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5420
Differential Revision: D15741985
Pulled By: maysamyabandeh
fbshipit-source-id: 84ce8016007e88bb6e10da5760ba1f0d26347735
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402
Differential Revision: D15701195
Pulled By: miasantreble
fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
Summary:
It's useful to be able to (optionally) associate key-value pairs with user-provided timestamps. This PR is an early effort towards this goal and continues the work of facebook#4942. A suite of new unit tests exist in DBBasicTestWithTimestampWithParam. Support for timestamp requires the user to provide timestamp as a slice in `ReadOptions` and `WriteOptions`. All timestamps of the same database must share the same length, format, etc. The format of the timestamp is the same throughout the same database, and the user is responsible for providing a comparator function (Comparator) to order the <key, timestamp> tuples. Once created, the format and length of the timestamp cannot change (at least for now).
Test plan (on devserver):
```
$COMPILE_WITH_ASAN=1 make -j32 all
$./db_basic_test --gtest_filter=Timestamp/DBBasicTestWithTimestampWithParam.PutAndGet/*
$make check
```
All tests must pass.
We also run the following db_bench tests to verify whether there is regression on Get/Put while timestamp is not enabled.
```
$TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillseq,readrandom -num=1000000
$TEST_TMPDIR=/dev/shm ./db_bench -benchmarks=fillrandom -num=1000000
```
Repeat for 6 times for both versions.
Results are as follows:
```
| | readrandom | fillrandom |
| master | 16.77 MB/s | 47.05 MB/s |
| PR5079 | 16.44 MB/s | 47.03 MB/s |
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5079
Differential Revision: D15132946
Pulled By: riversand963
fbshipit-source-id: 833a0d657eac21182f0f206c910a6438154c742c
Summary:
There are too many types of files under util/. Some test related files don't belong to there or just are just loosely related. Mo
ve them to a new directory test_util/, so that util/ is cleaner.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5377
Differential Revision: D15551366
Pulled By: siying
fbshipit-source-id: 0f5c8653832354ef8caa31749c0143815d719e2c
Summary:
WritePrepared transactions when configured with two_write_queues=true offers higher throughput with unordered_write feature without however compromising the rocksdb guarantees. This is because it performs ordering among writes in a 2nd step that is not tied to memtable write speed. The 2nd step is naturally provided by 2PC when the commit phase does the ordering as well. Without 2PC, the 2nd step would only be provided when we use two_write_queues=true, where WritePrepared after performing the writes, in a 2nd step uses the 2nd queue to assign order to the writes.
The patch clarifies the need for two_write_queues=true in the HISTORY and inline comments of unordered_writes. Moreover it extends the stress tests of WritePrepared to unordred_write.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5313
Differential Revision: D15379977
Pulled By: maysamyabandeh
fbshipit-source-id: 5b6f05b9b59285dcbf3b0532215ba9fe7d926e00
Summary:
The recent improvement in https://github.com/facebook/rocksdb/pull/3661 could cause a deadlock: When writing recoverable state, we also commit its sequence number to commit table, which could result into evicting existing commit entry, which could result into advancing max_evicted_seq_, which would need to get snapshots from database, which requires obtaining db mutex. The patch releases db_mutex before calling the callback in WriteRecoverableState to avoid the potential deadlock. It also improves the stress tests to let the issue be manifested in the tests.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5306
Differential Revision: D15341458
Pulled By: maysamyabandeh
fbshipit-source-id: 05dcbed7e21b789fd1e5fd5ee8eea08077162323
Summary:
Performing unordered writes in rocksdb when unordered_write option is set to true. When enabled the writes to memtable are done without joining any write thread. This offers much higher write throughput since the upcoming writes would not have to wait for the slowest memtable write to finish. The tradeoff is that the writes visible to a snapshot might change over time. If the application cannot tolerate that, it should implement its own mechanisms to work around that. Using TransactionDB with WRITE_PREPARED write policy is one way to achieve that. Doing so increases the max throughput by 2.2x without however compromising the snapshot guarantees.
The patch is prepared based on an original by siying
Existing unit tests are extended to include unordered_write option.
