Summary:
Make `DB::GetUpdatesSince` return early if told to scan WALs generated by transactions
with write-prepared or write-unprepared policies (`seq_per_batch` is true), as indicated by
API comment.
Also add checks to `TransactionLogIterator` to clarify some conditions.
No API change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9459
Test Plan:
make check
Closing https://github.com/facebook/rocksdb/issues/1565
Reviewed By: akankshamahajan15
Differential Revision: D33821243
Pulled By: riversand963
fbshipit-source-id: c8b155d020ce0980e2d3b3b1da40b96e65b48d79
Summary:
**This PR does not affect the functionality of `DB` and write-committed transactions.**
`CompactionIterator` uses `KeyCommitted(seq)` to determine if a key in the database is committed.
As the name 'write-committed' implies, if write-committed policy is used, a key exists in the database only if
it is committed. In fact, the implementation of `KeyCommitted()` is as follows:
```
inline bool KeyCommitted(SequenceNumber seq) {
// For non-txn-db and write-committed, snapshot_checker_ is always nullptr.
return snapshot_checker_ == nullptr ||
snapshot_checker_->CheckInSnapshot(seq, kMaxSequence) == SnapshotCheckerResult::kInSnapshot;
}
```
With that being said, we focus on write-prepared/write-unprepared transactions.
A few notes:
- A key can exist in the db even if it's uncommitted. Therefore, we rely on `snapshot_checker_` to determine data visibility. We also require that all writes go through transaction API instead of the raw `WriteBatch` + `Write`, thus at most one uncommitted version of one user key can exist in the database.
- `CompactionIterator` outputs a key as long as the key is uncommitted.
Due to the above reasons, it is possible that `CompactionIterator` decides to output an uncommitted key without
doing further checks on the key (`NextFromInput()`). By the time the key is being prepared for output, the key becomes
committed because the `snapshot_checker_(seq, kMaxSequence)` becomes true in the implementation of `KeyCommitted()`.
Then `CompactionIterator` will try to zero its sequence number and hit assertion error if the key is a tombstone.
To fix this issue, we should make the `CompactionIterator` see a consistent view of the input keys. Note that
for write-prepared/write-unprepared, the background flush/compaction jobs already take a "job snapshot" before starting
processing keys. The job snapshot is released only after the entire flush/compaction finishes. We can use this snapshot
to determine whether a key is committed or not with minor change to `KeyCommitted()`.
```
inline bool KeyCommitted(SequenceNumber sequence) {
// For non-txn-db and write-committed, snapshot_checker_ is always nullptr.
return snapshot_checker_ == nullptr ||
snapshot_checker_->CheckInSnapshot(sequence, job_snapshot_) ==
SnapshotCheckerResult::kInSnapshot;
}
```
As a result, whether a key is committed or not will remain a constant throughout compaction, causing no trouble
for `CompactionIterator`s assertions.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9830
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D35561162
Pulled By: riversand963
fbshipit-source-id: 0e00d200c195240341cfe6d34cbc86798b315b9f
Summary:
This gives users the ability to examine the map populated by `GetMapProperty()` with property `kBlockCacheEntryStats`. It also sets us up for a possible future where cache reservations are configured according to `CacheEntryRole`s rather than flags coupled to roles.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9838
Test Plan:
- migrated test DBBlockCacheTest.CacheEntryRoleStats to use this API. That test verifies some of the contents are as expected
- added a DBPropertiesTest to verify the public map keys are present, and nothing else
Reviewed By: hx235
Differential Revision: D35629493
Pulled By: ajkr
fbshipit-source-id: 5c4356b8560e85d1f881fd32c44c15960b02fc68
Summary:
This information has been already available as part of the `rocksdb.blob-stats`
string property. The patch adds a dedicated integer property to make it easier
to surface this information in monitoring systems.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9835
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D35619495
Pulled By: ltamasi
fbshipit-source-id: 03fb0b228aa27d3859a1e3783bcb7eca095607f8
Summary:
Add the ability to cancel remote compaction on the remote side by
setting `OpenAndCompactOptions.canceled` to true.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9725
Test Plan: added unittest
Reviewed By: ajkr
Differential Revision: D35018800
Pulled By: jay-zhuang
fbshipit-source-id: be3652f9645e0347df429e42a5614d5a9b3a1ec4
Summary:
Especially after updating to C++17, I don't see a compelling case for
*requiring* any folly components in RocksDB. I was able to purge the existing
hard dependencies, and it can be quite difficult to strip out non-trivial components
from folly for use in RocksDB. (The prospect of doing that on F14 has changed
my mind on the best approach here.)
But this change creates an optional integration where we can plug in
components from folly at compile time, starting here with F14FastMap to replace
std::unordered_map when possible (probably no public APIs for example). I have
replaced the biggest CPU users of std::unordered_map with compile-time
pluggable UnorderedMap which will use F14FastMap when USE_FOLLY is set.
USE_FOLLY is always set in the Meta-internal buck build, and a simulation of
that is in the Makefile for public CI testing. A full folly build is not needed, but
checking out the full folly repo is much simpler for getting the dependency,
and anything else we might want to optionally integrate in the future.
Some picky details:
* I don't think the distributed mutex stuff is actually used, so it was easy to remove.
* I implemented an alternative to `folly::constexpr_log2` (which is much easier
in C++17 than C++11) so that I could pull out the hard dependencies on
`ConstexprMath.h`
* I had to add noexcept move constructors/operators to some types to make
F14's complainUnlessNothrowMoveAndDestroy check happy, and I added a
macro to make that easier in some common cases.
