Summary:
folly DistributedMutex is faster than standard mutexes though
imposes some static obligations on usage. See
https://github.com/facebook/folly/blob/main/folly/synchronization/DistributedMutex.h
for details. Here we use this alternative for our Cache implementations
(especially LRUCache) for better locking performance, when RocksDB is
compiled with folly.
Also added information about which distributed mutex implementation is
being used to cache_bench output and to DB LOG.
Intended follow-up:
* Use DMutex in more places, perhaps improving API to support non-scoped
locking
* Fix linking with fbcode compiler (needs ROCKSDB_NO_FBCODE=1 currently)
Credit: Thanks Siying for reminding me about this line of work that was previously
left unfinished.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10179
Test Plan:
for correctness, existing tests. CircleCI config updated.
Also Meta-internal buck build updated.
For performance, ran simultaneous before & after cache_bench. Out of three
comparison runs, the middle improvement to ops/sec was +21%:
Baseline: USE_CLANG=1 DEBUG_LEVEL=0 make -j24 cache_bench (fbcode
compiler)
```
Complete in 20.201 s; Rough parallel ops/sec = 1584062
Thread ops/sec = 107176
Operation latency (ns):
Count: 32000000 Average: 9257.9421 StdDev: 122412.04
Min: 134 Median: 3623.0493 Max: 56918500
Percentiles: P50: 3623.05 P75: 10288.02 P99: 30219.35 P99.9: 683522.04 P99.99: 7302791.63
```
New: (add USE_FOLLY=1)
```
Complete in 16.674 s; Rough parallel ops/sec = 1919135 (+21%)
Thread ops/sec = 135487
Operation latency (ns):
Count: 32000000 Average: 7304.9294 StdDev: 108530.28
Min: 132 Median: 3777.6012 Max: 91030902
Percentiles: P50: 3777.60 P75: 10169.89 P99: 24504.51 P99.9: 59721.59 P99.99: 1861151.83
```
Reviewed By: anand1976
Differential Revision: D37182983
Pulled By: pdillinger
fbshipit-source-id: a17eb05f25b832b6a2c1356f5c657e831a5af8d1
Summary:
While the yield instruction conseptually sounds correct on most platforms it is
a simple nop that doesn't delay the execution anywhere close to what an x86
pause instruction does. In other projects with spin-wait loops an isb has been
observed to be much closer to the x86 behavior.
On a Graviton3 system the following test improves on average by 2x with this
change averaged over 20 runs:
```
./db_bench -benchmarks=fillrandom -threads=64 -batch_size=1
-memtablerep=skip_list -value_size=100 --num=100000
level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999
-disable_auto_compactions --max_write_buffer_number=8 -max_background_flushes=8
--disable_wal --write_buffer_size=160000000 --block_size=16384
--allow_concurrent_memtable_write -compression_type none
```
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10118
Reviewed By: jay-zhuang
Differential Revision: D37120578
fbshipit-source-id: c20bde4298222edfab7ff7cb6d42497e7012400d
Summary:
__builtin_prefetch(...., 1) prefetches into the L2 cache on x86 while the same
emits a pldl3keep instruction on arm64 which doesn't seem to be close enough.
Testing on a Graviton3, and M1 system with memtablerep_bench fillrandom and
skiplist througpuh increased as follows adjusting the 1 to 2 or 3:
```
1 -> 2 1 -> 3
----------------------------
Graviton3 +10% +15%
M1 +10% +10%
```
Given that prefetching into the L1 cache seems to help, I chose that conversion
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10117
Reviewed By: pdillinger
Differential Revision: D37120475
fbshipit-source-id: db1ef43f941445019c68316500a2250acc643d5e
Summary:
Currently, the DB directory file descriptor is left open until the deconstruction process (`DB::Close()` does not close the file descriptor). To verify this, comment out the lines between `db_ = nullptr` and `db_->Close()` (line 512, 513, 514, 515 in ldb_cmd.cc) to leak the ``db_'' object, build `ldb` tool and run
```
strace --trace=open,openat,close ./ldb --db=$TEST_TMPDIR --ignore_unknown_options put K1 V1 --create_if_missing
```
There is one directory file descriptor that is not closed in the strace log.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10049
Test Plan: Add a new unit test DBBasicTest.DBCloseAllDirectoryFDs: Open a database with different WAL directory and three different data directories, and all directory file descriptors should be closed after calling Close(). Explicitly call Close() after a directory file descriptor is not used so that the counter of directory open and close should be equivalent.
