Summary:
**Context:**
Current `NonBatchedOpsStressTest` does not allow multi-thread read (i.e, Get, Iterator) and write (i.e, Put, Merge) or delete to the same key. Every read or write/delete operation will acquire lock (`GetLocksForKeyRange`) on the target key to gain exclusive access to it. This does not align with RocksDB's nature of allowing multi-thread read and write/delete to the same key, that is concurrent threads can issue read/write/delete to RocksDB without external locking. Therefore this is a gap in our testing coverage.
To close the gap, biggest challenge remains in verifying db value against expected state in presence of parallel read and write/delete. The challenge is due to read/write/delete to the db and read/write to expected state is not within one atomic operation. Therefore we may not know the exact expected state of a certain db read, as by the time we read the expected state for that db read, another write to expected state for another db write to the same key might have changed the expected state.
**Summary:**
Credited to ajkr's idea, we now solve this challenge by breaking the 32-bits expected value of a key into different parts that can be read and write to in parallel.
Basically we divide the 32-bits expected value into `value_base` (corresponding to the previous whole 32 bits but now with some shrinking in the value base range we allow), `pending_write` (i.e, whether there is an ongoing concurrent write), `del_counter` (i.e, number of times a value has been deleted, analogous to value_base for write), `pending_delete` (similar to pending_write) and `deleted` (i.e whether a key is deleted).
Also, we need to use incremental `value_base` instead of random value base as before because we want to control the range of value base a correct db read result can possibly be in presence of parallel read and write. In that way, we can verify the correctness of the read against expected state more easily. This is at the cost of reducing the randomness of the value generated in NonBatchedOpsStressTest we are willing to accept.
(For detailed algorithm of how to use these parts to infer expected state of a key, see the PR)
Misc: hide value_base detail from callers of ExpectedState by abstracting related logics into ExpectedValue class
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11058
Test Plan:
- Manual test of small number of keys (i.e, high chances of parallel read and write/delete to same key) with equally distributed read/write/deleted for 30 min
```
python3 tools/db_crashtest.py --simple {blackbox|whitebox} --sync_fault_injection=1 --skip_verifydb=0 --continuous_verification_interval=1000 --clear_column_family_one_in=0 --max_key=10 --column_families=1 --threads=32 --readpercent=25 --writepercent=25 --nooverwritepercent=0 --iterpercent=25 --verify_iterator_with_expected_state_one_in=1 --num_iterations=5 --delpercent=15 --delrangepercent=10 --range_deletion_width=5 --use_merge={0|1} --use_put_entity_one_in=0 --use_txn=0 --verify_before_write=0 --user_timestamp_size=0 --compact_files_one_in=1000 --compact_range_one_in=1000 --flush_one_in=1000 --get_property_one_in=1000 --ingest_external_file_one_in=100 --backup_one_in=100 --checkpoint_one_in=100 --approximate_size_one_in=0 --acquire_snapshot_one_in=100 --use_multiget=0 --prefixpercent=0 --get_live_files_one_in=1000 --manual_wal_flush_one_in=1000 --pause_background_one_in=1000 --target_file_size_base=524288 --write_buffer_size=524288 --verify_checksum_one_in=1000 --verify_db_one_in=1000
```
- Rehearsal stress test for normal parameter and aggressive parameter to see if such change can find what existing stress test can find (i.e, no regression in testing capability)
- [Ongoing]Try to find new bugs with this change that are not found by current NonBatchedOpsStressTest with no parallel read and write/delete to same key
Reviewed By: ajkr
Differential Revision: D42257258
Pulled By: hx235
fbshipit-source-id: e6fdc18f1fad3753e5ac91731483a644d9b5b6eb
Summary:
When the DB is opened, RocksDB creates a temp OPTIONS file, writes the current options to it, and renames it. In case of a failure, the temp file is left behind, and is not deleted by PurgeObsoleteFiles(). Fix this by explicitly deleting the temp file if writing to it or renaming it fails.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11423
Test Plan: Add a unit test
Reviewed By: akankshamahajan15
Differential Revision: D45540454
Pulled By: anand1976
fbshipit-source-id: 47facdc30d8cc5667036312d04b21d3fc253c92e
Summary:
Added a ticker stat, `BLOCK_CHECKSUM_MISMATCH_COUNT`, to count how many block checksum verifications detected a mismatch.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11438
Test Plan: new unit test
Reviewed By: pdillinger
Differential Revision: D45788179
Pulled By: ajkr
fbshipit-source-id: e2b44eba7c23b3e110ebe69eaa78a710dec2590f
Summary:
This patch adds support to write and read a user-defined timestamp size record in log writer and log reader. It will be used by WAL logs to persist the user-defined timestamp format for subsequent WriteBatch records. Reading and writing UDT sizes for WAL logs are not included in this patch. It will be in a follow up.
The syntax for the record is: at write time, one such record is added when log writer encountered any non-zero UDT size it hasn't recorded so far. At read time, all such records read up to a point are accumulated and applicable to all subsequent WriteBatch records.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11433
Test Plan:
```
make clean && make -j32 all
./log_test --gtest_filter="*WithTimestampSize*"
```
Reviewed By: ltamasi
Differential Revision: D45678708
Pulled By: jowlyzhang
fbshipit-source-id: b770c8f45bb7b9383b14aac9f22af781304fb41d
Summary:
- Add a new option `CompactionOptionsFIFO::file_temperature_age_thresholds` that allows user to specify age thresholds for compacting files to different temperatures. File temperature can be used to store files in different storage media. The new options allows specifying multiple temperature-age pairs. The option uses struct for a temperature-age pair to use the existing parsing functionality to make the option dynamically settable.
- Deprecate the old option `age_for_warm` that was added for a similar purpose.
- Compaction score calculation logic is updated to check if a file needs to be compacted to change its temperature.
- Some refactoring is done in `FIFOCompactionPicker::PickTemperatureChangeCompaction`.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11428
Test Plan: adapted unit tests that were for `age_for_warm` to this new option.
