Summary:
The following sequence of events can cause silent data loss for write-committed
transactions.
```
Time thread 1 bg flush
| db->Put("a")
| txn = NewTxn()
| txn->Put("b", "v")
| txn->Prepare() // writes only to 5.log
| db->SwitchMemtable() // memtable 1 has "a"
| // close 5.log,
| // creates 8.log
| trigger flush
| pick memtable 1
| unlock db mutex
| write new sst
| txn->ctwb->Put("gtid", "1") // writes 8.log
| txn->Commit() // writes to 8.log
| // writes to memtable 2
| compute min_log_number_to_keep_2pc, this
| will be 8 (incorrect).
|
| Purge obsolete wals, including 5.log
|
V
```
At this point, writes of txn exists only in memtable. Close db without flush because db thinks the data in
memtable are backed by log. Then reopen, the writes are lost except key-value pair {"gtid"->"1"},
only the commit marker of txn is in 8.log
The reason lies in `PrecomputeMinLogNumberToKeep2PC()` which calls `FindMinPrepLogReferencedByMemTable()`.
In the above example, when bg flush thread tries to find obsolete wals, it uses the information
computed by `PrecomputeMinLogNumberToKeep2PC()`. The return value of `PrecomputeMinLogNumberToKeep2PC()`
depends on three components
- `PrecomputeMinLogNumberToKeepNon2PC()`. This represents the WAL that has unflushed data. As the name of this method suggests, it does not account for 2PC. Although the keys reside in the prepare section of a previous WAL, the column family references the current WAL when they are actually inserted into the memtable during txn commit.
- `prep_tracker->FindMinLogContainingOutstandingPrep()`. This represents the WAL with a prepare section but the txn hasn't committed.
- `FindMinPrepLogReferencedByMemTable()`. This represents the WAL on which some memtables (mutable and immutable) depend for their unflushed data.
The bug lies in `FindMinPrepLogReferencedByMemTable()`. Originally, this function skips checking the column families
that are being flushed, but the unit test added in this PR shows that they should not be. In this unit test, there is
only the default column family, and one of its memtables has unflushed data backed by a prepare section in 5.log.
We should return this information via `FindMinPrepLogReferencedByMemTable()`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9571
Test Plan:
```
./transaction_test --gtest_filter=*/TransactionTest.SwitchMemtableDuringPrepareAndCommit_WC/*
make check
```
Reviewed By: siying
Differential Revision: D34235236
Pulled By: riversand963
fbshipit-source-id: 120eb21a666728a38dda77b96276c6af72b008b1
Summary:
Range Locking supports Lock Escalation. Lock Escalation is invoked when
lock memory is nearly exhausted and it reduced the amount of memory used
by joining adjacent locks.
Bridging the gap between certain locks has adverse effects. For example,
in MyRocks it is not a good idea to bridge the gap between locks in
different indexes, as that get the lock to cover large portions of
indexes, or even entire indexes.
Resolve this by introducing Escalation Barrier. The escalation process
will call the user-provided barrier callback function:
bool(const Endpoint& a, const Endpoint& b)
If the function returns true, there's a barrier between a and b and Lock
Escalation will not try to bridge the gap between a and b.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9290
Reviewed By: akankshamahajan15
Differential Revision: D33486753
Pulled By: riversand963
fbshipit-source-id: f97910b67aba0579ea1d35f523ca6863d3dd018e
Summary:
As title.
This is part of an fb-internal task.
First, remove all `using namespace` statements if applicable.
Next, utilize multiple build platforms and see if anything is broken.
Should anything become broken, fix the compilation errors with as little extra change as possible.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9369
Test Plan:
internal build and make check
make clean && make static_lib && cd examples && make all
Reviewed By: pdillinger
Differential Revision: D33517260
Pulled By: riversand963
fbshipit-source-id: 3fc4ce6402a073421dfd9a9b2d1c79441dca7a40
Summary:
In order to support old-style regex function registration, restored the original "Register<T>(string, Factory)" method using regular expressions. The PatternEntry methods were left in place but renamed to AddFactory. The goal is to allow for the deprecation of the original regex Registry method in an upcoming release.
Added modes to the PatternEntry kMatchZeroOrMore and kMatchAtLeastOne to match * or +, respectively (kMatchAtLeastOne was the original behavior).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9362
Reviewed By: pdillinger
Differential Revision: D33432562
Pulled By: mrambacher
fbshipit-source-id: ed88ab3f9a2ad0d525c7bd1692873f9bb3209d02
Summary:
Allows the Env to have options (Configurable) and loads like other Customizable classes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9293
Reviewed By: pdillinger, zhichao-cao
Differential Revision: D33181591
Pulled By: mrambacher
fbshipit-source-id: 55e823886c654d214eda9eedd45ccdc54dac14d7
Summary:
Added new ObjectLibrary::Entry classes to replace/reduce the use of Regex. For simple factories that only do name matching, there are "StringEntry" and "AltStringEntry" classes. For classes that use some semblance of regular expressions, there is a PatternEntry class that can match a name and prefixes. There is also a class for Customizable::IndividualId format matches.
Added tests for the new derivative classes and got all unit tests to pass.