Reviewed By: ajkr, hx235
Differential Revision: D36722135
Pulled By: littlepig2013
fbshipit-source-id: 07bdc2abc417c6b30997b9bbef1f79aa757b21ff
Summary:
There are currently some preprocessor checks that assume support for Visual Studio versions older than 2015 (i.e., 0 < _MSC_VER < 1900), although we don't support them any more.
We removed all code that only compiles on those older versions, except third-party/ files.
The ROCKSDB_NOEXCEPT symbol is now obsolete, since it now always gets replaced by noexcept. We removed it.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10065
Reviewed By: pdillinger
Differential Revision: D36721901
Pulled By: guidotag
fbshipit-source-id: a2892d365ef53cce44a0a7d90dd6b72ee9b5e5f2
Summary:
There are some time-related POSIX APIs that are not available on Windows
(e.g. `localtime_r`), which we have worked around by providing our own
implementations in `port/sys_time.h`. This workaround actually relies on
some ambiguity: on Windows, a call to `localtime_r` calls
`ROCKSDB_NAMESPACE::port::localtime_r` (which is pulled into
`ROCKSDB_NAMESPACE` by a using-declaration), while on other platforms
it calls the global `localtime_r`. This works fine as long as there is only one
candidate function; however, it breaks down when there is more than one
`localtime_r` visible in a scope.
The patch fixes this by introducing `ROCKSDB_NAMESPACE::port::{TimeVal, GetTimeOfDay, LocalTimeR}`
to eliminate any ambiguity.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10045
Test Plan: `make check`
Reviewed By: riversand963
Differential Revision: D36639372
Pulled By: ltamasi
fbshipit-source-id: fc13dbfa421b7c8918111a6d9e24ce77e91a7c50
Summary:
ROCKSDB_SUPPORT_THREAD_LOCAL definition has been removed.
`__thread`(#define) has been replaced with `thread_local`(C++ keyword) across the code base.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10015
Reviewed By: siying
Differential Revision: D36485491
Pulled By: pdillinger
fbshipit-source-id: 6522d212514ee190b90b4e2750c80c7e34013c78
Summary:
Changed the static objects that had non-trivial destructors to use the STATIC_AVOID_DESTRUCTION construct.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9958
Reviewed By: pdillinger
Differential Revision: D36442982
Pulled By: mrambacher
fbshipit-source-id: 029d47b1374d30d198bfede369a4c0ae7a4eb519
Summary:
These methods allow for more thorough testing of the ObjectRegistry and Customizable infrastructure in a simpler manner. With this change, the Customizable tests can now check what factories are registered and attempt to create each of them in a systematic fashion.
With this change, I think all of the factories registered with the ObjectRegistry/CreateFromString are now tested via the customizable_test classes.
Note that there were a few other minor changes. There was a "posix://*" register with the ObjectRegistry which was missed during the PatternEntry conversion -- these changes found that. The nickname and default names for the FileSystem classes was also inverted.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9358
Reviewed By: pdillinger
Differential Revision: D33433542
Pulled By: mrambacher
fbshipit-source-id: 9a32da74e6620745b4eeffb2712be70eeeadfa7e
Summary:
Right now we still don't fully use std::numeric_limits but use a macro, mainly for supporting VS 2013. Right now we only support VS 2017 and up so it is not a problem. The code comment claims that MinGW still needs it. We don't have a CI running MinGW so it's hard to validate. since we now require C++17, it's hard to imagine MinGW would still build RocksDB but doesn't support std::numeric_limits<>.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9954
Test Plan: See CI Runs.