Reviewed By: ajkr
Differential Revision: D45611412
Pulled By: cbi42
fbshipit-source-id: 2dc384841f61cc04abb9681e31aa2de0f0b06106
Summary:
Context:
This pull request update is in response to a comment made on https://github.com/facebook/rocksdb/pull/8596#discussion_r680264932. The current implementation of RefillBytesAndGrantRequestsLocked() drains all available_bytes, but the first request after the last wave of requesting/bytes granting is done is not being handled in the same way.
This creates a scenario where if a request for a large amount of bytes is enqueued first, but there are not enough available_bytes to fulfill it, the request is put to sleep until the next refill time. Meanwhile, a later request for a smaller number of bytes comes in and is granted immediately. This behavior is not fair as the earlier request was made first.
To address this issue, we have made changes to the code to exhaust the remaining available bytes from the request and queue the remaining. With this change, requests are granted in the order they are received, ensuring that earlier requests are not unfairly delayed by later, smaller requests. The specific scenario described above will no longer occur with this change. Also consolidated `granted` and `request_bytes` as part of the change since `granted` is equivalent to `request_bytes == 0`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11425
Test Plan: Added `AvailableByteSizeExhaustTest`
Reviewed By: hx235
Differential Revision: D45570711
Pulled By: jaykorean
fbshipit-source-id: a7117ed17bf4b8a7ae0f76124cb41902db1a2592
Summary:
**Background** - runtime detection of certain x86 CPU features was added for optimizing CRC32c checksums, where performance is dramatically affected by the availability of certain CPU instructions and code using intrinsics for those instructions. And Java builds with native library try to be broadly compatible but performant.
What has changed is that CRC32c is no longer the most efficient cheecksum on contemporary x86_64 hardware, nor the default checksum. XXH3 is generally faster and not as dramatically impacted by the availability of certain CPU instructions. For example, on my Skylake system using db_bench (similar on an older Skylake system without AVX512):
PORTABLE=1 empty USE_SSE : xxh3->8 GB/s crc32c->0.8 GB/s (no SSE4.2 nor AVX2 instructions)
PORTABLE=1 USE_SSE=1 : xxh3->19 GB/s crc32c->16 GB/s (with SSE4.2 and AVX2)
PORTABLE=0 USE_SSE ignored: xxh3->28 GB/s crc32c->16 GB/s (also some AVX512)
Testing a ~10 year old system, with SSE4.2 but without AVX2, crc32c is a similar speed to the new systems but xxh3 is only about half that speed, also 8GB/s like the non-AVX2 compile above. Given that xxh3 has specific optimization for AVX2, I think we can infer that that crc32c is only fastest for that ~2008-2013 period when SSE4.2 was included but not AVX2. And given that xxh3 is only about 2x slower on these systems (not like >10x slower for unoptimized crc32c), I don't think we need to invest too much in optimally adapting to these old cases.
x86 hardware that doesn't support fast CRC32c is now extremely rare, so requiring a custom build to support such hardware is fine IMHO.
**This change** does two related things:
* Remove runtime CPU detection for optimizing CRC32c on x86. Maintaining this code is non-zero work, and compiling special code that doesn't work on the configured target instruction set for code generation is always dubious. (On the one hand we have to ensure the CRC32c code uses SSE4.2 but on the other hand we have to ensure nothing else does.)
* Detect CPU features in source code, not in build scripts. Although there are some hypothetical advantages to detectiong in build scripts (compiler generality), RocksDB supports at least three build systems: make, cmake, and buck. It's not practical to support feature detection on all three, and we have suffered from missed optimization opportunities by relying on missing or incomplete detection in cmake and buck. We also depend on some components like xxhash that do source code detection anyway.
**In more detail:**
* `HAVE_SSE42`, `HAVE_AVX2`, and `HAVE_PCLMUL` replaced by standard macros `__SSE4_2__`, `__AVX2__`, and `__PCLMUL__`.
* MSVC does not provide high fidelity defines for SSE, PCLMUL, or POPCNT, but we can infer those from `__AVX__` or `__AVX2__` in a compatibility header. In rare cases of false negative or false positive feature detection, a build engineer should be able to set defines to work around the issue.
* `__POPCNT__` is another standard define, but we happen to only need it on MSVC, where it is set by that compatibility header, or can be set by the build engineer.
* `PORTABLE` can be set to a CPU type, e.g. "haswell", to compile for that CPU type.
* `USE_SSE` is deprecated, now equivalent to PORTABLE=haswell, which roughly approximates its old behavior.
Notably, this change should enable more builds to use the AVX2-optimized Bloom filter implementation.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11419
Test Plan:
existing tests, CI
Manual performance tests after the change match the before above (none expected with make build).
We also see AVX2 optimized Bloom filter code enabled when expected, by injecting a compiler error. (Performance difference is not big on my current CPU.)
Reviewed By: ajkr
Differential Revision: D45489041
Pulled By: pdillinger
fbshipit-source-id: 60ceb0dd2aa3b365c99ed08a8b2a087a9abb6a70
Summary:
See motivation and description in new ShardedCacheOptions::hash_seed option.
Updated db_bench so that its seed param is used for the cache hash seed.
Made its code more safe to ensure seed is set before use.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11391
Test Plan:
unit tests added / updated
**Performance** - no discernible difference seen running cache_bench repeatedly before & after. With lru_cache and hyper_clock_cache.