Resolves https://github.com/facebook/rocksdb/issues/9225.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9264
Reviewed By: pdillinger
Differential Revision: D33062001
Pulled By: mrambacher
fbshipit-source-id: c2d2143bd2d38bdf522705c8280c35381b135c03
Summary:
The failure looked like this:
```
utilities/backupable/backupable_db_test.cc:3161: Failure
Value of: db_chroot_env_->FileExists(prev_manifest_path).IsNotFound()
Actual: false
Expected: true
```
The failure could be coerced consistently with the following patch:
```
diff --git a/db/db_impl/db_impl_compaction_flush.cc b/db/db_impl/db_impl_compaction_flush.cc
index 80410f671..637636791 100644
--- a/db/db_impl/db_impl_compaction_flush.cc
+++ b/db/db_impl/db_impl_compaction_flush.cc
@@ -2772,6 +2772,8 @@ void DBImpl::BackgroundCallFlush(Env::Priority thread_pri) {
if (job_context.HaveSomethingToClean() ||
job_context.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
mutex_.Unlock();
+ bg_cv_.SignalAll();
+ sleep(1);
TEST_SYNC_POINT("DBImpl::BackgroundCallFlush:FilesFound");
// Have to flush the info logs before bg_flush_scheduled_--
// because if bg_flush_scheduled_ becomes 0 and the lock is
```
The cause was a familiar problem, which is manual flush/compaction may
return before files they obsoleted are removed. The solution is just to
wait for "scheduled" work to complete, which includes all phases
including cleanup.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9327
Test Plan:
after this PR, even the above patch to coerce the bug cannot
cause the test to fail.
Reviewed By: riversand963
Differential Revision: D33252208
Pulled By: ajkr
fbshipit-source-id: 720a7eaca58c7247d221911fffe3d5e1dbf581e9
Summary:
locktree is a module providing Range Locking. It has a counter for
the number of times a lock acquisition request was blocked by an
existing conflicting lock and had to wait for it to be released.
Expose this counter in RangeLockManagerHandle::Counters::lock_wait_count.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9289
Reviewed By: jay-zhuang
Differential Revision: D33079182
Pulled By: riversand963
fbshipit-source-id: 25b1a362d9da247536ab5007bd15900b319f139e
Summary:
- Make MemoryAllocator and its implementations into a Customizable class.
- Added a "DefaultMemoryAllocator" which uses new and delete
- Added a "CountedMemoryAllocator" that counts the number of allocs and free
- Updated the existing tests to use these new allocators
- Changed the memkind allocator test into a generic test that can test the various allocators.
- Added tests for creating all of the allocators
- Added tests to verify/create the JemallocNodumpAllocator using its options.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8980
Reviewed By: zhichao-cao
Differential Revision: D32990403
Pulled By: mrambacher
fbshipit-source-id: 6fdfe8218c10dd8dfef34344a08201be1fa95c76
Summary:
This change standardizes on a new 16-byte cache key format for
block cache (incl compressed and secondary) and persistent cache (but
not table cache and row cache).
The goal is a really fast cache key with practically ideal stability and
uniqueness properties without external dependencies (e.g. from FileSystem).
A fixed key size of 16 bytes should enable future optimizations to the
concurrent hash table for block cache, which is a heavy CPU user /
bottleneck, but there appears to be measurable performance improvement
even with no changes to LRUCache.
This change replaces a lot of disjointed and ugly code handling cache
keys with calls to a simple, clean new internal API (cache_key.h).
(Preserving the old cache key logic under an option would be very ugly
and likely negate the performance gain of the new approach. Complete
replacement carries some inherent risk, but I think that's acceptable
with sufficient analysis and testing.)
The scheme for encoding new cache keys is complicated but explained
in cache_key.cc.
Also: EndianSwapValue is moved to math.h to be next to other bit
operations. (Explains some new include "math.h".) ReverseBits operation
added and unit tests added to hash_test for both.
Fixes https://github.com/facebook/rocksdb/issues/7405 (presuming a root cause)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9126
Test Plan:
### Basic correctness
Several tests needed updates to work with the new functionality, mostly
because we are no longer relying on filesystem for stable cache keys
so table builders & readers need more context info to agree on cache
keys. This functionality is so core, a huge number of existing tests
exercise the cache key functionality.
### Performance
Create db with
`TEST_TMPDIR=/dev/shm ./db_bench -bloom_bits=10 -benchmarks=fillrandom -num=3000000 -partition_index_and_filters`
And test performance with
`TEST_TMPDIR=/dev/shm ./db_bench -readonly -use_existing_db -bloom_bits=10 -benchmarks=readrandom -num=3000000 -duration=30 -cache_index_and_filter_blocks -cache_size=250000 -threads=4`
using DEBUG_LEVEL=0 and simultaneous before & after runs.
Before ops/sec, avg over 100 runs: 121924
After ops/sec, avg over 100 runs: 125385 (+2.8%)
### Collision probability
I have built a tool, ./cache_bench -stress_cache_key to broadly simulate host-wide cache activity
over many months, by making some pessimistic simplifying assumptions:
* Every generated file has a cache entry for every byte offset in the file (contiguous range of cache keys)
* All of every file is cached for its entire lifetime
We use a simple table with skewed address assignment and replacement on address collision
to simulate files coming & going, with quite a variance (super-Poisson) in ages. Some output
with `./cache_bench -stress_cache_key -sck_keep_bits=40`:
```
Total cache or DBs size: 32TiB Writing 925.926 MiB/s or 76.2939TiB/day
Multiply by 9.22337e+18 to correct for simulation losses (but still assume whole file cached)
```
These come from default settings of 2.5M files per day of 32 MB each, and
`-sck_keep_bits=40` means that to represent a single file, we are only keeping 40 bits of
the 128-bit cache key. With file size of 2\*\*25 contiguous keys (pessimistic), our simulation
is about 2\*\*(128-40-25) or about 9 billion billion times more prone to collision than reality.