Benchmark Results:
```
TEST_TMPDIR=/dev/shm/ ./db_bench_unordered --benchmarks=fillrandom --threads=32 --num=10000000 -max_write_buffer_number=16 --max_background_jobs=64 --batch_size=8 --writes=3000000 -level0_file_num_compaction_trigger=99999 --level0_slowdown_writes_trigger=99999 --level0_stop_writes_trigger=99999 -enable_pipelined_write=false -disable_auto_compactions --unordered_write=1
```
With WAL
- Vanilla RocksDB: 78.6 MB/s
- WRITER_PREPARED with unordered_write: 177.8 MB/s (2.2x)
- unordered_write: 368.9 MB/s (4.7x with relaxed snapshot guarantees)
Without WAL
- Vanilla RocksDB: 111.3 MB/s
- WRITER_PREPARED with unordered_write: 259.3 MB/s MB/s (2.3x)
- unordered_write: 645.6 MB/s (5.8x with relaxed snapshot guarantees)
- WRITER_PREPARED with unordered_write disable concurrency control: 185.3 MB/s MB/s (2.35x)
Limitations:
- The feature is not yet extended to `max_successive_merges` > 0. The feature is also incompatible with `enable_pipelined_write` = true as well as with `allow_concurrent_memtable_write` = false.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5218
Differential Revision: D15219029
Pulled By: maysamyabandeh
fbshipit-source-id: 38f2abc4af8780148c6128acdba2b3227bc81759
Summary:
Right now, two separate pieces of code are used to create WAL files in DBImpl::Open function of db_impl_open.cc and DBImpl::SwitchMemtable function of db_impl_write.cc. This code change simply creates 1 function called DBImpl::CreateWAL in db_impl_open.cc which is used to replace existing WAL creation logic in DBImpl::Open and DBImpl::SwitchMemtable.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5188
Differential Revision: D14942832
Pulled By: vjnadimpalli
fbshipit-source-id: d49230e04c36176015c8c1b422575872f92157fb
Summary:
Annotate all of the logging functions to inform the compiler that these
use printf-style formatting arguments. This allows the compiler to emit
warnings if the format arguments are incorrect.
This also fixes many problems reported now that format string checking
is enabled. Many of these are simply mix-ups in the argument type (e.g,
int vs uint64_t), but in several cases the wrong number of arguments
were being passed in which can cause the code to crash.
The primary motivation for this was to fix the log message in
`DBImpl::SwitchMemtable()` which caused a segfault due to an extra %s
format parameter with no argument supplied.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5089
Differential Revision: D14574795
Pulled By: simpkins
fbshipit-source-id: 0921b03f0743652bf4ae21e414ff54b3bb65422a
Summary:
In prepare phase of 2PC, the db promises to remember the prepared data, for possible future commits. To fulfill the promise the prepared data must be persisted in the WAL so that they could be recovered after a crash. The log that contains a prepare batch that is not committed yet, is marked so that it is not garbage collected before the transaction commits/rollbacks. The bug was that the write to the log file and the mark of the file was not atomic, and WAL gc could have happened before the WAL log is actually marked. This patch moves the marking logic to PreReleaseCallback so that the WAL gc logic that joins both write threads would see the WAL write and WAL mark atomically.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5121
Differential Revision: D14665210
Pulled By: maysamyabandeh
fbshipit-source-id: 1d66aeb1c66a296cb4899a5a20c4d40c59e4b534
Summary:
Following files were run through automatic formatter:
db/db_impl.cc
db/db_impl.h
db/db_impl_compaction_flush.cc
db/db_impl_debug.cc
db/db_impl_files.cc
db/db_impl_readonly.h
db/db_impl_write.cc
db/dbformat.cc
db/dbformat.h
table/block.cc
table/block.h
table/block_based_filter_block.cc
table/block_based_filter_block.h
table/block_based_filter_block_test.cc
table/block_based_table_builder.cc
table/block_based_table_reader.cc
table/block_based_table_reader.h
table/block_builder.cc
table/block_builder.h
table/block_fetcher.cc
table/block_prefix_index.cc
table/block_prefix_index.h
table/block_test.cc
table/format.cc
table/format.h
I could easily run all the files, but I don't want people to feel that
I'm doing it for lines of code changes :)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5114
Differential Revision: D14633040
Pulled By: siying
fbshipit-source-id: 3f346cb53bf21e8c10704400da548dfce1e89a52
Summary:
There is a potential failure case in DBImpl::SwitchMemtable() that is not handled properly. The call to cur_log_writer->WriteBuffer() can fail due to an IO error. In that case, we need to call SetBGError() in order set the background error since the WriteBuffer() failure may result in data loss.
Also, the asserts for !new_mem and !new_log are incorrect, as those would have been allocated by the time this failure is detected.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5072
Differential Revision: D14461384
Pulled By: anand1976
fbshipit-source-id: fb59bce9d61378f37d2dfcd28c0b704b0f43c3cf
Summary:
PreReleaseCallback meant to be called before the writes are visible to the readers. Since the sequence number is known after the WAL write, there is no reason to delay calling PreReleaseCallback to after the memtable write, which would complicates the reader's logic in presence of our memtable writes that are made visible by the other write thread.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5015
Differential Revision: D14221670
Pulled By: maysamyabandeh
fbshipit-source-id: a504dd665cf923226d7af09cc8e9c7739a25edc6
Summary:
Statistics cost too much CPU for some use cases. Add two stats levels
so that people can choose to skip two types of expensive stats, timers and
histograms.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5027
Differential Revision: D14252765
Pulled By: siying
fbshipit-source-id: 75ecec9eaa44c06118229df4f80c366115346592
Summary:
Measure CPU time consumed for a compaction and report it in the stats report
Enable NowCPUNanos() to work for MacOS
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4889
Differential Revision: D13701276
Pulled By: zinoale
fbshipit-source-id: 5024e5bbccd4dd10fd90d947870237f436445055
Summary:
The original implementation has two problems:
1. f0dda35d7d/db/db_impl_write.cc (L478)f0dda35d7d/db/write_thread.h (L231)
If the callback status of leader of the write_group fails, then the whole write_group will not write to WAL, this may cause data loss.