Reviewed By: hx235
Differential Revision: D45557797
Pulled By: pdillinger
fbshipit-source-id: 40bf4da6d66f9d41a8a0eb8e5cf4246a4aa07934
Summary:
Fix build error: variable 'base_level' may be uninitialized
```
db_impl_compaction_flush.cc:1195:21: error: variable 'base_level' may be uninitialized when used here [-Werror,-Wconditional-uninitialized]
level = base_level;
```
^~~~~~~~~~
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11435
Test Plan: CircleCI jobs
Reviewed By: cbi42
Differential Revision: D45708176
Pulled By: akankshamahajan15
fbshipit-source-id: 851b1205b22b63d728495e5735fa91b0ad8e012b
Summary:
**Context:**
We prefetch the tail part of a SST file (i.e, the blocks after data blocks till the end of the file) during each SST file open in hope to prefetch all the stuff at once ahead of time for later read e.g, footer, meta index, filter/index etc. The existing approach to estimate the tail size to prefetch is through `TailPrefetchStats` heuristics introduced in https://github.com/facebook/rocksdb/pull/4156, which has caused small reads in unlucky case (e.g, small read into the tail buffer during table open in thread 1 under the same BlockBasedTableFactory object can make thread 2's tail prefetching use a small size that it shouldn't) and is hard to debug. Therefore we decide to record the exact tail size and use it directly to prefetch tail of the SST instead of relying heuristics.
**Summary:**
- Obtain and record in manifest the tail size in `BlockBasedTableBuilder::Finish()`
- For backward compatibility, we fall back to TailPrefetchStats and last to simple heuristics that the tail size is a linear portion of the file size - see PR conversation for more.
- Make`tail_start_offset` part of the table properties and deduct tail size to record in manifest for external files (e.g, file ingestion, import CF) and db repair (with no access to manifest).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11406
Test Plan:
1. New UT
2. db bench
Note: db bench on /tmp/ where direct read is supported is too slow to finish and the default pinning setting in db bench is not helpful to profile # sst read of Get. Therefore I hacked the following to obtain the following comparison.
```
diff --git a/table/block_based/block_based_table_reader.cc b/table/block_based/block_based_table_reader.cc
index bd5669f0f..791484c1f 100644
--- a/table/block_based/block_based_table_reader.cc
+++ b/table/block_based/block_based_table_reader.cc
@@ -838,7 +838,7 @@ Status BlockBasedTable::PrefetchTail(
&tail_prefetch_size);
// Try file system prefetch
- if (!file->use_direct_io() && !force_direct_prefetch) {
+ if (false && !file->use_direct_io() && !force_direct_prefetch) {
if (!file->Prefetch(prefetch_off, prefetch_len, ro.rate_limiter_priority)
.IsNotSupported()) {
prefetch_buffer->reset(new FilePrefetchBuffer(
diff --git a/tools/db_bench_tool.cc b/tools/db_bench_tool.cc
index ea40f5fa0..39a0ac385 100644
--- a/tools/db_bench_tool.cc
+++ b/tools/db_bench_tool.cc
@@ -4191,6 +4191,8 @@ class Benchmark {
std::shared_ptr<TableFactory>(NewCuckooTableFactory(table_options));
} else {
BlockBasedTableOptions block_based_options;
+ block_based_options.metadata_cache_options.partition_pinning =
+ PinningTier::kAll;
block_based_options.checksum =
static_cast<ChecksumType>(FLAGS_checksum_type);
if (FLAGS_use_hash_search) {
```
Create DB
```
./db_bench --bloom_bits=3 --use_existing_db=1 --seed=1682546046158958 --partition_index_and_filters=1 --statistics=1 -db=/dev/shm/testdb/ -benchmarks=readrandom -key_size=3200 -value_size=512 -num=1000000 -write_buffer_size=6550000 -disable_auto_compactions=false -target_file_size_base=6550000 -compression_type=none
```
ReadRandom
```
./db_bench --bloom_bits=3 --use_existing_db=1 --seed=1682546046158958 --partition_index_and_filters=1 --statistics=1 -db=/dev/shm/testdb/ -benchmarks=readrandom -key_size=3200 -value_size=512 -num=1000000 -write_buffer_size=6550000 -disable_auto_compactions=false -target_file_size_base=6550000 -compression_type=none
```
(a) Existing (Use TailPrefetchStats for tail size + use seperate prefetch buffer in PartitionedFilter/IndexReader::CacheDependencies())
```
rocksdb.table.open.prefetch.tail.hit COUNT : 3395
rocksdb.sst.read.micros P50 : 5.655570 P95 : 9.931396 P99 : 14.845454 P100 : 585.000000 COUNT : 999905 SUM : 6590614
```
(b) This PR (Record tail size + use the same tail buffer in PartitionedFilter/IndexReader::CacheDependencies())
```
rocksdb.table.open.prefetch.tail.hit COUNT : 14257
rocksdb.sst.read.micros P50 : 5.173347 P95 : 9.015017 P99 : 12.912610 P100 : 228.000000 COUNT : 998547 SUM : 5976540
```
As we can see, we increase the prefetch tail hit count and decrease SST read count with this PR
3. Test backward compatibility by stepping through reading with post-PR code on a db generated pre-PR.
Reviewed By: pdillinger
Differential Revision: D45413346
Pulled By: hx235
fbshipit-source-id: 7d5e36a60a72477218f79905168d688452a4c064
Summary:
Roughly group ReadOptions into those that apply generally and those that only apply to range scans. Also use field assignment idiom to simplify specification of default values.
Also some rearranging to reduce unused padding. sizeof(ReadOptions) was 144 on my system, now 136.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11430
Test Plan: existing tests, no functional change intended
Reviewed By: hx235
Differential Revision: D45626508
Pulled By: pdillinger
fbshipit-source-id: 227d4158c5123405324f273ded2eb9d8bce86364
Summary:
This PR adds a plugin that supports AES-CTR encryption for RocksDB based on highly performant intel open-source cryptographic library IPP-Crypto.
Details:
- supports AES-128, AES-192, and AES-256.
- uses the CTR mode of operation.