More default assumptions, relatively pessimistic:
* 100 DBs in same process (doesn't matter much)
* Re-open DB in same process (new session ID related to old session ID) on average
every 100 files generated
* Restart process (all new session IDs unrelated to old) 24 times per day
After enough data, we get a result at the end:
```
(keep 40 bits) 17 collisions after 2 x 90 days, est 10.5882 days between (9.76592e+19 corrected)
```
If we believe the (pessimistic) simulation and the mathematical generalization, we would need to run a billion machines all for 97 billion days to expect a cache key collision. To help verify that our generalization ("corrected") is robust, we can make our simulation more precise with `-sck_keep_bits=41` and `42`, which takes more running time to get enough data:
```
(keep 41 bits) 16 collisions after 4 x 90 days, est 22.5 days between (1.03763e+20 corrected)
(keep 42 bits) 19 collisions after 10 x 90 days, est 47.3684 days between (1.09224e+20 corrected)
```
The generalized prediction still holds. With the `-sck_randomize` option, we can see that we are beating "random" cache keys (except offsets still non-randomized) by a modest amount (roughly 20x less collision prone than random), which should make us reasonably comfortable even in "degenerate" cases:
```
197 collisions after 1 x 90 days, est 0.456853 days between (4.21372e+18 corrected)
```
I've run other tests to validate other conditions behave as expected, never behaving "worse than random" unless we start chopping off structured data.
Reviewed By: zhichao-cao
Differential Revision: D33171746
Pulled By: pdillinger
fbshipit-source-id: f16a57e369ed37be5e7e33525ace848d0537c88f
Summary:
`db_stress` is a user of `FaultInjectionTestFS`. After injecting a write error, `db_stress` probabilistically determins
data drop (https://github.com/facebook/rocksdb/blob/6.27.fb/db_stress_tool/db_stress_test_base.cc#L2615:L2619).
In some of our recent runs of `db_stress`, we found duplicate trailing entries corresponding to file trivial move in
the MANIFEST, causing the recovery to fail, because the file move operation is not idempotent: you cannot delete a
file from a given level twice.
Investigation suggests that data buffering in both `WritableFileWriter` and `FaultInjectionTestFS` may be the root cause.
WritableFileWriter buffers data to write in a memory buffer, `WritableFileWriter::buf_`. After each
`WriteBuffered()`/`WriteBufferedWithChecksum()` succeeds, the `buf_` is cleared.
If the underlying file `WritableFileWriter::writable_file_` is opened in buffered IO mode, then `FaultInjectionTestFS`
buffers data written for each file until next file sync. After an injected error, user of `FaultInjectionFS` can
choose to drop some or none of previously buffered data. If `db_stress` does not drop any unsynced data, then
such data will still exist in the `FaultInjectionTestFS`'s buffer.
Existing implementation of `WritableileWriter::WriteBuffered()` does not clear `buf_` if there is an error. This may lead
to the data being buffered two copies: one in `WritableFileWriter`, and another in `FaultInjectionTestFS`.
We also know that the `WritableFileWriter` of MANIFEST file will close upon an error. During `Close()`, it will flush the
content in `buf_`. If no write error is injected to `FaultInjectionTestFS` this time, then we end up with two copies of the
data appended to the file.
To fix, we clear the `WritableFileWriter::buf_` upon failure as well. We focus this PR on files opened in non-direct mode.
This PR includes a unit test to reproduce a case when write error injection
to `WritableFile` can cause duplicate trailing entries.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9236
Test Plan: make check
Reviewed By: zhichao-cao
Differential Revision: D33033984
Pulled By: riversand963
fbshipit-source-id: ebfa5a0db8cbf1ed73100528b34fcba543c5db31
Summary:
Context:
[Rapid thread creation and deletion](https://github.com/facebook/rocksdb/blob/6.27.fb/utilities/transactions/write_prepared_transaction_test.cc#L439-L444) in `SnapshotConcurrentAccessTest.SnapshotConcurrentAcces` inside a [potentially big loop](https://github.com/facebook/rocksdb/blob/6.27.fb/utilities/transactions/write_prepared_transaction_test.cc#L1238-L1248) can lead to heavy-loading the system with many threads due to delay in actually cleaning up thread's resource in the kernel sometime. We ran into some [flaky failure](https://app.circleci.com/pipelines/github/facebook/rocksdb/10383/workflows/136f1005-80a9-4515-aee9-fe36ac6462a1/jobs/253289) in CI and reproduced it by below:
- Command
```
Added `ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();` like https://github.com/facebook/rocksdb/pull/9276
DEBUG_LEVEL=2 make -j56 write_prepared_transaction_test
GTEST_CATCH_EXCEPTIONS=0 ~/gtest-parallel/gtest-parallel -r 200 -w 200 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
```
- Stack, where `write_prepared_transaction_test.cc:442` in `https://github.com/facebook/rocksdb/issues/9` points to thread creation
```
[ RUN ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
....terminate called after throwing an instance of 'std::system_error'
what(): Resource temporarily unavailable
Received signal 6 (Aborted)
#0 /lib/x86_64-linux-gnu/libc.so.6(gsignal+0x38) [0x7fc114f39438]
...