* Updated Meta-internal buck build to use folly F14Map (always)
No updates to HISTORY.md nor INSTALL.md as this is not (yet?) considered a
production integration for open source users.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9546
Test Plan:
CircleCI tests updated so that a couple of them use folly.
Most internal unit & stress/crash tests updated to use Meta-internal latest folly.
(Note: they should probably use buck but they currently use Makefile.)
Example performance improvement: when filter partitions are pinned in cache,
they are tracked by PartitionedFilterBlockReader::filter_map_ and we can build
a test that exercises that heavily. Build DB with
```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=30000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters
```
and test with (simultaneous runs with & without folly, ~20 times each to see
convergence)
```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench_folly -readonly -use_existing_db -benchmarks=readrandom -num=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters -duration=40 -pin_l0_filter_and_index_blocks_in_cache
```
Average ops/s no folly: 26229.2
Average ops/s with folly: 26853.3 (+2.4%)
Reviewed By: ajkr
Differential Revision: D34181736
Pulled By: pdillinger
fbshipit-source-id: ffa6ad5104c2880321d8a1aa7187e00ab0d02e94
Summary:
So the user is able to set event listener on the compactor
side.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9821
Test Plan: unittest added
Reviewed By: ajkr
Differential Revision: D35485388
Pulled By: jay-zhuang
fbshipit-source-id: 669d8a3aaee012b75b940470306756c03ffa09b2
Summary:
1) In case of non-TransactionDB and avoid_flush_during_recovery = true, RocksDB won't
flush the data from WAL to L0 for all column families if possible. As a
result, not all column families can increase their log_numbers, and
min_log_number_to_keep won't change.
2) For transaction DB (.allow_2pc), even with the flush, there may be old WAL files that it must not delete because they can contain data of uncommitted transactions and min_log_number_to_keep won't change.
If we persist a new MANIFEST with
advanced log_numbers for some column families, then during a second
crash after persisting the MANIFEST, RocksDB will see some column
families' log_numbers larger than the corrupted wal, and the "column family inconsistency" error will be hit, causing recovery to fail.
As a solution,
1. the corrupted WALs whose numbers are larger than the
corrupted wal and smaller than the new WAL will be moved to archive folder.
2. Currently, RocksDB DB::Open() may creates and writes to two new MANIFEST files even before recovery succeeds. This PR buffers the edits in a structure and writes to a new MANIFEST after recovery is successful
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9634
Test Plan:
1. Added new unit tests
2. make crast_test -j
Reviewed By: riversand963
Differential Revision: D34463666
Pulled By: akankshamahajan15
fbshipit-source-id: e233d3af0ed4e2028ca0cf051e5a334a0fdc9d19
Summary:
Options `preserve_deletes` and `iter_start_seqnum` have been removed since 7.0.
This PR removes dead code related to these two removed options.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9825
Test Plan: make check
Reviewed By: akankshamahajan15
Differential Revision: D35517950
Pulled By: riversand963
fbshipit-source-id: 86282ce5ec4087acb94a06a42a1b6d55b1715482
Summary:
When sub compaction is decided for L0->L1 compaction, most of the cases, all L0 files will be involved in all sub compactions. However, it is not always the case. When files are generally (but not strictly) inserted in sequential order, there can be a subset of L0 files invovled. Yet RocksDB always open all those L0 files, and build an iterator, read many of the files' first of last block with expensive readahead. We trim some input files to reduce overhead a little bit.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9802
Test Plan: Add a unit test to cover this case and manually validate the behavior while running the test.
Reviewed By: ajkr
Differential Revision: D35371031
fbshipit-source-id: 701ed7375b5cbe41672e93b38fe8a1503dad08b6
Summary:
This change adds two unit tests that would each catch the
regression fixed in https://github.com/facebook/rocksdb/issues/9736
* TableMetaIndexKeys - detects any churn in metaindex block keys
generated by SST files using standard db_test_util configurations.
* BloomFilterCompatibility - this detects if any common built-in
FilterPolicy configurations fail to read filters generated by another.
(The regression bug caused NewRibbonFilterPolicy not to read filters
from NewBloomFilterPolicy and vice-versa.) This replaces some previous
tests that didn't really appear to be testing much of anything except
basic data correctness, which doesn't tell you a filter is being used.
Light refactoring in meta_blocks.cc/h to support inspecting metaindex
keys.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9773
Test Plan:
this is the test. Verified that 7.0.2 fails both tests and 7.0.3 passes.
With backporting for intentional API changes in 7.0, 6.29 also passes.
Reviewed By: ajkr
Differential Revision: D35236248
Pulled By: pdillinger
fbshipit-source-id: 493dfe9ad7e27524bf7c6c1af8a4b8c31bc6ef5a
Summary:
For write-prepared/write-unprepared transactions,
GetCommitTimeWriteBatch() can be used only if the transaction is started
with `TransactionOptions::use_only_the_last_commit_time_batch_for_recovery` set
to true. Otherwise, it is possible that multiple uncommitted versions of the
same key exist in the database. During bottommost compaction, RocksDB may
set the sequence numbers of both to zero once they become committed, causing
output SST file to have two identical internal keys.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9794
Test Plan:
make check
pay special attention to the following
```
transaction_test --gtest_filter=MySQLStyleTransactionTest/MySQLStyleTransactionTest.TransactionStressTest/*
```
Reviewed By: lth
Differential Revision: D35327214
Pulled By: riversand963
fbshipit-source-id: 3bae00a28359c10e96e4c6f676d20de5610d8a0f
Summary:
Various renaming and fixes to get rid of remaining uses of
"backupable" which is terminology leftover from the original, flawed
design of BackupableDB. Now any DB can be backed up, using BackupEngine.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9792
Test Plan: CI
Reviewed By: ajkr
Differential Revision: D35334386
Pulled By: pdillinger
fbshipit-source-id: 2108a42b4575c8cccdfd791c549aae93ec2f3329
Summary:
min_log_number_to_keep denotes that the WALs whose numbers are below
this value **will** be deleted by RocksDB.
delete_wals_before will be used by RocksDB if
track_and_verify_wals_in_manifest is set to true. During recovery,
RocksDB uses the info encoded in delete_wals_before to reconstruct its
knowledge about what WALs to expect existing.