2. f0dda35d7d/db/write_thread.h (L130)
The annotation says that Writer.status is the status of memtable inserter, but the original implementation use it for another case which is not consistent with the original design. Looks like we can still reuse Writer.status, but we should modify the annotation, so Writer.status is not only the status of memtable inserter.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4838
Differential Revision: D13574070
Pulled By: yiwu-arbug
fbshipit-source-id: a2a2aefcfd329c4c6a91652bf090aaf1ce119c4b
Summary:
In the past, both `DBImpl::atomic_flush_` and
`DBImpl::immutable_db_options_.atomic_flush` exist. However, we fail to set
`immutable_db_options_.atomic_flush`, but use `DBImpl::atomic_flush_` which is
set correctly. This does not lead to incorrect behavior, but is a duplicate of
information.
Since `immutable_db_options_` is always there and has `atomic_flush`, we should
use it as source of truth and remove `DBImpl::atomic_flush_`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4631
Differential Revision: D12928371
Pulled By: riversand963
fbshipit-source-id: f85a811959d3828aad4a3a1b05f71facf19c636d
Summary:
Ran the following commands to recursively change all the files under RocksDB:
```
find . -type f -name "*.cc" -exec sed -i 's/ unique_ptr/ std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<unique_ptr/<std::unique_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/ shared_ptr/ std::shared_ptr/g' {} +
find . -type f -name "*.cc" -exec sed -i 's/<shared_ptr/<std::shared_ptr/g' {} +
```
Running `make format` updated some formatting on the files touched.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4638
Differential Revision: D12934992
Pulled By: sagar0
fbshipit-source-id: 45a15d23c230cdd64c08f9c0243e5183934338a8
Summary:
For flush triggered by RocksDB due to memory usage approaching certain
threshold (WriteBufferManager or Memtable full), we should cut the memtable
only when the current active memtable is not empty, i.e. contains data. This is
what we do for non-atomic flush. If we always cut memtable even when the active
memtable is empty, we will generate extra, empty immutable memtable.
This is not ideal since it may cause write stall. It also causes some
DBAtomicFlushTest to fail because cfd->imm()->NumNotFlushed() is different from
expectation.
Test plan
```
$make clean && make J=1 -j32 all check
$make clean && OPT="-DROCKSDB_LITE -g" make J=1 -j32 all check
$make clean && TEST_TMPDIR=/dev/shm/rocksdb OPT=-g make J=1 -j32 valgrind_test
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4595
Differential Revision: D12818520
Pulled By: riversand963
fbshipit-source-id: d867bdbeacf4199fdd642debb085f94703c41a18
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:
There is a bug when the write queue leader is blocked on a write
delay/stop, and the queue has writers with WriteOptions::no_slowdown set
to true. They are not woken up until the write stall is cleared.
The fix introduces a dummy writer inserted at the tail to indicate a
write stall and prevent further inserts into the queue, and a condition
variable that writers who can tolerate slowdown wait on before adding
themselves to the queue. The leader calls WriteThread::BeginWriteStall()
to add the dummy writer and then walk the queue to fail any writers with
no_slowdown set. Once the stall clears, the leader calls
WriteThread::EndWriteStall() to remove the dummy writer and signal the
condition variable.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4475
Differential Revision: D10285827
Pulled By: anand1976
fbshipit-source-id: 747465e5e7f07a829b1fb0bc1afcd7b93f4ab1a9
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:
RocksDB currently queues individual column family for flushing. This is not sufficient to support the needs of some applications that want to enforce order/dependency between column families, given that multiple foreground and background activities can trigger flushing in RocksDB.
This PR aims to address this limitation. Each flush request is described as a `FlushRequest` that can contain multiple column families. A background flushing thread pops one flush request from the queue at a time and processes it.
This PR does not enable atomic_flush yet, but is a subset of [PR 3752](https://github.com/facebook/rocksdb/pull/3752).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/3952
Differential Revision: D8529933
Pulled By: riversand963
fbshipit-source-id: 78908a21e389a3a3f7de2a79bae0cd13af5f3539
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
Zhichao Cao