Reviewed By: riversand963
Differential Revision: D36173954
fbshipit-source-id: a35a73af17cdcae20e258cdef57fcf29a50b49e0
Summary:
Especially after updating to C++17, I don't see a compelling case for
*requiring* any folly components in RocksDB. I was able to purge the existing
hard dependencies, and it can be quite difficult to strip out non-trivial components
from folly for use in RocksDB. (The prospect of doing that on F14 has changed
my mind on the best approach here.)
But this change creates an optional integration where we can plug in
components from folly at compile time, starting here with F14FastMap to replace
std::unordered_map when possible (probably no public APIs for example). I have
replaced the biggest CPU users of std::unordered_map with compile-time
pluggable UnorderedMap which will use F14FastMap when USE_FOLLY is set.
USE_FOLLY is always set in the Meta-internal buck build, and a simulation of
that is in the Makefile for public CI testing. A full folly build is not needed, but
checking out the full folly repo is much simpler for getting the dependency,
and anything else we might want to optionally integrate in the future.
Some picky details:
* I don't think the distributed mutex stuff is actually used, so it was easy to remove.
* I implemented an alternative to `folly::constexpr_log2` (which is much easier
in C++17 than C++11) so that I could pull out the hard dependencies on
`ConstexprMath.h`
* I had to add noexcept move constructors/operators to some types to make
F14's complainUnlessNothrowMoveAndDestroy check happy, and I added a
macro to make that easier in some common cases.
* Updated Meta-internal buck build to use folly F14Map (always)
No updates to HISTORY.md nor INSTALL.md as this is not (yet?) considered a
production integration for open source users.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9546
Test Plan:
CircleCI tests updated so that a couple of them use folly.
Most internal unit & stress/crash tests updated to use Meta-internal latest folly.
(Note: they should probably use buck but they currently use Makefile.)
Example performance improvement: when filter partitions are pinned in cache,
they are tracked by PartitionedFilterBlockReader::filter_map_ and we can build
a test that exercises that heavily. Build DB with
```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench -benchmarks=fillrandom -num=10000000 -disable_wal=1 -write_buffer_size=30000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters
```
and test with (simultaneous runs with & without folly, ~20 times each to see
convergence)
```
TEST_TMPDIR=/dev/shm/rocksdb ./db_bench_folly -readonly -use_existing_db -benchmarks=readrandom -num=10000000 -bloom_bits=16 -compaction_style=2 -fifo_compaction_max_table_files_size_mb=10000 -fifo_compaction_allow_compaction=0 -partition_index_and_filters -duration=40 -pin_l0_filter_and_index_blocks_in_cache
```
Average ops/s no folly: 26229.2
Average ops/s with folly: 26853.3 (+2.4%)
Reviewed By: ajkr
Differential Revision: D34181736
Pulled By: pdillinger
fbshipit-source-id: ffa6ad5104c2880321d8a1aa7187e00ab0d02e94
Summary:
Drop support for some old compilers by requiring C++17 standard
(or higher). See https://github.com/facebook/rocksdb/issues/9388
First modification based on this is to remove some conditional compilation in slice.h (also
better for ODR)
Also in this PR:
* Fix some Makefile formatting that seems to affect ASSERT_STATUS_CHECKED config in
some cases
* Add c_test to NON_PARALLEL_TEST in Makefile
* Fix a clang-analyze reported "potential leak" in lru_cache_test
* Better "compatibility" definition of DEFINE_uint32 for old versions of gflags
* Fix a linking problem with shared libraries in Makefile (`./random_test: error while loading shared libraries: librocksdb.so.6.29: cannot open shared object file: No such file or directory`)
* Always set ROCKSDB_SUPPORT_THREAD_LOCAL and use thread_local (from C++11)
* TODO in later PR: clean up that obsolete flag
* Fix a cosmetic typo in c.h (https://github.com/facebook/rocksdb/issues/9488)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9481
Test Plan:
CircleCI config substantially updated.