If these two tags are not encoded in the same VersionEdit, then it's
possible for min_log_number_to_keep=100 to exist, but
delete_wals_before=100 to be lost due to power failure. Subsequent
recovery will delete 99.log. If the db crashes again, the following
recovery will expect to see 99.log since there is no
delete_wals_before=100 in the MANIFEST, but the WAL is already deleted.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9766
Test Plan:
First of all, make check.
Second, format compatibility.
SHORT_TEST=1 ./tools/check_format_compatible.sh
Reviewed By: ltamasi
Differential Revision: D35203623
Pulled By: riversand963
fbshipit-source-id: 45623fc4b4b50d299d5e0f9559a3a4c5e9522c8f
Summary:
Right now we log a wrong error when DB::Open() fails. Fix it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9784
Test Plan: CI runs should pass
Reviewed By: ajkr, riversand963
Differential Revision: D35290203
fbshipit-source-id: ffc640afa27f6b0a2382ee153dc43f28d9e242be
Summary:
There is no need to release-and-acquire immediately when no listener is registered. This is
what we have been doing for `NotifyOnFlushBegin()`, `NotifyOnFlushCompleted()`, `NotifyOnCompactionBegin()`,
`NotifyOnCompactionCompleted()`, and some other `NotifyOnXX` methods in event_helpers.cc.
Do the same for `NotifyOnMemTableSealed ()`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9758
Test Plan: make check
Reviewed By: jay-zhuang
Differential Revision: D35159552
Pulled By: riversand963
fbshipit-source-id: 6e0aac50bd5c8f506d809b6638c33a7a28d1e87f
Summary:
much needed
Some other minor tweaks also
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9778
Test Plan: existing tests
Reviewed By: ajkr
Differential Revision: D35258195
Pulled By: pdillinger
fbshipit-source-id: 974ddafc23a540aacceb91da72e81593d818f99c
Summary:
In making `SstFileMetaData` inherit from `FileStorageInfo`, I
overlooked setting some `FileStorageInfo` fields when then default
`SstFileMetaData()` ctor is used. This affected `GetLiveFilesMetaData()`.
Also removed some buggy `static_cast<size_t>`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9769
Test Plan: Updated tests
Reviewed By: jay-zhuang
Differential Revision: D35220383
Pulled By: pdillinger
fbshipit-source-id: 05b4ee468258dbd3699517e1124838bf405fe7f8
Summary:
Although ColumnFamilySet comments say that DB mutex can be
freed during iteration, as long as you hold a ref while releasing DB
mutex, this is not quite true because UnrefAndTryDelete might delete cfd
right before it is needed to get ->next_ for the next iteration of the
loop.
This change solves the problem by making a wrapper class that makes such
iteration easier while handling the tricky details of UnrefAndTryDelete
on the previous cfd only after getting next_ in operator++.
FreeDeadColumnFamilies should already have been obsolete; this removes
it for good. Similarly, ColumnFamilySet::iterator doesn't need to check
for cfd with 0 refs, because those are immediately deleted.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9730
Test Plan:
was reported with ASAN on unit tests like
DBLogicalBlockSizeCacheTest.CreateColumnFamily (very rare); keep watching
Reviewed By: ltamasi
Differential Revision: D35038143
Pulled By: pdillinger
fbshipit-source-id: 0a5478d5be96c135343a00603711b7df43ae19c9
Summary:
There is a race condition if WAL tracking in the MANIFEST is enabled in a database that disables 2PC.
The race condition is between two background flush threads trying to install flush results to the MANIFEST.
Consider an example database with two column families: "default" (cfd0) and "cf1" (cfd1). Initially,
both column families have one mutable (active) memtable whose data backed by 6.log.
1. Trigger a manual flush for "cf1", creating a 7.log
2. Insert another key to "default", and trigger flush for "default", creating 8.log
3. BgFlushThread1 finishes writing 9.sst
4. BgFlushThread2 finishes writing 10.sst
```
Time BgFlushThread1 BgFlushThread2
| mutex_.Lock()
| precompute min_wal_to_keep as 6
| mutex_.Unlock()
| mutex_.Lock()
| precompute min_wal_to_keep as 6
| join MANIFEST write queue and mutex_.Unlock()
| write to MANIFEST
| mutex_.Lock()
| cfd1->log_number = 7
| Signal bg_flush_2 and mutex_.Unlock()
| wake up and mutex_.Lock()
| cfd0->log_number = 8
| FindObsoleteFiles() with job_context->log_number == 7
| mutex_.Unlock()
| PurgeObsoleteFiles() deletes 6.log
V
```
As shown in the above, BgFlushThread2 thinks that the min wal to keep is 6.log because "cf1" has unflushed data in 6.log (cf1.log_number=6).
Similarly, BgThread1 thinks that min wal to keep is also 6.log because "default" has unflushed data (default.log_number=6).