https://github.com/facebook/rocksdb/issues/7 /usr/lib/x86_64-linux-gnu/libstdc++.so.6(+0xb8e73) [0x7fc1158a5e73] ?? ??:0
https://github.com/facebook/rocksdb/issues/8 ./write_prepared_transaction_test() [0x4ca86c] std:🧵:thread<rocksdb::WritePreparedTransactionTestBase::SnapshotConcurrentAccessTestInternal(rocksdb::WritePreparedTxnDB*, std::vector<unsigned long, std::allocator<unsigned long> > const&, std::vector<unsigned long, std::allocator<unsigned long> const&, rocksdb::WritePreparedTxnDB::CommitEntry&, unsigned long&, unsigned long, unsigned long, unsigned long, unsigned long)::{lambda()https://github.com/facebook/rocksdb/issues/1}>(rocksdb::WritePreparedTransactionTestBase::SnapshotConcurrentAccessTestInternal(rocksdb::WritePreparedTxnDB*, s d::vector<unsigned long, std::allocator<unsigned long> > const&, std::vector<unsigned long, std::allocator<unsigned long> > const&, rocksdb::WritePreparedTxnDB::CommitEntry&, unsigned long&, unsigned long, unsigned long, unsigned long, unsigned long)::{l mbda()https://github.com/facebook/rocksdb/issues/1}&&) /usr/include/c++/5/thread:137 (discriminator 4)
https://github.com/facebook/rocksdb/issues/9 ./write_prepared_transaction_test() [0x4bb80c] rocksdb::WritePreparedTransactionTestBase::SnapshotConcurrentAccessTestInternal(rocksdb::WritePreparedTxnDB*, std::vector<unsigned long, std::allocator<unsigned long> > const&, std::vector<unsigned long, std::allocator<unsigned long> > const&, rocksdb::W itePreparedTxnDB::CommitEntry&, unsigned long&, unsigned long, unsigned long, unsigned long, unsigned long) /home/circleci/project/utilities/transactions/write_prepared_transaction_test.cc:442
https://github.com/facebook/rocksdb/issues/10 ./write_prepared_transaction_test() [0x4407b6] rocksdb::SnapshotConcurrentAccessTest_SnapshotConcurrentAccess_Test::TestBody() /home/circleci/project/utilities/transactions/write_prepared_transaction_test.cc:1244
...
[109/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1 returned/aborted with exit code -6 (34462 ms)
```
- Move thread 2's work into current thread to avoid half of the thread creation cuz there is no difference in doing so. We expect this can make the thread-creation error less often, even though we can't gurantee it from happening again. Considering this is a trivial change with positive impact, it's still worth landing and monitor if it's enough to solve the problem in reality.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9281
Test Plan:
Before the change, repeating the test 200 times with 200 workers failed
`~/gtest-parallel/gtest-parallel -r 200 -w 200 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1`
```
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest
[ RUN ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
..unknown file: Failure
C++ exception with description "Resource temporarily unavailable" thrown in the test body.
[ FAILED ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1, where GetParam() = (false, true, 1, 0, 1, 20) (11882 ms)
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest (11882 ms total)
[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (11882 ms total)
[ PASSED ] 0 tests.
[ FAILED ] 1 test, listed below:
[ FAILED ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1, where GetParam() = (false, true, 1, 0, 1, 20)
```
After the change: repeating the test 200 times with 200 workers didn't fail, even with repeating the "repeating" for 10 times like below
`for i in {1..10}; do ~/gtest-parallel/gtest-parallel -r 200 -w 200 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1; done`
```
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[200/200] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
```
It does failed when repeating the test 400 times with 400 workers
`~/project$ ~/gtest-parallel/gtest-parallel -r 400 -w 400 ./write_prepared_transaction_test --gtest_filter=TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1`
```
[1/400] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1 (2928 ms)
Note: Google Test filter = TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest
[ RUN ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1
unknown file: Failure
C++ exception with description "std::bad_alloc" thrown in the test body.
[ FAILED ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/1, where GetParam() = (false, true, 1, 0, 1, 20) (2597 ms)
[----------] 1 test from TwoWriteQueues/SnapshotConcurrentAccessTest (2597 ms total)
```
Reviewed By: ajkr
Differential Revision: D33026776
Pulled By: hx235
fbshipit-source-id: 509f57126392821e835e48396e5bf224f4f5dcac
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9266
This diff adds a new tag `CommitWithTimestamp`. Currently, there is no API to trigger writing
this tag to WAL, thus it is unavailable to users.
This is an ongoing effort to add user-defined timestamp support to write-committed transactions.
This diff also indicates all column families that may potentially participate in the same
transaction must either disable timestamp or have the same timestamp format, since
`CommitWithTimestamp` tag is followed by a single byte-array denoting the commit
timestamp of the transaction. We will enforce this checking in a future diff. We keep this
diff small.