- based on the Intel® crypto library -- https://github.com/intel/ipp-crypto.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11429
Reviewed By: cbi42
Differential Revision: D45622342
Pulled By: ajkr
fbshipit-source-id: 2463fa2b8ae625fdd7d83768e274c74e3f2a0f46
Summary:
Document ReadOptions::io_activity as internal-use-only. And to keep kUnknown as last (and why).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11427
Test Plan: comments only
Reviewed By: hx235
Differential Revision: D45576986
Pulled By: pdillinger
fbshipit-source-id: aae15aa22ea91370c2b7366154e45d4b91a79ad2
Summary:
the test is flaky when compiled with `make -j56 COERCE_CONTEXT_SWITCH=1 ./db_universal_compaction_test`. The cause is that a manual compaction `CompactRange()` can finish and return before obsolete files are deleted. One reason for this is that a manual compaction waits until `manual.done` is set here 62fc15f009/db/db_impl/db_impl_compaction_flush.cc (L1978)
and the compaction thread can set `manual.done`:
62fc15f009/db/db_impl/db_impl_compaction_flush.cc (L3672)
and then temporarily release mutex_:
62fc15f009/db/db_impl/db_impl_files.cc (L317)
before purging obsolete files:
62fc15f009/db/db_impl/db_impl_compaction_flush.cc (L3144)
With `COERCE_CONTEXT_SWITCH=1`, `bg_cv_.SignalAll()` is called during `mutex_.Lock()`, so the manual compaction thread can wake up and return before obsolete files are deleted. Updated the test to only count live SST files.
Also updated `FindObsoleteFiles()` to avoid locking a locked mutex.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11412
Test Plan: `make -j56 COERCE_CONTEXT_SWITCH=1 ./db_universal_compaction_test`
Reviewed By: ajkr
Differential Revision: D45342242
Pulled By: cbi42
fbshipit-source-id: 955c9796aa3f484e3557d300f97cffacb3ed9b0c
Summary:
when I use g++-13 to exec the `make all` command, the output throws the warnings.
```
db/compaction/compaction_job_test.cc: In member function ‘void rocksdb::CompactionJobTestBase::AddMockFile(const rocksdb::mock::KVVector&, int)’:
db/compaction/compaction_job_test.cc:376:57: error: redundant move in initialization [-Werror=redundant-move]
376 | env_, GenerateFileName(file_number), std::move(contents)));
| ~~~~~~~~~^~~~~~~~~~
db/compaction/compaction_job_test.cc:375:7: note: in expansion of macro ‘EXPECT_OK’
375 | EXPECT_OK(mock_table_factory_->CreateMockTable(
| ^~~~~~~~~
db/compaction/compaction_job_test.cc:376:57: note: remove ‘std::move’ call
376 | env_, GenerateFileName(file_number), std::move(contents)));
| ~~~~~~~~~^~~~~~~~~~
db/compaction/compaction_job_test.cc:375:7: note: in expansion of macro ‘EXPECT_OK’
375 | EXPECT_OK(mock_table_factory_->CreateMockTable(
| ^~~~~~~~~
cc1plus: all warnings being treated as errors
make: *** [Makefile:2507: db/compaction/compaction_job_test.o] Error 1
```
and I also add some `(void)unused_variable` statements because of the cmake argument `-Wunused-but-set-variable -Wunused-but-set-variable`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11418
Reviewed By: akankshamahajan15
Differential Revision: D45528223
Pulled By: ajkr
fbshipit-source-id: fee1a77c30039a56b481de953f0a834cc788abbc
Summary:
When a DB is opened, RocksDB creates an empty WAL file. When the DB is reopened and the WAL is empty, the min log number to keep is not advanced until a memtable flush happens. If a process crashes soon after reopening the DB, its likely that no memtable flush would have happened, which means the empty WAL file is not deleted. In a crash loop scenario, this leads to empty WAL files accumulating. Fix this by ensuring the min log number is advanced if the WAL is empty.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11409
Test Plan: Add a unit test
Reviewed By: ajkr
Differential Revision: D45281685
Pulled By: anand1976
fbshipit-source-id: 0225877c613e65ffb30972a0051db2830105423e
Summary:
For better clarity, encouraging more options explicitly specified using fields rather than positionally via constructor parameter lists. Simplifies code maintenance as new fields are added. Deprecate some cases of the confusing pattern of NewWhatever() functions returning shared_ptr.
Net reduction of about 70 source code lines (including comments).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11386
Test Plan: existing tests
Reviewed By: ajkr
Differential Revision: D45059075
Pulled By: pdillinger
fbshipit-source-id: d53fa09b268024f9c55254bb973b6c69feebf41a
Summary:
lldb is more supported for Meta infrastructure than gdb, so adding support for it in generating stack traces and attaching debugger on crash. For now you need to set ROCKSDB_LLDB_STACK=1 for stack traces or ROCKSDB_DEBUG=lldb for interactive debugging.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11413
Test Plan: some manual testing (no production code changes)
Reviewed By: ajkr
Differential Revision: D45360952
Pulled By: pdillinger
fbshipit-source-id: 862bc8800eb03e3bdc1be8c0702960a19db45be8
Summary:
Seen in Meta-internal builds that manually depend on rocksdb_whole_archive_lib and want to automatically depend on rocksdb_lib. This change puts rocksdb_lib in the ancestry of rocksdb_whole_archive_lib, and buck2 appears to recognize that even if rocksdb_lib is listed as a separate dependency downstream.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11421
Test Plan: Run failing internal build with the change. See T147085939
Reviewed By: akankshamahajan15
Differential Revision: D45446689
Pulled By: pdillinger
fbshipit-source-id: e8a891fa020dfcf0564b35d30511d70347650fa8
Summary:
The old `StackableDB` based BlobDB implementation relies on a DB listener to track the total size of the SST files in the database and to trigger FIFO eviction. Some test cases in `BlobDBTest` assume that the listener is notified by the time `DB::Flush` returns, which is not guaranteed (side note: `TEST_WaitForFlushMemTable` would not guarantee this either). The patch fixes these tests by using `SyncPoint`s to make sure the listener is actually called before verifying the FIFO behavior.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11417
Test Plan:
```
make -j56 COERCE_CONTEXT_SWITCH=1 blob_db_test
./blob_db_test --gtest_filter=BlobDBTest.FIFOEviction_TriggerOnSSTSizeChange
./blob_db_test --gtest_filter=BlobDBTest.FilterForFIFOEviction
./blob_db_test --gtest_filter=BlobDBTest.FIFOEviction_NoEnoughBlobFilesToEvict
```
Reviewed By: ajkr
Differential Revision: D45407135
Pulled By: ltamasi
fbshipit-source-id: fcd63d76937d2c975f569a6635ce8730772a3d75
Summary:
add option `block_protection_bytes_per_key` and implementation for block per key-value checksum. The main changes are
1. checksum construction and verification in block.cc/h
2. pass the option `block_protection_bytes_per_key` around (mainly for methods defined in table_cache.h)
3. unit tests/crash test updates
Tests:
* Added unit tests
* Crash test: `python3 tools/db_crashtest.py blackbox --simple --block_protection_bytes_per_key=1 --write_buffer_size=1048576`
Follow up (maybe as a separate PR): make sure corruption status returned from BlockIters are correctly handled.