No WAL deletion will be written to MANIFEST because 6 is equal to `versions_->wals_.min_wal_number_to_keep`,
due to https://github.com/facebook/rocksdb/blob/7.1.fb/db/memtable_list.cc#L513:L514.
The bg flush thread that finishes last will perform file purging. `job_context.log_number` will be evaluated as 7, i.e.
the min wal that contains unflushed data, causing 6.log to be deleted. However, MANIFEST thinks 6.log should still exist.
If you close the db at this point, you won't be able to re-open it if `track_and_verify_wal_in_manifest` is true.
We must handle the case of multiple bg flush threads, and it is difficult for one bg flush thread to know
the correct min wal number until the other bg flush threads have finished committing to the manifest and updated
the `cfd::log_number`.
To fix this issue, we rename an existing variable `min_log_number_to_keep_2pc` to `min_log_number_to_keep`,
and use it to track WAL file deletion in non-2pc mode as well.
This variable is updated only 1) during recovery with mutex held, or 2) in the MANIFEST write thread.
`min_log_number_to_keep` means RocksDB will delete WALs below it, although there may be WALs
above it which are also obsolete. Formally, we will have [min_wal_to_keep, max_obsolete_wal]. During recovery, we
make sure that only WALs above max_obsolete_wal are checked and added back to `alive_log_files_`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9715
Test Plan:
```
make check
```
Also ran stress test below (with asan) to make sure it completes successfully.
```
TEST_TMPDIR=/dev/shm/rocksdb OPT=-g ASAN_OPTIONS=disable_coredump=0 \
CRASH_TEST_EXT_ARGS=--compression_type=zstd SKIP_FORMAT_BUCK_CHECKS=1 \
make J=52 -j52 blackbox_asan_crash_test
```
Reviewed By: ltamasi
Differential Revision: D34984412
Pulled By: riversand963
fbshipit-source-id: c7b21a8d84751bb55ea79c9f387103d21b231005
Summary:
Originally, a corruption will be returned by `DBImpl::WriteImpl(batch...)` if batch is
null. This is inaccurate since there is no data corruption.
Return `Status::InvalidArgument()` instead.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9744
Test Plan: make check
Reviewed By: ltamasi
Differential Revision: D35086268
Pulled By: riversand963
fbshipit-source-id: 677397b007a53bc25210eac0178d49c9797b5951
Summary:
Bloom filters generated by pre-7.0 releases are not read by
7.0.x releases (and vice-versa) due to changes to FilterPolicy::Name()
in https://github.com/facebook/rocksdb/issues/9590. This can severely impact read performance and read I/O on
upgrade or downgrade with existing DB, but not data correctness.
To fix, we go back using the old, unified name in SST metadata but (for
a while anyway) recognize the aliases that could be generated by early
7.0.x releases. This unfortunately requires a public API change to avoid
interfering with all the good changes from https://github.com/facebook/rocksdb/issues/9590, but the API change
only affects users with custom FilterPolicy, which should be very few.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9736
Test Plan:
manual
Generate DBs with
```
./db_bench.7.0 -db=/dev/shm/rocksdb.7.0 -bloom_bits=10 -cache_index_and_filter_blocks=1 -benchmarks=fillrandom -num=10000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0
```
and similar. Compare with
```
for IMPL in 6.29 7.0 fixed; do for DB in 6.29 7.0 fixed; do echo "Testing $IMPL on $DB:"; ./db_bench.$IMPL -db=/dev/shm/rocksdb.$DB -use_existing_db -readonly -bloom_bits=10 -benchmarks=readrandom -num=10000000 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -duration=10 2>&1 | grep micros/op; done; done
```
Results:
```
Testing 6.29 on 6.29:
readrandom : 34.381 micros/op 29085 ops/sec; 3.2 MB/s (291999 of 291999 found)
Testing 6.29 on 7.0:
readrandom : 190.443 micros/op 5249 ops/sec; 0.6 MB/s (52999 of 52999 found)
Testing 6.29 on fixed:
readrandom : 40.148 micros/op 24907 ops/sec; 2.8 MB/s (249999 of 249999 found)
Testing 7.0 on 6.29:
readrandom : 229.430 micros/op 4357 ops/sec; 0.5 MB/s (43999 of 43999 found)
Testing 7.0 on 7.0:
readrandom : 33.348 micros/op 29986 ops/sec; 3.3 MB/s (299999 of 299999 found)
Testing 7.0 on fixed:
readrandom : 152.734 micros/op 6546 ops/sec; 0.7 MB/s (65999 of 65999 found)
Testing fixed on 6.29:
readrandom : 32.024 micros/op 31224 ops/sec; 3.5 MB/s (312999 of 312999 found)
Testing fixed on 7.0:
readrandom : 33.990 micros/op 29390 ops/sec; 3.3 MB/s (294999 of 294999 found)
Testing fixed on fixed:
readrandom : 28.714 micros/op 34825 ops/sec; 3.9 MB/s (348999 of 348999 found)
```
Just paying attention to order of magnitude of ops/sec (short test
durations, lots of noise), it's clear that with the fix we can read <= 6.29
& >= 7.0 at full speed, where neither 6.29 nor 7.0 can on both. And 6.29
release can properly read fixed DB at full speed.
Reviewed By: siying, ajkr
Differential Revision: D35057844
Pulled By: pdillinger
fbshipit-source-id: a46893a6af4bf084375ebe4728066d00eb08f050
Summary:
Before this PR, the following command prints only the default column
family's information in the end:
```
ldb --db=. --hex manifest_dump --verbose
```
We should print all column families instead.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9719
Test Plan:
`make check` makes sure nothing breaks.