Reviewed By: ltamasi
Differential Revision: D31721350
fbshipit-source-id: e1450811443647feb6ca01adec4c8aaae270ffc6
Summary:
This changes write_prepared_transaction_test under CircleCI to
print a stack trace on unhandled exception, so that we can debug rare
exceptions seen in CircleCI:
[ RUN ] TwoWriteQueues/SnapshotConcurrentAccessTest.SnapshotConcurrentAccess/24
.......unknown file: Failure
C++ exception with description "Resource temporarily unavailable" thrown in the test body.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9276
Test Plan:
manual run test with seeded 'throw', with and without
CIRCLECI=true environment variable
Reviewed By: ajkr, hx235
Differential Revision: D32996993
Pulled By: pdillinger
fbshipit-source-id: e790408ce204b676d3d84a290e41be511b203bfa
Summary:
You could easily reproduce the failure by injecting sleep(11)
before `store.Flush()`. Fixed by setting TTL time to approximately test
timeout time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9226
Test Plan: manual
Reviewed By: akankshamahajan15
Differential Revision: D32698105
Pulled By: pdillinger
fbshipit-source-id: 40529af9d9f2389585988b7c81dffb120e2795a2
Summary:
**Context:**
Some existing internal calls of `GenericRateLimiter::Request()` in backupable_db.cc and newly added internal calls in https://github.com/facebook/rocksdb/pull/8722/ do not make sure `bytes <= GetSingleBurstBytes()` as required by rate_limiter https://github.com/facebook/rocksdb/blob/master/include/rocksdb/rate_limiter.h#L47.
**Impacts of this bug include:**
(1) In debug build, when `GenericRateLimiter::Request()` requests bytes greater than `GenericRateLimiter:: kMinRefillBytesPerPeriod = 100` byte, process will crash due to assertion failure. See https://github.com/facebook/rocksdb/pull/9063#discussion_r737034133 and for possible scenario
(2) In production build, although there will not be the above crash due to disabled assertion, the bug can lead to a request of small bytes being blocked for a long time by a request of same priority with insanely large bytes from a different thread. See updated https://github.com/facebook/rocksdb/wiki/Rate-Limiter ("Notice that although....the maximum bytes that can be granted in a single request have to be bounded...") for more info.
There is an on-going effort to move rate-limiting to file wrapper level so rate limiting in `BackupEngine` and this PR might be made obsolete in the future.
**Summary:**
- Implemented loop-calling `GenericRateLimiter::Request()` with `bytes <= GetSingleBurstBytes()` as a static private helper function `BackupEngineImpl::LoopRateLimitRequestHelper`
-- Considering make this a util function in `RateLimiter` later or do something with `RateLimiter::RequestToken()`
- Replaced buggy internal callers with this helper function wherever requested byte is not pre-limited by `GetSingleBurstBytes()`
- Removed the minimum refill bytes per period enforced by `GenericRateLimiter` since it is useless and prevents testing `GenericRateLimiter` for extreme case with small refill bytes per period.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9063
Test Plan:
- Added a new test that failed the assertion before this change and now passes
- It exposed bugs in [the write during creation in `CopyOrCreateFile()`](df7cc66e17/utilities/backupable/backupable_db.cc (L2034-L2043)), [the read of table properties in `GetFileDbIdentities()`](df7cc66e17/utilities/backupable/backupable_db.cc (L2372-L2378)), [some read of metadata in `BackupMeta::LoadFromFile()`](df7cc66e17/utilities/backupable/backupable_db.cc (L2726))
- Passing Existing tests
Reviewed By: ajkr
Differential Revision: D31824535
Pulled By: hx235
fbshipit-source-id: d2b3dea7a64e2a4b1e6a59fca322f0800a4fcbcc
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9162
Existing TransactionUtil::CheckKeyForConflict() performs only seq-based
conflict checking. If user-defined timestamp is enabled, it should perform
conflict checking based on timestamps too.
Update TransactionUtil::CheckKey-related methods to verify the timestamp of the
latest version of a key is smaller than the read timestamp. Note that
CheckKeysForConflict() is not updated since it's used only by optimistic
transaction, and we do not plan to update it in this upcoming batch of diffs.
Existing GetLatestSequenceForKey() returns the sequence of the latest
version of a specific user key. Since we support user-defined timestamp, we
need to update this method to also return the timestamp (if enabled) of the
latest version of the key. This will be needed for snapshot validation.
Reviewed By: ltamasi
Differential Revision: D31567960
fbshipit-source-id: 2e4a14aed267435a9aa91bc632d2411c01946d44
Summary:
The individual commits in this PR should be self-explanatory.
All small and _very_ low-priority changes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5896
Reviewed By: riversand963
Differential Revision: D18065108
Pulled By: mrambacher
fbshipit-source-id: 236b1a1d9d21f982cc08aa67027108dde5eaf280
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9105
The user contract of SingleDelete is that: a SingleDelete can only be issued to
a key that exists and has NOT been updated. For example, application can insert
one key `key`, and uses a SingleDelete to delete it in the future. The `key`
cannot be updated or removed using Delete.
In reality, especially when write-prepared transaction is being used, things
can get tricky. For example, a prepared transaction already writes `key` to the
memtable after a successful Prepare(). Afterwards, should the transaction
rollback, it will insert a Delete into the memtable to cancel out the prior
Put. Consider the following sequence of operations.
```
// operation sequence 1
Begin txn
Put(key)
Prepare()
Flush()
Rollback txn
Flush()
```
There will be two SSTs resulting from above. One of the contains a PUT, while
the second one contains a Delete. It is also known that releasing a snapshot
can lead to an L0 containing only a SD for a particular key. Consider the
following operations following the above block.
```
// operation sequence 2
db->Put(key)
db->SingleDelete(key)
Flush()
```
The operation sequence 2 can result in an L0 with only the SD.
Should there be a snapshot for conflict checking created before operation
sequence 1, then an attempt to compact the db may hit the assertion failure
below, because ikey_.type is Delete (from a rollback).