* Upgrade to latest Ubuntu images for each release
* Generally prefer Ubuntu 20, but keep a couple Ubuntu 16 builds with oldest supported
compilers, to ensure compatibility
* Remove .circleci/cat_ignore_eagain except for Ubuntu 16 builds, because this is to work
around a kernel bug that should not affect anything but Ubuntu 16.
* Remove designated gcc-9 build, because the default linux build now uses GCC 9 from
Ubuntu 20.
* Add some `apt-key add` to fix some apt "couldn't be verified" errors
* Generally drop SKIP_LINK=1; work-around no longer needed
* Generally `add-apt-repository` before `apt-get update` as manual testing indicated the
reverse might not work.
Travis:
* Use gcc-7 by default (remove specific gcc-7 and gcc-4.8 builds)
* TODO in later PR: fix s390x "Assembler messages: Error: invalid switch -march=z14" failure
AppVeyor:
* Completely dropped because we are dropping VS2015 support and CircleCI covers
VS >= 2017
Also local testing with old gflags (out of necessity when using ROCKSDB_NO_FBCODE=1).
Reviewed By: mrambacher
Differential Revision: D33946377
Pulled By: pdillinger
fbshipit-source-id: ae077c823905b45370a26c0103ada119459da6c1
Summary:
Loose ends relate to mmap on 32-bit systems. (Testing is more
complicated when the feature was completely disabled on 32-bit.)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9386
Test Plan: CI
Reviewed By: ajkr
Differential Revision: D33590715
Pulled By: pdillinger
fbshipit-source-id: f2637036a538a552200adee65b6765fce8cae27b
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:
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 Docker build environment for RocksJava on s390x
* Cache alignment size for s390x was incorrectly calculated on gcc 6.4.0
* Tighter control over which installed version of Java is used is required - build now correctly adheres to `JAVA_HOME` if it is set
* Alpine build scripts should be used on Alpine (previously CentOS script worked by falling through to minimal gcc version)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9321
Reviewed By: mrambacher
Differential Revision: D33259624
Pulled By: jay-zhuang
fbshipit-source-id: d791a5150581344925c3c3f9cbb9a3622d63b3b6
Summary:
Added missing include, and cleaned up to make same mistake less
likely in future (minimize conditional compilation)
Fixes https://github.com/facebook/rocksdb/issues/9183
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9209
Test Plan: added to existing test
Reviewed By: mrambacher
Differential Revision: D32631390
Pulled By: pdillinger
fbshipit-source-id: 63a0501855cf5fac9e22ca1e5c4f53725dbf3f93
Summary:
The comments in the `#endif` section at the end of the file were in the
wrong order.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9033
Reviewed By: mrambacher
Differential Revision: D31935856
Pulled By: ajkr
fbshipit-source-id: 24aca039993d6e27022cfe8d6434e90f2934c87c
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:
The cyclic dependency was:
- `StressTest::OperateDb()` locks the mutex for key 'k'
- `StressTest::OperateDb()` calls a function like `PauseBackgroundWork()`, which waits for pending compaction to complete.
- The pending compaction reaches key `k` and `DbStressCompactionFilter::FilterV2()` calls `Lock()` on that key's mutex, which hangs forever.
The cycle can be broken by using a new function, `port::Mutex::TryLock()`, which returns immediately upon failure to acquire a lock. In that case `DbStressCompactionFilter::FilterV2()` can just decide to keep the key.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8956
Reviewed By: riversand963
Differential Revision: D31183718
Pulled By: ajkr
fbshipit-source-id: 329e4a31ce43085af174cf367ef560b5a04399c5
Summary:
Made SystemClock into a Customizable class, complete with CreateFromString.
Cleaned up some of the existing SystemClock implementations that were redundant (NoSleep was the same as the internal one for MockEnv).