Generate a DB, use the above command to verify all column families are
printed.
Reviewed By: akankshamahajan15
Differential Revision: D34992453
Pulled By: riversand963
fbshipit-source-id: de1d38c4539cd89f74e1a6240ad7a6e2416bf198
Summary:
The param name force_erase may be misleading, since the handle is erased only if it has last reference even if the param is set true.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9728
Reviewed By: pdillinger
Differential Revision: D35038673
Pulled By: gitbw95
fbshipit-source-id: 0d16d1e8fed17b97eba7fb53207119332f659a5f
Summary:
Multiplier here should be 1e6 to get microseconds.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9695
Reviewed By: ajkr
Differential Revision: D34897086
Pulled By: jay-zhuang
fbshipit-source-id: 9c1d0811ea740ba0a007edc2da199edbd000b88b
Summary:
The goal of this change is to allow changes to the "current" (in
FileSystem) file temperatures to feed back into DB metadata, so that
they can inform decisions and stats reporting. In part because of
modular code factoring, it doesn't seem easy to do this automagically,
where opening an SST file and observing current Temperature different
from expected would trigger a change in metadata and DB manifest write
(essentially giving the deep read path access to the write path). It is also
difficult to do this while the DB is open because of the limitations of
LogAndApply.
This change allows updating file temperature metadata on a closed DB
using an experimental utility function UpdateManifestForFilesState()
or `ldb update_manifest --update_temperatures`. This should suffice for
"migration" scenarios where outside tooling has placed or re-arranged DB
files into a (different) tiered configuration without going through
RocksDB itself (currently, only compaction can change temperature
metadata).
Some details:
* Refactored and added unit test for `ldb unsafe_remove_sst_file` because
of shared functionality
* Pulled in autovector.h changes from https://github.com/facebook/rocksdb/issues/9546 to fix SuperVersionContext
move constructor (related to an older draft of this change)
Possible follow-up work:
* Support updating manifest with file checksums, such as when a
new checksum function is used and want existing DB metadata updated
for it.
* It's possible that for some repair scenarios, lighter weight than
full repair, we might want to support UpdateManifestForFilesState() to
modify critical file details like size or checksum using same
algorithm. But let's make sure these are differentiated from modifying
file details in ways that don't suspect corruption (or require extreme
trust).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9683
Test Plan: unit tests added
Reviewed By: jay-zhuang
Differential Revision: D34798828
Pulled By: pdillinger
fbshipit-source-id: cfd83e8fb10761d8c9e7f9c020d68c9106a95554
Summary:
On CircleCI MacOS instances, we have been seeing the following assertion error:
```
Assertion failed: (alive_log_files_tail_ == alive_log_files_.rbegin()), function WriteToWAL, file /Users/distiller/project/db/db_impl/db_impl_write.cc, line 1213.
Received signal 6 (Abort trap: 6)
#0 0x1
https://github.com/facebook/rocksdb/issues/1 abort (in libsystem_c.dylib) + 120
https://github.com/facebook/rocksdb/issues/2 err (in libsystem_c.dylib) + 0
https://github.com/facebook/rocksdb/issues/3 rocksdb::DBImpl::WriteToWAL(rocksdb::WriteBatch const&, rocksdb::log::Writer*, unsigned long long*, unsigned long long*, rocksdb::Env::IOPriority, bool, bool) (in librocksdb.7.0.0.dylib) (db_impl_write.cc:1213)
https://github.com/facebook/rocksdb/issues/4 rocksdb::DBImpl::WriteToWAL(rocksdb::WriteThread::WriteGroup const&, rocksdb::log::Writer*, unsigned long long*, bool, bool, unsigned long long) (in librocksdb.7.0.0.dylib) (db_impl_write.cc:1251)
https://github.com/facebook/rocksdb/issues/5 rocksdb::DBImpl::WriteImpl(rocksdb::WriteOptions const&, rocksdb::WriteBatch*, rocksdb::WriteCallback*, unsigned long long*, unsigned long long, bool, unsigned long long*, unsigned long, rocksdb::PreReleaseCallback*) (in librocksdb.7.0.0.dylib) (db_impl_ rite.cc:421)
https://github.com/facebook/rocksdb/issues/6 rocksdb::DBImpl::Write(rocksdb::WriteOptions const&, rocksdb::WriteBatch*) (in librocksdb.7.0.0.dylib) (db_impl_write.cc:109)
https://github.com/facebook/rocksdb/issues/7 rocksdb::DB::Put(rocksdb::WriteOptions const&, rocksdb::ColumnFamilyHandle*, rocksdb::Slice const&, rocksdb::Slice const&, rocksdb::Slice const&) (in librocksdb.7.0.0.dylib) (db_impl_write.cc:2159)
https://github.com/facebook/rocksdb/issues/8 rocksdb::DBImpl::Put(rocksdb::WriteOptions const&, rocksdb::ColumnFamilyHandle*, rocksdb::Slice const&, rocksdb::Slice const&, rocksdb::Slice const&) (in librocksdb.7.0.0.dylib) (db_impl_write.cc:37)
https://github.com/facebook/rocksdb/issues/9 rocksdb::DB::Put(rocksdb::WriteOptions const&, rocksdb::Slice const&, rocksdb::Slice const&, rocksdb::Slice const&) (in librocksdb.7.0.0.dylib) (db.h:382)
https://github.com/facebook/rocksdb/issues/10 rocksdb::DBBasicTestWithTimestampPrefixSeek_IterateWithPrefix_Test::TestBody() (in db_with_timestamp_basic_test) (db_with_timestamp_basic_test.cc:2926)
https://github.com/facebook/rocksdb/issues/11 void testing::internal::HandleSehExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) (in db_with_timestamp_basic_test) (gtest-all.cc:3899)
https://github.com/facebook/rocksdb/issues/12 void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::*)(), char const*) (in db_with_timestamp_basic_test) (gtest-all.cc:3935)