```
else if (clear_and_output_next_key_) {
assert(ikey_.type == kTypeValue || ikey_.type == kTypeBlobIndex);
}
```
To fix the assertion failure, we can skip the SingleDelete if we detect an
earlier Delete in the same snapshot interval.
Reviewed By: ltamasi
Differential Revision: D32056848
fbshipit-source-id: 23620a91e28562d91c45cf7e95f414b54b729748
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9060
RocksDB bottommost level compaction may zero out an internal key's sequence if
the key's sequence is in the earliest_snapshot.
In write-prepared transaction, checking the visibility of a certain sequence in
a specific released snapshot may return a "snapshot released" result.
Therefore, it is possible, after a certain sequence of events, a PUT has its
sequence zeroed out, but a subsequent SingleDelete of the same key will still
be output with its original sequence. This violates the ascending order of
keys and leads to incorrect result.
The solution is to use an extra variable `last_key_seq_zeroed_` to track the
information about visibility in earliest snapshot. With this variable, we can
know for sure that a SingleDelete is in the earliest snapshot even if the said
snapshot is released during compaction before processing the SD.
Reviewed By: ltamasi
Differential Revision: D31813016
fbshipit-source-id: d8cff59d6f34e0bdf282614034aaea99be9174e1
Summary:
Directory fsync might be expensive on btrfs and it may not be needed.
Here are 4 directory fsync cases:
1. creating a new file: dir-fsync is not needed on btrfs, as long as the
new file itself is synced.
2. renaming a file: dir-fsync is not needed if the renamed file is
synced. So an API `FsyncAfterFileRename(filename, ...)` is provided
to sync the file on btrfs. By default, it just calls dir-fsync.
3. deleting files: dir-fsync is forced by set
`IOOptions.force_dir_fsync = true`
4. renaming multiple files (like backup and checkpoint): dir-fsync is
forced, the same as above.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8903
Test Plan: run tests on btrfs and non btrfs
Reviewed By: ajkr
Differential Revision: D30885059
Pulled By: jay-zhuang
fbshipit-source-id: dd2730b31580b0bcaedffc318a762d7dbf25de4a
Summary:
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9061
In write-prepared txn, checking a sequence's visibility in a released (old)
snapshot may return "Snapshot released". Suppose we have two snapshots:
```
earliest_snap < earliest_write_conflict_snap
```
If we release `earliest_write_conflict_snap` but keep `earliest_snap` during
bottommost level compaction, then it is possible that certain sequence of
events can lead to a PUT being seq-zeroed followed by a SingleDelete of the
same key. This violates the ascending order of keys, and will cause data
inconsistency.
Reviewed By: ltamasi
Differential Revision: D31813017
fbshipit-source-id: dc68ba2541d1228489b93cf3edda5f37ed06f285
Summary:
This feature was not part of any common or CI build, so no
surprise it broke. Now we can at least ensure compilation. I don't know
how to run the test successfully (missing config file) so it is bypassed
for now.
Fixes https://github.com/facebook/rocksdb/issues/9078
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9088
Test Plan: CI
Reviewed By: mrambacher
Differential Revision: D32009467
Pulled By: pdillinger
fbshipit-source-id: 3e0d1e5fde7f0ece703d48a81479e1cc7392c25c
Summary:
This PR adds support for building on s390x including updating travis CI. It uses the previous work in https://github.com/facebook/rocksdb/pull/6168 and adds some more changes to get all current tests (make check and jni tests) to pass. The tests were run with snappy, lz4, bzip2 and zstd all compiled in.
There are a few pieces still needed to get the travis build working that I don't think I can do. adamretter is this something you could help with?
1. A prebuilt https://rocksdb-deps.s3-us-west-2.amazonaws.com/cmake/cmake-3.14.5-Linux-s390x.deb package
2. A https://hub.docker.com/r/evolvedbinary/rocksjava s390x image
Not sure if there is more required for travis. Happy to help in any way I can.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8962
Reviewed By: mrambacher
Differential Revision: D31802198
Pulled By: pdillinger
fbshipit-source-id: 683511466fa6b505f85ba5a9964a268c6151f0c2
Summary:
New classes FileStorageInfo and LiveFileStorageInfo and
'experimental' function DB::GetLiveFilesStorageInfo, which is intended
to largely replace several fragmented DB functions needed to create
checkpoints and backups.
This function is now used to create checkpoints and backups, because
it fixes many (probably not all) of the prior complexities of checkpoint
not having atomic access to DB metadata. This also ensures strong
functional test coverage of the new API. Specifically, much of the old
CheckpointImpl::CreateCustomCheckpoint has been migrated to and
updated in DBImpl::GetLiveFilesStorageInfo, with the former now
calling the latter.
Also, the class FileStorageInfo in metadata.h compatibly replaces
BackupFileInfo and serves as a new base class for SstFileMetaData.
Some old fields of SstFileMetaData are still provided (for now) but
deprecated.
Although FileStorageInfo::directory is accurate when using db_paths
and/or cf_paths, these have never been supported by Checkpoint
nor BackupEngine and still are not. This change does now detect
these cases and return NotSupported when appropriate. (More work
needed for support.)
Somehow this change broke ProgressCallbackDuringBackup, but
the progress_callback logic was dubious to begin with because it
would call the callback based on copy buffer size, not size actually
copied. Logic and test updated to track size actually copied
per-thread.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8968
Test Plan:
tests updated.