Performance:
Turning on block per KV protection has a non-trivial negative impact on read performance and costs additional memory.
For memory, each block includes additional 24 bytes for checksum-related states beside checksum itself. For CPU, I set up a DB of size ~1.2GB with 5M keys (32 bytes key and 200 bytes value) which compacts to ~5 SST files (target file size 256 MB) in L6 without compression. I tested readrandom performance with various block cache size (to mimic various cache hit rates):
```
SETUP
make OPTIMIZE_LEVEL="-O3" USE_LTO=1 DEBUG_LEVEL=0 -j32 db_bench
./db_bench -benchmarks=fillseq,compact0,waitforcompaction,compact,waitforcompaction -write_buffer_size=33554432 -level_compaction_dynamic_level_bytes=true -max_background_jobs=8 -target_file_size_base=268435456 --num=5000000 --key_size=32 --value_size=200 --compression_type=none
BENCHMARK
./db_bench --use_existing_db -benchmarks=readtocache,readrandom[-X10] --num=5000000 --key_size=32 --disable_auto_compactions --reads=1000000 --block_protection_bytes_per_key=[0|1] --cache_size=$CACHESIZE
The readrandom ops/sec looks like the following:
Block cache size: 2GB 1.2GB * 0.9 1.2GB * 0.8 1.2GB * 0.5 8MB
Main 240805 223604 198176 161653 139040
PR prot_bytes=0 238691 226693 200127 161082 141153
PR prot_bytes=1 214983 193199 178532 137013 108211
prot_bytes=1 vs -10% -15% -10.8% -15% -23%
prot_bytes=0
```
The benchmark has a lot of variance, but there was a 5% to 25% regression in this benchmark with different cache hit rates.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11287
Reviewed By: ajkr
Differential Revision: D43970708
Pulled By: cbi42
fbshipit-source-id: ef98d898b71779846fa74212b9ec9e08b7183940
Summary:
Tweak some bounds and things, and reduce risk of surprise results by running on all supported compressions (mostly).
Also improves the precise compressibility of CompressibleString by using RandomBinaryString.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11396
Test Plan: updated tests
Reviewed By: ltamasi
Differential Revision: D45211938
Pulled By: pdillinger
fbshipit-source-id: 9dc1dd8574a60a9364efe18558be66d31a35598b
Summary:
## Option API updates
* Add new CompressionOptions::max_compressed_bytes_per_kb, which corresponds to 1024.0 / min allowable compression ratio. This avoids the hard-coded minimum ratio of 8/7.
* Remove unnecessary constructor for CompressionOptions.
* Document undocumented CompressionOptions. Use idiom for default values shown clearly in one place (not precariously repeated).
## Stat API updates
* Deprecate the BYTES_COMPRESSED, BYTES_DECOMPRESSED histograms. Histograms incur substantial extra space & time costs compared to tickers, and the distribution of uncompressed data block sizes tends to be uninteresting. If we're interested in that distribution, I don't see why it should be limited to blocks stored as compressed.
* Deprecate the NUMBER_BLOCK_NOT_COMPRESSED ticker, because the name is very confusing.
* New or existing tickers relevant to compression:
* BYTES_COMPRESSED_FROM
* BYTES_COMPRESSED_TO
* BYTES_COMPRESSION_BYPASSED
* BYTES_COMPRESSION_REJECTED
* COMPACT_WRITE_BYTES + FLUSH_WRITE_BYTES (both existing)
* NUMBER_BLOCK_COMPRESSED (existing)
* NUMBER_BLOCK_COMPRESSION_BYPASSED
* NUMBER_BLOCK_COMPRESSION_REJECTED
* BYTES_DECOMPRESSED_FROM
* BYTES_DECOMPRESSED_TO
We can compute a number of things with these stats:
* "Successful" compression ratio: BYTES_COMPRESSED_FROM / BYTES_COMPRESSED_TO
* Compression ratio of data on which compression was attempted: (BYTES_COMPRESSED_FROM + BYTES_COMPRESSION_REJECTED) / (BYTES_COMPRESSED_TO + BYTES_COMPRESSION_REJECTED)
* Compression ratio of data that could be eligible for compression: (BYTES_COMPRESSED_FROM + X) / (BYTES_COMPRESSED_TO + X) where X = BYTES_COMPRESSION_REJECTED + NUMBER_BLOCK_COMPRESSION_REJECTED
* Overall SST compression ratio (compression disabled vs. actual): (Y - BYTES_COMPRESSED_TO + BYTES_COMPRESSED_FROM) / Y where Y = COMPACT_WRITE_BYTES + FLUSH_WRITE_BYTES
Keeping _REJECTED separate from _BYPASSED helps us to understand "wasted" CPU time in compression.
## BlockBasedTableBuilder
Various small refactorings, optimizations, and name clean-ups.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11388
Test Plan:
unit tests added
* `options_settable_test.cc`: use non-deprecated idiom for configuring CompressionOptions from string. The old idiom is tested elsewhere and does not need to be updated to support the new field.