https://github.com/facebook/rocksdb/issues/13 testing::Test::Run() (in db_with_timestamp_basic_test) (gtest-all.cc:3980)
https://github.com/facebook/rocksdb/issues/14 testing::TestInfo::Run() (in db_with_timestamp_basic_test) (gtest-all.cc:4153)
https://github.com/facebook/rocksdb/issues/15 testing::TestCase::Run() (in db_with_timestamp_basic_test) (gtest-all.cc:4266)
https://github.com/facebook/rocksdb/issues/16 testing::internal::UnitTestImpl::RunAllTests() (in db_with_timestamp_basic_test) (gtest-all.cc:6632)
https://github.com/facebook/rocksdb/issues/17 bool testing::internal::HandleSehExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) (in db_with_timestamp_basic_test) (gtest-all.cc:3899)
https://github.com/facebook/rocksdb/issues/18 bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::*)(), char const*) (in db_with_timestamp_basic_test) (gtest-all.cc:3935)
https://github.com/facebook/rocksdb/issues/19 testing::UnitTest::Run() (in db_with_timestamp_basic_test) (gtest-all.cc:6242)
https://github.com/facebook/rocksdb/issues/20 RUN_ALL_TESTS() (in db_with_timestamp_basic_test) (gtest.h:22110)
https://github.com/facebook/rocksdb/issues/21 main (in db_with_timestamp_basic_test) (db_with_timestamp_basic_test.cc:3150)
https://github.com/facebook/rocksdb/issues/22 start (in libdyld.dylib) + 1
```
It's likely caused by concurrent, unprotected access to the deque, even though `back()` is never popped,
and we are comparing `rbegin()` with a cached `riterator`. To be safe, do the comparison only if we have mutex.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9717
Test Plan:
One example
Ssh to one CircleCI MacOS instance.
```
gtest-parallel -r 1000 -w 8 ./db_test --gtest_filter=DBTest.FlushesInParallelWithCompactRange
```
Reviewed By: pdillinger
Differential Revision: D34990696
Pulled By: riversand963
fbshipit-source-id: 62dd48ae6fedbda53d0a64d73de9b948b4c26eee
Summary:
The primary goal of this change is to add support for backing up and
restoring (applying on restore) file temperature metadata, without
committing to either the DB manifest or the FS reported "current"
temperatures being exclusive "source of truth".
To achieve this goal, we need to add temperature information to backup
metadata, which requires updated backup meta schema. Fortunately I
prepared for this in https://github.com/facebook/rocksdb/issues/8069, which began forward compatibility in version
6.19.0 for this kind of schema update. (Previously, backup meta schema
was not extensible! Making this schema update public will allow some
other "nice to have" features like taking backups with hard links, and
avoiding crc32c checksum computation when another checksum is already
available.) While schema version 2 is newly public, the default schema
version is still 1. Until we change the default, users will need to set
to 2 to enable features like temperature data backup+restore. New
metadata like temperature information will be ignored with a warning
in versions before this change and since 6.19.0. The metadata is
considered ignorable because a functioning DB can be restored without
it.
Some detail:
* Some renaming because "future schema" is now just public schema 2.
* Initialize some atomics in TestFs (linter reported)
* Add temperature hint support to SstFileDumper (used by BackupEngine)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9660
Test Plan:
related unit test majorly updated for the new functionality,
including some shared testing support for tracking temperatures in a FS.
Some other tests and testing hooks into production code also updated for
making the backup meta schema change public.
Reviewed By: ajkr
Differential Revision: D34686968
Pulled By: pdillinger
fbshipit-source-id: 3ac1fa3e67ee97ca8a5103d79cc87d872c1d862a
Summary:
Fix and enhance the background error recovery logic to handle the
following situations -
1. Background read errors during flush/compaction (previously was
resulting in unrecoverable state)
2. Fix auto recovery failure on read/write errors during atomic flush.
It was failing due to a bug in setting the resuming_from_bg_err variable
in AtomicFlushMemTablesToOutputFiles.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9679
Test Plan: Add new unit tests in error_handler_fs_test
Reviewed By: riversand963
Differential Revision: D34770097
Pulled By: anand1976
fbshipit-source-id: 136da973a28d684b9c74bdf668519b0cbbbe1742
Summary:
In https://github.com/facebook/rocksdb/issues/9659, when `DisableManualCompaction()` is issued, the foreground
manual compaction thread does not have to wait background compaction
thread to finish. Which could be a problem that the user re-enable
manual compaction with `EnableManualCompaction()`, it may re-enable the
BG compaction which supposed be cancelled.
This patch makes the FG compaction wait on
`manual_compaction_state.done`, which either be set by BG compaction or
Unschedule callback. Then when FG manual compaction thread returns, it
should not have BG compaction running. So shared_ptr is no longer needed
for `manual_compaction_state`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9694
Test Plan: a StressTest and unittest
Reviewed By: ajkr
Differential Revision: D34885472
Pulled By: jay-zhuang
fbshipit-source-id: e6476175b43e8c59cd49f5c09241036a0716c274
Summary:
PR9686 makes `WriteToWAL()` call `assert(...!=rend())` while not holding
db mutex or log mutex. Another thread may concurrently call
`pop_front()`, causing race condition.