DB::GetLiveFilesStorageInfo mostly tested by use in CheckpointImpl.
DBTest.SnapshotFiles updated to also test GetLiveFilesStorageInfo,
including reading the data after DB close.
Added CheckpointTest.CheckpointWithDbPath (NotSupported).
Reviewed By: siying
Differential Revision: D31242045
Pulled By: pdillinger
fbshipit-source-id: b183d1ce9799e220daaefd6b3b5365d98de676c0
Summary:
`FaultInjectionTest{Env,FS}::ReopenWritableFile()` functions were accidentally deleting WALs from previous `db_stress` runs causing verification to fail. They were operating under the assumption that `ReopenWritableFile()` would delete any existing file. It was a reasonable assumption considering the `{Env,FileSystem}::ReopenWritableFile()` documentation stated that would happen. The only problem was neither the implementations we offer nor the "real" clients in RocksDB code followed that contract. So, this PR updates the contract as well as fixing the fault injection client usage.
The fault injection change exposed that `ExternalSSTFileBasicTest.SyncFailure` was relying on a fault injection `Env` dropping unsynced data written by a regular `Env`. I changed that test to make its `SstFileWriter` use fault injection `Env`, and also implemented `LinkFile()` in fault injection so the unsynced data is tracked under the new name.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8995
Test Plan:
- Verified it fixes the following failure:
```
$ ./db_stress --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/rocksdb_crashtest_whitebox --delpercent=5 --expected_values_dir=/dev/shm/rocksdb_crashtest_expected --iterpercent=0 --key_len_percent_dist=1,30,69 --max_key=100000 --max_key_len=3 --nooverwritepercent=1 --ops_per_thread=1000 --prefixpercent=0 --readpercent=60 --reopen=0 --target_file_size_base=1048576 --test_batches_snapshots=0 --write_buffer_size=1048576 --writepercent=35 --value_size_mult=33 -threads=1
...
$ ./db_stress --avoid_flush_during_recovery=1 --clear_column_family_one_in=0 --column_families=1 --db=/dev/shm/rocksdb_crashtest_whitebox --delpercent=5 --destroy_db_initially=0 --expected_values_dir=/dev/shm/rocksdb_crashtest_expected --iterpercent=10 --key_len_percent_dist=1,30,69 --max_bytes_for_level_base=4194304 --max_key=100000 --max_key_len=3 --nooverwritepercent=1 --open_files=-1 --open_metadata_write_fault_one_in=8 --open_write_fault_one_in=16 --ops_per_thread=1000 --prefix_size=-1 --prefixpercent=0 --readpercent=50 --sync=1 --target_file_size_base=1048576 --test_batches_snapshots=0 --write_buffer_size=1048576 --writepercent=35 --value_size_mult=33 -threads=1
...
Verification failed for column family 0 key 000000000000001300000000000000857878787878 (1143): Value not found: NotFound:
Crash-recovery verification failed :(
...
```
- `make check -j48`
Reviewed By: ltamasi
Differential Revision: D31495388
Pulled By: ajkr
fbshipit-source-id: 7886ccb6a07cb8b78ad7b6c1c341ccf40bb68385
Summary:
Background: Cache warming up will cause potential read performance degradation due to reading blocks from storage to the block cache. Since in production, the workload and access pattern to a certain DB is stable, it is a potential solution to dump out the blocks belonging to a certain DB to persist storage (e.g., to a file) and bulk-load the blocks to Secondary cache before the DB is relaunched. For example, when migrating a DB form host A to host B, it will take a short period of time, the access pattern to blocks in the block cache will not change much. It is efficient to dump out the blocks of certain DB, migrate to the destination host and insert them to the Secondary cache before we relaunch the DB.
Design: we introduce the interface of CacheDumpWriter and CacheDumpRead for user to store the blocks dumped out from block cache. RocksDB will encode all the information and send the string to the writer. User can implement their own writer it they want. CacheDumper and CacheLoad are introduced to save the blocks and load the blocks respectively.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8912
Test Plan: add new tests to lru_cache_test and pass make check.
Reviewed By: pdillinger
Differential Revision: D31452871
Pulled By: zhichao-cao
fbshipit-source-id: 11ab4f5d03e383f476947116361d54188d36ec48
Summary:
This header file was including everything and the kitchen sink when it did not need to. This resulted in many places including this header when they needed other pieces instead.
Cleaned up this header to only include what was needed and fixed up the remaining code to include what was now missing.
Hopefully, this sort of code hygiene cleanup will speed up the builds...
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8930
Reviewed By: pdillinger
Differential Revision: D31142788
Pulled By: mrambacher
fbshipit-source-id: 6b45de3f300750c79f751f6227dece9cfd44085d
Summary:
Right now FaultInjectionTestFS::InjectThreadSpecificReadError() might try to corrupt return bytes, but these bytes might be from mmapped files, which would cause segfault. Instead FaultInjectionTestFS::InjectThreadSpecificReadError() should never corrupt data unless it is in caller's buffer.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8952
Test Plan: See db_stress still runs and make sure in a test run failurs are still injected in non-mmap cases.