Reviewed By: ajkr
Differential Revision: D45128202
Pulled By: pdillinger
fbshipit-source-id: 5a652bf5c022b7ec340cf79018cccf0686962803
Summary:
This happens when the persisted merge operator not a RocksDB built-in one. This PR improves this error message to include the actual persisted merge operator name. when there is a merge_operator mismatch in `SanityCheckCFOptions()`, for example, going from merge operator "CustomMergeOp" to nullptr, an error message like the following is returned:
"failed the verification on ColumnFamilyOptions::merge_operator--- The specified one is nullptr while the **persisted one is nullptr**."
This happens when the persisted merge operator not a RocksDB built-in one. This PR improves this error message to include the actual persisted merge operator name.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11393
Test Plan: add unit test to check error message when going from merge op -> nullptr and going from merge op1 to merge op 2.
Reviewed By: ajkr
Differential Revision: D45190131
Pulled By: cbi42
fbshipit-source-id: 67712c2fec29c654c15166d1be985e710e6081e5
Summary:
**Context:**
The existing stat rocksdb.sst.read.micros does not reflect each of compaction and flush cases but aggregate them, which is not so helpful for us to understand IO read behavior of each of them.
**Summary**
- Update `StopWatch` and `RandomAccessFileReader` to record `rocksdb.sst.read.micros` and `rocksdb.file.{flush/compaction}.read.micros`
- Fixed the default histogram in `RandomAccessFileReader`
- New field `ReadOptions/IOOptions::io_activity`; Pass `ReadOptions` through paths under db open, flush and compaction to where we can prepare `IOOptions` and pass it to `RandomAccessFileReader`
- Use `thread_status_util` for assertion in `DbStressFSWrapper` for continuous testing on we are passing correct `io_activity` under db open, flush and compaction
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11288
Test Plan:
- **Stress test**
- **Db bench 1: rocksdb.sst.read.micros COUNT ≈ sum of rocksdb.file.read.flush.micros's and rocksdb.file.read.compaction.micros's.** (without blob)
- May not be exactly the same due to `HistogramStat::Add` only guarantees atomic not accuracy across threads.
```
./db_bench -db=/dev/shm/testdb/ -statistics=true -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -target_file_size_base=655 -disable_auto_compactions=false -compression_type=none -bloom_bits=3 (-use_plain_table=1 -prefix_size=10)
```
```
// BlockBasedTable
rocksdb.sst.read.micros P50 : 2.009374 P95 : 4.968548 P99 : 8.110362 P100 : 43.000000 COUNT : 40456 SUM : 114805
rocksdb.file.read.flush.micros P50 : 1.871841 P95 : 3.872407 P99 : 5.540541 P100 : 43.000000 COUNT : 2250 SUM : 6116
rocksdb.file.read.compaction.micros P50 : 2.023109 P95 : 5.029149 P99 : 8.196910 P100 : 26.000000 COUNT : 38206 SUM : 108689
// PlainTable
Does not apply
```
- **Db bench 2: performance**
**Read**
SETUP: db with 900 files
```
./db_bench -db=/dev/shm/testdb/ -benchmarks="fillseq" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -disable_auto_compactions=true -target_file_size_base=655 -compression_type=none
```run till convergence
```
./db_bench -seed=1678564177044286 -use_existing_db=true -db=/dev/shm/testdb -benchmarks=readrandom[-X60] -statistics=true -num=1000000 -disable_auto_compactions=true -compression_type=none -bloom_bits=3
```
Pre-change
`readrandom [AVG 60 runs] : 21568 (± 248) ops/sec`
Post-change (no regression, -0.3%)
`readrandom [AVG 60 runs] : 21486 (± 236) ops/sec`
**Compaction/Flush**run till convergence
```
./db_bench -db=/dev/shm/testdb2/ -seed=1678564177044286 -benchmarks="fillseq[-X60]" -key_size=32 -value_size=512 -num=50000 -write_buffer_size=655 -disable_auto_compactions=false -target_file_size_base=655 -compression_type=none
rocksdb.sst.read.micros COUNT : 33820
rocksdb.sst.read.flush.micros COUNT : 1800
rocksdb.sst.read.compaction.micros COUNT : 32020
```
Pre-change
`fillseq [AVG 46 runs] : 1391 (± 214) ops/sec; 0.7 (± 0.1) MB/sec`
Post-change (no regression, ~-0.4%)
`fillseq [AVG 46 runs] : 1385 (± 216) ops/sec; 0.7 (± 0.1) MB/sec`
Reviewed By: ajkr
Differential Revision: D44007011
Pulled By: hx235
fbshipit-source-id: a54c89e4846dfc9a135389edf3f3eedfea257132
Summary:
The old cleanup code had a race condition:
1. Test thread: DestroyDB() marked a file as trash
2. DeleteScheduler thread: Got the file's size and decided to delete it in chunks
3. Test thread: DestroyDir() deleted that trash file
4. DeleteScheduler thread: Began deleting in chunks starting by calling ReopenWritableFile(). Unfortunately this recreates the deleted trash file
5. Test thread: DestroyDir() fails to remove the parent directory because it contains the file created in 4.
6. Test thread: Checkpoint::Create() fails due to the directory already existing
It could be repro'd with the following patch/command.
Patch:
```
diff --git a/file/delete_scheduler.cc b/file/delete_scheduler.cc
index 8a2d1615d..337d24a60 100644
--- a/file/delete_scheduler.cc
+++ b/file/delete_scheduler.cc
@@ -317,6 +317,12 @@ Status DeleteScheduler::DeleteTrashFile(const std::string& path_in_trash,
&num_hard_links, nullptr);
if (my_status.ok()) {
if (num_hard_links == 1) {
+ // Give some time for DestroyDir() to delete file entries. Then, the
+ // below `ReopenWritableFile()` will recreate files, preventing the
+ // parent directory from being deleted.