Changed MockEnv construction to allow Clock to be passed to the Memory/MockFileSystem.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8636
Reviewed By: zhichao-cao
Differential Revision: D30483360
Pulled By: mrambacher
fbshipit-source-id: cd0e3a876c39f8c98fe13374c06e8edbd5b9f2a1
Summary:
Old typedef syntax is confusing
Most but not all changes with
perl -pi -e 's/typedef (.*) ([a-zA-Z0-9_]+);/using $2 = $1;/g' list_of_files
make format
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8751
Test Plan: existing
Reviewed By: zhichao-cao
Differential Revision: D30745277
Pulled By: pdillinger
fbshipit-source-id: 6f65f0631c3563382d43347896020413cc2366d9
Summary:
Env::GenerateUniqueId() works fine on Windows and on POSIX
where /proc/sys/kernel/random/uuid exists. Our other implementation is
flawed and easily produces collision in a new multi-threaded test.
As we rely more heavily on DB session ID uniqueness, this becomes a
serious issue.
This change combines several individually suitable entropy sources
for reliable generation of random unique IDs, with goal of uniqueness
and portability, not cryptographic strength nor maximum speed.
Specifically:
* Moves code for getting UUIDs from the OS to port::GenerateRfcUuid
rather than in Env implementation details. Callers are now told whether
the operation fails or succeeds.
* Adds an internal API GenerateRawUniqueId for generating high-quality
128-bit unique identifiers, by combining entropy from three "tracks":
* Lots of info from default Env like time, process id, and hostname.
* std::random_device
* port::GenerateRfcUuid (when working)
* Built-in implementations of Env::GenerateUniqueId() will now always
produce an RFC 4122 UUID string, either from platform-specific API or
by converting the output of GenerateRawUniqueId.
DB session IDs now use GenerateRawUniqueId while DB IDs (not as
critical) try to use port::GenerateRfcUuid but fall back on
GenerateRawUniqueId with conversion to an RFC 4122 UUID.
GenerateRawUniqueId is declared and defined under env/ rather than util/
or even port/ because of the Env dependency.
Likely follow-up: enhance GenerateRawUniqueId to be faster after the
first call and to guarantee uniqueness within the lifetime of a single
process (imparting the same property onto DB session IDs).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8708
Test Plan:
A new mini-stress test in env_test checks the various public
and internal APIs for uniqueness, including each track of
GenerateRawUniqueId individually. We can't hope to verify anywhere close
to 128 bits of entropy, but it can at least detect flaws as bad as the
old code. Serial execution of the new tests takes about 350 ms on
my machine.
Reviewed By: zhichao-cao, mrambacher
Differential Revision: D30563780
Pulled By: pdillinger
fbshipit-source-id: de4c9ff4b2f581cf784fcedb5f39f16e5185c364
Summary:
Useful in some places for object uniqueness across processes.
Currently used for generating a host-wide identifier of Cache objects
but expected to be used soon in some unique id generation code.
`int64_t` is chosen for return type because POSIX uses signed integer type,
usually `int`, for `pid_t` and Windows uses `DWORD`, which is `uint32_t`.
Future work: avoid copy-pasted declarations in port_*.h, perhaps with
port_common.h always included from port.h
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8693
Test Plan: manual for now
Reviewed By: ajkr, anand1976
Differential Revision: D30492876
Pulled By: pdillinger
fbshipit-source-id: 39fc2788623cc9f4787866bdb67a4d183dde7eef
Summary:
In https://github.com/facebook/rocksdb/issues/8539 I accidentally only checked for GCC TSAN, which is
what I tested locally, while CircleCI and FB CI use clang TSAN. Related:
other existing code like in stack_trace.cc only check for clang TSAN.