Reviewed By: ajkr, ltamasi
Differential Revision: D31147318
fbshipit-source-id: 9484a64ff2aaa36685557203f449286e694e65f9
Summary:
There is a corner case when using WriteUnprepared transactions when
`WriteUnpreparedTxn::Get` returns `Status::TryAgain` instead of
propagating the result of `GetFromBatchAndDB`. The patch adds
`PermitUncheckedError` to make the `ASSERT_STATUS_CHECKED` build pass in
this case as well.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8947
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D31125422
Pulled By: ltamasi
fbshipit-source-id: 42de51dcfa9384e032244c2b4d3f40e9a4111194
Summary:
Several improvements to MultiRead:
1. Fix a bug in stress test which causes false positive when both MultiRead() return and individual read request have failure injected.
2. Add two more types of fault that should be handled: empty read results and checksum mismatch
3. Add a message indicating which type of fault is injected
4. Increase the failure rate
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8937
Reviewed By: anand1976
Differential Revision: D31085930
fbshipit-source-id: 3a04994a3cadebf9a64d25e1fe12b14b7a272fba
Summary:
Updates a few remaining functions that should have been updated
from Status -> IOStatus, and adds to HISTORY for the overall change
including https://github.com/facebook/rocksdb/issues/8820.
This change is for inclusion in version 6.25.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8940
Test Plan: CI
Reviewed By: zhichao-cao
Differential Revision: D31085029
Pulled By: pdillinger
fbshipit-source-id: 91557c6a39ef1d90357d4f4dcd79af0645d87c7b
Summary:
Right now, the failure injection test for MultiGet() is not sufficient. Improve it with TestFSRandomAccessFile::MultiRead() injecting failures.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8925
Test Plan: Run crash test locally for a while.
Reviewed By: anand1976
Differential Revision: D31000529
fbshipit-source-id: 439c7e02cf7440ac5af82deb609e202abdca3e1f
Summary:
In order to populate the IOStatus up to the higher level, replace some of the Status to IOStatus.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8820
Test Plan: make check
Reviewed By: pdillinger
Differential Revision: D30967215
Pulled By: zhichao-cao
fbshipit-source-id: ccf9d5cfbd9d3de047c464aaa85f9fa43b474903
Summary:
This allows the wrapper classes to own the wrapped object and eliminates confusion as to ownership. Previously, many classes implemented their own ownership solutions. Fixes https://github.com/facebook/rocksdb/issues/8606
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8618
Reviewed By: pdillinger
Differential Revision: D30136064
Pulled By: mrambacher
fbshipit-source-id: d0bf471df8818dbb1770a86335fe98f761cca193
Summary:
It's always annoying to find a header does not include its own
dependencies and only works when included after other includes. This
change adds `make check-headers` which validates that each header can
be included at the top of a file. Some headers are excluded e.g. because
of platform or external dependencies.
rocksdb_namespace.h had to be re-worked slightly to enable checking for
failure to include it. (ROCKSDB_NAMESPACE is a valid namespace name.)
Fixes mostly involve adding and cleaning up #includes, but for
FileTraceWriter, a constructor was out-of-lined to make a forward
declaration sufficient.
This check is not currently run with `make check` but is added to
CircleCI build-linux-unity since that one is already relatively fast.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8893
Test Plan: existing tests and resolving issues detected by new check
Reviewed By: mrambacher
Differential Revision: D30823300
Pulled By: pdillinger
fbshipit-source-id: 9fff223944994c83c105e2e6496d24845dc8e572
Summary:
ManagedObjects are shared pointer objects where RocksDB wants to share a single object between multiple configurations. For example, the Cache may be shared between multiple column families/tables or the Statistics may be shared between multiple databases.
ManagedObjects are stored in the ObjectRegistry by Type (e.g. Cache) and ID. For a given type/ID name, a single object is stored.
APIs were added to get/set/create these objects.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8658
Reviewed By: pdillinger
Differential Revision: D30806273
Pulled By: mrambacher
fbshipit-source-id: 832ac4423b210c4c4b4a456b35897334775d3160
Summary:
Context:
While all the non-trivial write operations in BackupEngine go through the RateLimiter, reads currently do not. In general, this is not a huge issue because (especially since some I/O efficiency fixes) reads in BackupEngine are mostly limited by corresponding writes, for both backup and restore. But in principle we should charge the RateLimiter for reads as well.
- Charged read operations in `BackupEngineImpl::CopyOrCreateFile`, `BackupEngineImpl::ReadFileAndComputeChecksum`, `BackupEngineImpl::BackupMeta::LoadFromFile` and `BackupEngineImpl::GetFileDbIdentities`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8722
Test Plan:
- Passed existing tests
- Passed added unit tests
Reviewed By: pdillinger
Differential Revision: D30610464
Pulled By: hx235
fbshipit-source-id: 9b08c9387159a5385c8d390d6666377a0d0117e5
Summary:
A "LATEST_BACKUP" file was left in the backup directory by
"BackupEngineTest.NoDeleteWithReadOnly" test, affecting future test
runs. In particular, it caused "BackupEngineTest.IOStats" to fail since
it relies on backup directory containing only data written by its
`BackupEngine`.
The fix is to promote "LATEST_BACKUP" to an explicitly managed file so
it is deleted in `BackupEngineTest` constructor if it exists.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8887
Test Plan:
below command used to fail. Now it passes:
```
$ TEST_TMPDIR=/dev/shm ./backupable_db_test --gtest_filter='BackupEngineTest.NoDeleteWithReadOnly:BackupEngineTest.IOStats'
```
Reviewed By: pdillinger
Differential Revision: D30812336
Pulled By: ajkr
fbshipit-source-id: 32dfbe1368ebdab872e610764bfea5daf9a2af09