+ if (rand() % 2 == 0) {
+ usleep(1000);
+ }
std::unique_ptr<FSWritableFile> wf;
my_status = fs_->ReopenWritableFile(path_in_trash, FileOptions(), &wf,
nullptr);
diff --git a/file/file_util.cc b/file/file_util.cc
index 43608fcdc..2cee1ad8e 100644
--- a/file/file_util.cc
+++ b/file/file_util.cc
@@ -263,6 +263,13 @@ Status DestroyDir(Env* env, const std::string& dir) {
}
}
+ // Give some time for the DeleteScheduler thread's ReopenWritableFile() to
+ // recreate deleted files
+ if (dir.find("checkpoint") != std::string::npos) {
+ fprintf(stderr, "waiting to destroy %s\n", dir.c_str());
+ usleep(10000);
+ }
+
if (s.ok()) {
s = env->DeleteDir(dir);
// DeleteDir might or might not report NotFound
```
Command:
```
TEST_TMPDIR=/dev/shm python3 tools/db_crashtest.py blackbox --simple --write_buffer_size=131072 --target_file_size_base=131072 --max_bytes_for_level_base=524288 --checkpoint_one_in=100 --clear_column_family_one_in=0 --max_key=1000 --value_size_mult=33 --sst_file_manager_bytes_per_truncate=4096 --sst_file_manager_bytes_per_sec=1048576 --interval=3 --compression_type=none --sync_fault_injection=1
```
Obviously we don't want to use scheduled deletion here as we need the checkpoint directory deleted immediately. I suspect the DestroyDir() was an attempt to fixup incomplete DestroyDB()s. Now that we expect DestroyDB() to be complete I removed that code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11389
Reviewed By: hx235
Differential Revision: D45137142
Pulled By: ajkr
fbshipit-source-id: 2af743d342c77cc414fd25fc4c9d7c9c6079ad24
Summary:
during manual compaction (CompactRange()), L0->L1 trivial move is disabled when only L0 overlaps with compacting key range (introduced in https://github.com/facebook/rocksdb/issues/7368 to enforce kForce* contract). This can cause large memory usage due to compaction readahead when number of L0 files is large. This PR allows L0->L1 trivial move in this case, and will do a L1 -> L1 intra-level compaction when needed (`bottommost_level_compaction` is kForce*). In brief, consider a DB with only L0 file, and user calls CompactRange(kForce, nullptr, nullptr),
- before this PR, RocksDB does a L0 -> L1 compaction (disallow trivial move),
- after this PR, RocksDB does a L0 -> L1 compaction (allow trivial move), and a L1 -> L1 compaction.
Users can use kForceOptimized to avoid this extra L1->L1 compaction overhead when L0s are overlapping and cannot be trivial moved.
This PR also fixed a bug (see previous discussion in https://github.com/facebook/rocksdb/issues/11041) where `final_output_level` of a manual compaction can be miscalculated when `level_compaction_dynamic_level_bytes=true`. This bug could cause incorrect level being moved when CompactRangeOptions::change_level is specified.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11375
Test Plan: - Added new unit tests to test that L0 -> L1 compaction allows trivial move and L1 -> L1 compaction is done when needed.
Reviewed By: ajkr
Differential Revision: D44943518
Pulled By: cbi42
fbshipit-source-id: e9fb770d17b163c18a623e1d1bd6b81159192708
Summary:
Because of this failure with snappy 1.1.8, ROCKSDB_NO_FBCODE=1
```
Value 3531 is not in range [2000, 3525]
table/table_test.cc:4231: Failure
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11384
Test Plan: run updated test in failing configuration
Reviewed By: ajkr
Differential Revision: D45057161
Pulled By: pdillinger
fbshipit-source-id: 397054f08033315e2e2bd9410f1fa32ddbf3b9c8
Summary:
This test exhibited the following flaky failure:
```
db/db_write_test.cc:653: Failure
db_->Resume()
Corruption: Not active
```
I was able to repro it by applying the following patch to coerce a specific race condition:
```
diff --git a/db/db_write_test.cc b/db/db_write_test.cc
index d82c57376..775ba3cde 100644
--- a/db/db_write_test.cc
+++ b/db/db_write_test.cc
@@ -636,6 +636,10 @@ TEST_P(DBWriteTest, LockWALInEffect) {
ASSERT_TRUE(dbfull()->WALBufferIsEmpty());
ASSERT_OK(db_->UnlockWAL());
+ // Test thread: sleep interval: [0, 3)
+ // In this interval, the file system is active
+ sleep(3);
+
// Fail the WAL flush if applicable
fault_fs->SetFilesystemActive(false);
Status s = Put("key2", "value");
@@ -649,6 +653,11 @@ TEST_P(DBWriteTest, LockWALInEffect) {
ASSERT_OK(db_->LockWAL());
ASSERT_OK(db_->UnlockWAL());
}
+
+ // Test thread: sleep interval: [3, 6)
+ // In this interval, the file system is inactive
+ sleep(3);
+
fault_fs->SetFilesystemActive(true);
ASSERT_OK(db_->Resume());
// Writes should work again
diff --git a/db/flush_job.cc b/db/flush_job.cc
index 8193f594f..602ee2c9f 100644
--- a/db/flush_job.cc
+++ b/db/flush_job.cc
@@ -979,6 +979,10 @@ Status FlushJob::WriteLevel0Table() {
DirFsyncOptions(DirFsyncOptions::FsyncReason::kNewFileSynced));
}
TEST_SYNC_POINT_CALLBACK("FlushJob::WriteLevel0Table", &mems_);
+ // Flush thread: sleep interval: [0, 4)
+ // Upon awakening, the file system will be inactive. Then the MANIFEST
+ // update will fail.