To fix, assert only if mutex is held.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9698
Test Plan: COMPILE_WITH_TSAN=1 make check
Reviewed By: jay-zhuang
Differential Revision: D34898535
Pulled By: riversand963
fbshipit-source-id: 1ddfa5bf1b6ae8d409cab6ff6e1b5321c6803da9
Summary:
In the original code, the value of `NO_FILE_OPENS` corresponding to the Ticker item will be increased regardless of whether the file is successfully opened or not. Even counts are repeated, which can lead to skewed counts.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9677
Reviewed By: jay-zhuang
Differential Revision: D34725733
Pulled By: ajkr
fbshipit-source-id: 841234ed03802c0105fd2107d82a740265ead576
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9686
According to https://www.cplusplus.com/reference/deque/deque/back/,
"
The container is accessed (neither the const nor the non-const versions modify the container).
The last element is potentially accessed or modified by the caller. Concurrently accessing or modifying other elements is safe.
"
Also according to https://www.cplusplus.com/reference/deque/deque/pop_front/,
"
The container is modified.
The first element is modified. Concurrently accessing or modifying other elements is safe (although see iterator validity above).
"
In RocksDB, we never pop the last element of `DBImpl::alive_log_files_`. We have been
exploiting this fact and the above two properties when ensuring correctness when
`DBImpl::alive_log_files_` may be accessed concurrently. Specifically, it can be accessed
in the write path when db mutex is released. Sometimes, the log_mute_ is held. It can also be accessed in `FindObsoleteFiles()`
when db mutex is always held. It can also be accessed
during recovery when db mutex is also held.
Given the fact that we never pop the last element of alive_log_files_, we currently do not
acquire additional locks when accessing it in `WriteToWAL()` as follows
```
alive_log_files_.back().AddSize(log_entry.size());
```
This is problematic.
Check source code of deque.h
```
back() _GLIBCXX_NOEXCEPT
{
__glibcxx_requires_nonempty();
...
}
pop_front() _GLIBCXX_NOEXCEPT
{
...
if (this->_M_impl._M_start._M_cur
!= this->_M_impl._M_start._M_last - 1)
{
...
++this->_M_impl._M_start._M_cur;
}
...
}
```
`back()` will actually call `__glibcxx_requires_nonempty()` first.
If `__glibcxx_requires_nonempty()` is enabled and not an empty macro,
it will call `empty()`
```
bool empty() {
return this->_M_impl._M_finish == this->_M_impl._M_start;
}
```
You can see that it will access `this->_M_impl._M_start`, racing with `pop_front()`.
Therefore, TSAN will actually catch the bug in this case.
To be able to use TSAN on our library and unit tests, we should always coordinate
concurrent accesses to STL containers properly.
We need to pass information about db mutex and log mutex into `WriteToWAL()`, otherwise
it's impossible to know which mutex to acquire inside the function.
To fix this, we can catch the tail of `alive_log_files_` by reference, so that we do not have to call `back()` in `WriteToWAL()`.
Reviewed By: pdillinger
Differential Revision: D34780309
fbshipit-source-id: 1def9821f0c437f2736c6a26445d75890377889b
Summary:
https://github.com/facebook/rocksdb/issues/9625 didn't change the unschedule condition which was waiting for the background thread to clean-up the compaction.
make sure we only unschedule the task when it's scheduled.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9659
Reviewed By: ajkr
Differential Revision: D34651820
Pulled By: jay-zhuang
fbshipit-source-id: 23f42081b15ec8886cd81cbf131b116e0c74dc2f
Summary:
Timer crash when multiple DB instances doing heavy DB open and close
operations concurrently. Which is caused by adding a timer task with
smaller timestamp than the current running task. Fix it by moving the
getting new task timestamp part within timer mutex protection.
And other fixes:
- Disallow adding duplicated function name to timer
- Fix a minor memory leak in timer when a running task is cancelled
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9656
Reviewed By: ajkr
Differential Revision: D34626296
Pulled By: jay-zhuang
fbshipit-source-id: 6b6d96a5149746bf503546244912a9e41a0c5f6b
Summary:
As disscussed in (https://github.com/facebook/rocksdb/issues/9223), Here added a new API named DB::OpenAndTrimHistory, this API will open DB and trim data to the timestamp specofied by **trim_ts** (The data with newer timestamp than specified trim bound will be removed). This API should only be used at a timestamp-enabled db instance recovery.
And this PR implemented a new iterator named HistoryTrimmingIterator to support trimming history with a new API named DB::OpenAndTrimHistory. HistoryTrimmingIterator wrapped around the underlying InternalITerator such that keys whose timestamps newer than **trim_ts** should not be returned to the compaction iterator while **trim_ts** is not null.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9410
Reviewed By: ltamasi
Differential Revision: D34410207
Pulled By: riversand963
fbshipit-source-id: e54049dc234eccd673244c566b15df58df5a6236
Summary:
Change the `MemPurge` code to address a failure during a crash test reported in https://github.com/facebook/rocksdb/issues/8958.
### Details and results of the crash investigation:
These failures happened in a specific scenario where the list of immutable tables was composed of 2 or more memtables, and the last memtable was the output of a previous `Mempurge` operation. Because the `PickMemtablesToFlush` function included a sorting of the memtables (previous PR related to the Mempurge project), and because the `VersionEdit` of the flush class is piggybacked onto a single one of these memtables, the `VersionEdit` was not properly selected and applied to the `VersionSet` of the DB. Since the `VersionSet` was not edited properly, the database was losing track of the SST file created during the flush process, which was subsequently deleted (and as you can expect, caused the tests to crash).
The following command consistently failed, which was quite convenient to investigate the issue:
`$ while rm -rf /dev/shm/single_stress && ./db_stress --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/single_stress --experimental_mempurge_threshold=5.493146827397074 --flush_one_in=10000 --reopen=0 --write_buffer_size=262144 --value_size_mult=33 --max_write_buffer_number=3 -ops_per_thread=10000; do : ; done`
### Solution proposed
The memtables are no longer sorted based on their `memtableID` in the `PickMemtablesToFlush` function. Additionally, the `next_log_number` of the memtable created as an output of the `Mempurge` function now takes in the correct value (the log number of the first memtable being mempurged). Finally, the VersionEdit object of the flush class now takes the maximum `next_log_number` of the stack of memtables being flushed, which doesnt change anything when Mempurge is `off` but becomes necessary when Mempurge is `on`.
### Testing of the solution
The following command no longer fails:
``$ while rm -rf /dev/shm/single_stress && ./db_stress --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/single_stress --experimental_mempurge_threshold=5.493146827397074 --flush_one_in=10000 --reopen=0 --write_buffer_size=262144 --value_size_mult=33 --max_write_buffer_number=3 -ops_per_thread=10000; do : ; done``
Additionally, I ran `db_crashtest` (`whitebox` and `blackbox`) for 2.5 hours with MemPurge on and did not observe any crash.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9671
Reviewed By: pdillinger
Differential Revision: D34697424
Pulled By: bjlemaire
fbshipit-source-id: d1ab675b361904351ac81a35c184030e52222874
Summary:
Integrate the streaming compress/uncompress API into WAL compression.
The streaming compression object is stored in the log_writer along with a reusable output buffer to store the compressed buffer(s).
The streaming uncompress object is stored in the log_reader along with a reusable output buffer to store the uncompressed buffer(s).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9642
Test Plan:
Added unit tests to verify different scenarios - large buffers, split compressed buffers, etc.
Future optimizations:
The overhead for small records is quite high, so it makes sense to compress only buffers above a certain threshold and use a separate record type to indicate that those records are compressed.
Reviewed By: anand1976
Differential Revision: D34709167
Pulled By: sidroyc
fbshipit-source-id: a37a3cd1301adff6152fb3fcd23726106af07dd4
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9629
Pessimistic transactions use pessimistic concurrency control, i.e. locking. Keys are
locked upon first operation that writes the key or has the intention of writing. For example,
`PessimisticTransaction::Put()`, `PessimisticTransaction::Delete()`,
`PessimisticTransaction::SingleDelete()` will write to or delete a key, while
`PessimisticTransaction::GetForUpdate()` is used by application to indicate
to RocksDB that the transaction has the intention of performing write operation later
in the same transaction.
Pessimistic transactions support two-phase commit (2PC). A transaction can be
`Prepared()`'ed and then `Commit()`. The prepare phase is similar to a promise: once
`Prepare()` succeeds, the transaction has acquired the necessary resources to commit.
The resources include locks, persistence of WAL, etc.
Write-committed transaction is the default pessimistic transaction implementation. In
RocksDB write-committed transaction, `Prepare()` will write data to the WAL as a prepare
section. `Commit()` will write a commit marker to the WAL and then write data to the
memtables. While writing to the memtables, different keys in the transaction's write batch
will be assigned different sequence numbers in ascending order.
Until commit/rollback, the transaction holds locks on the keys so that no other transaction
can write to the same keys. Furthermore, the keys' sequence numbers represent the order
in which they are committed and should be made visible. This is convenient for us to
implement support for user-defined timestamps.
Since column families with and without timestamps can co-exist in the same database,
a transaction may or may not involve timestamps. Based on this observation, we add two
optional members to each `PessimisticTransaction`, `read_timestamp_` and
`commit_timestamp_`. If no key in the transaction's write batch has timestamp, then
setting these two variables do not have any effect. For the rest of this commit, we discuss
only the cases when these two variables are meaningful.
read_timestamp_ is used mainly for validation, and should be set before first call to
`GetForUpdate()`. Otherwise, the latter will return non-ok status. `GetForUpdate()` calls
`TryLock()` that can verify if another transaction has written the same key since
`read_timestamp_` till this call to `GetForUpdate()`. If another transaction has indeed
written the same key, then validation fails, and RocksDB allows this transaction to
refine `read_timestamp_` by increasing it. Note that a transaction can still use `Get()`
with a different timestamp to read, but the result of the read should not be used to
determine data that will be written later.
commit_timestamp_ must be set after finishing writing and before transaction commit.
This applies to both 2PC and non-2PC cases. In the case of 2PC, it's usually set after
prepare phase succeeds.
We currently require that the commit timestamp be chosen after all keys are locked. This
means we disallow the `TransactionDB`-level APIs if user-defined timestamp is used
by the transaction. Specifically, calling `PessimisticTransactionDB::Put()`,
`PessimisticTransactionDB::Delete()`, `PessimisticTransactionDB::SingleDelete()`,
etc. will return non-ok status because they specify timestamps before locking the keys.
Users are also prompted to use the `Transaction` APIs when they receive the non-ok status.
Reviewed By: ltamasi
Differential Revision: D31822445
fbshipit-source-id: b82abf8e230216dc89cc519564a588224a88fd43