+ sleep(4);
db_mutex_->Lock();
}
base_->Unref();
```
The fix for this scenario is explained in the code change.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11382
Reviewed By: cbi42
Differential Revision: D45027632
Pulled By: ajkr
fbshipit-source-id: 6bfa35a5781c0c080fb74e13f2b2c9f871f7effb
Summary:
In CircleCI build-linux-arm-test-full job (https://app.circleci.com/pipelines/github/facebook/rocksdb/26462/workflows/a9d39d2c-c970-4b0f-9c10-7743beb9771b/jobs/591722), this test exhibited the following flaky failure:
```
db/db_bloom_filter_test.cc:2506: Failure
Expected: (TestGetTickerCount(options, BLOOM_FILTER_USEFUL)) > (65000 * 2), actual: 120558 vs 130000
```
I ssh'd to an instance and observed it cuts memtables at slightly different points across runs. Logging in `ConcurrentArena` pointed to `try_lock()` returning false at different points across runs.
This PR changes the approach to allow a fixed number of keys per memtable flush. I verified the bloom filter useful count is deterministic now even on the CircleCI ARM instance.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11383
Reviewed By: cbi42
Differential Revision: D45036829
Pulled By: ajkr
fbshipit-source-id: b602dacb63955f1af09bf0ed409cde0552805a08
Summary:
When calculating the largest_key in ImportColumnFamilyJob::GetIngestedFileInfo, only the first element of range_del_iter is calculated. If range_del_iter has multiple elements, the largest_key will be wrong
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11381
Reviewed By: cbi42
Differential Revision: D44981450
Pulled By: ajkr
fbshipit-source-id: 584bc7da86295568a96984d2951644f289e578c7
Summary:
Before this PR, in `LevelCompactionBuilder::TryExtendNonL0TrivialMove(index)`, we start from a file at index and expand the compaction input towards right to find files to trivial move. This PR adds the logic to also expand towards left.
Another major change made in this PR is to not expand L0 files through `TryExtendNonL0TrivialMove()`. This happens currently when compacting L0 files to an empty output level. The condition for expanding files in `TryExtendNonL0TrivialMove()` is to check atomic boundary, which does not take into account that L0 files can overlap in key range and are not sorted in key order. So it may include more L0 files than needed and disallow a trivial move. This change is included in this PR so that we don't make it worse by always expanding L0 in both direction.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11347
Test Plan:
* new unit test
* Benchmark does not show obvious improvement or regression:
```
Write sequentially
./db_bench --benchmarks=fillseq --compression_type=lz4 --write_buffer_size=1000000 --num=100000000 --value_size=100 -level_compaction_dynamic_level_bytes --target_file_size_base=7340032 --max_bytes_for_level_base=16777216
Main:
fillseq : 4.726 micros/op 211592 ops/sec 472.607 seconds 100000000 operations; 23.4 MB/s
This PR:
fillseq : 4.755 micros/op 210289 ops/sec 475.534 seconds 100000000 operations; 23.3 MB/s
Write randomly
./db_bench --benchmarks=fillrandom --compression_type=lz4 --write_buffer_size=1000000 --num=100000000 --value_size=100 -level_compaction_dynamic_level_bytes --target_file_size_base=7340032 --max_bytes_for_level_base=16777216
Main:
fillrandom : 16.351 micros/op 61159 ops/sec 1635.066 seconds 100000000 operations; 6.8 MB/s
This PR:
fillrandom : 15.798 micros/op 63298 ops/sec 1579.817 seconds 100000000 operations; 7.0 MB/s
```
Reviewed By: ajkr
Differential Revision: D44645650
Pulled By: cbi42
fbshipit-source-id: 8631f3a6b3f01decbbf18c34f2b62833cb4f9733
Summary:
**Context/Summary:**
ASSERT_EQ will only verify the code of Status, but will not check the state message of Status.
- Assert by checking Status state in `ImportColumnFamilyTest`
- Forgot to set db_comparator_name when creating ExportImportFilesMetaData in `ImportColumnFamilyNegativeTest`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11372
Reviewed By: ajkr
Differential Revision: D45004343
Pulled By: cbi42
fbshipit-source-id: a13d45521df17ead3d6d4c1c1fe1e4c95397ce8b
Summary:
util/ribbon_test.cc: avoid ambiguous reversed operator error in c++20 (and enable checking for the error)
Code would produce errors like this, when compiled with -Wambiguous-reversed-operator under c++20.
```
util/ribbon_test.cc:695:20: error: ISO C++20 considers use of overloaded operator '!=' (with operand types 'KeyGen' (aka '(anonymous namespace)::StandardKeyGen') and 'KeyGen') to be ambiguou
s despite there being a unique best viable function with non-reversed arguments [-Werror,-Wambiguous-reversed-operator]
while (cur != batch_end) {
~~~ ^ ~~~~~~~~~
util/ribbon_test.cc:111:8: note: candidate function with non-reversed arguments
bool operator!=(const StandardKeyGen& other) {
^
util/ribbon_test.cc:107:8: note: ambiguous candidate function with reversed arguments
bool operator==(const StandardKeyGen& other) {
^
```
This will become a hard error in future standards.
Confirmed that no errors were generated when building using clang and c++20:
```
USE_CLANG=1 USE_COROUTINES=1 make
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11371
Reviewed By: meyering
Differential Revision: D44921027
Pulled By: cbi42
fbshipit-source-id: ef25b78260920a4d75a718310688d3a2487ffa87
Summary:
This option is immutable through the life time of the DB open. For now, updating its value between different DB open sessions is also a non compatible change. When I work on support for updating comparator, the type of updates accepted for this option will be supported then.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11362
Test Plan: `make check`
Reviewed By: ltamasi
Differential Revision: D44873870
Pulled By: jowlyzhang
fbshipit-source-id: aa02094754b58d99abf9af4c9a8108c1350254cb
Summary:
Makes it easier to use generated Rust bindings. Constness of these is already part of the C++ API.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/11243
Reviewed By: hx235
Differential Revision: D44840394
Pulled By: ajkr
fbshipit-source-id: bcd1aeb8c959c304148d25b00043bb8c4cd3e0a4
Hui Xiao