I've now standardized these to the GCC convention in port/lang.h, so now
#ifdef __SANITIZE_THREAD__
can check for any TSAN (assuming lang.h include)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8543
Test Plan:
Put an assert(false) in slice_test and look for the NOTE
about "signal-unsafe call", both GCC and clang. Eventually, CircleCI
TSAN in https://github.com/facebook/rocksdb/issues/8538
Reviewed By: zhichao-cao
Differential Revision: D29728483
Pulled By: pdillinger
fbshipit-source-id: 8a3b8015c2ed48078214c3ee17146a2c3f11c9f7
Summary:
MyRocks apparently uses valgrind to check for unreachable
unfreed data, which is stricter than our valgrind checks. Internal ref:
D29257815
This patch adds valgrind support to STATIC_AVOID_DESTRUCTION so that it's
not reported with those stricter checks.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8503
Test Plan:
make valgrind_test
Also, with modified VALGRIND_OPTS (see Makefile), more kinds of
failures seen before than after this commit.
Reviewed By: ajkr, yizhang82
Differential Revision: D29597784
Pulled By: pdillinger
fbshipit-source-id: 360de157a176aec4d1be99ca20d160ecd47c0873
Summary:
Original author: kraj (https://github.com/facebook/rocksdb/issues/8413)
We have a hack to ensure clang's `posix_memalign()` hack works to be
compatible with glibc's `posix_memalign()` declaration. Our side of the
hack is irrelevant and should be omitted when not using glibc.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8425
Reviewed By: mrambacher
Differential Revision: D29239029
Pulled By: ajkr
fbshipit-source-id: 12b900f50a4823b880a6558f25d8590dbfc0aa26
Summary:
Allow using WindowsThread with Mingw
Most Mingw builds require Posix threads in order to use std::thread.
As per https://github.com/facebook/rocksdb/issues/7764, this is not always the case.
That being considered, we're going to improve the Mingw thread model
checks.
Closes: https://github.com/facebook/rocksdb/issues/7764
Signed-off-by: Lucian Petrut <lpetrut@cloudbasesolutions.com>
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8108
Reviewed By: jay-zhuang
Differential Revision: D27365778
Pulled By: mrambacher
fbshipit-source-id: 2c15b1f04ae90e1e3a25a33e86ceb779224a9529
Summary:
This change gathers and publishes statistics about the
kinds of items in block cache. This is especially important for
profiling relative usage of cache by index vs. filter vs. data blocks.
It works by iterating over the cache during periodic stats dump
(InternalStats, stats_dump_period_sec) or on demand when
DB::Get(Map)Property(kBlockCacheEntryStats), except that for
efficiency and sharing among column families, saved data from
the last scan is used when the data is not considered too old.
The new information can be seen in info LOG, for example:
Block cache LRUCache@0x7fca62229330 capacity: 95.37 MB collections: 8 last_copies: 0 last_secs: 0.00178 secs_since: 0
Block cache entry stats(count,size,portion): DataBlock(7092,28.24 MB,29.6136%) FilterBlock(215,867.90 KB,0.888728%) FilterMetaBlock(2,5.31 KB,0.00544%) IndexBlock(217,180.11 KB,0.184432%) WriteBuffer(1,256.00 KB,0.262144%) Misc(1,0.00 KB,0%)
And also through DB::GetProperty and GetMapProperty (here using
ldb just for demonstration):
$ ./ldb --db=/dev/shm/dbbench/ get_property rocksdb.block-cache-entry-stats
rocksdb.block-cache-entry-stats.bytes.data-block: 0
rocksdb.block-cache-entry-stats.bytes.deprecated-filter-block: 0
rocksdb.block-cache-entry-stats.bytes.filter-block: 0
rocksdb.block-cache-entry-stats.bytes.filter-meta-block: 0
rocksdb.block-cache-entry-stats.bytes.index-block: 178992
rocksdb.block-cache-entry-stats.bytes.misc: 0
rocksdb.block-cache-entry-stats.bytes.other-block: 0
rocksdb.block-cache-entry-stats.bytes.write-buffer: 0
rocksdb.block-cache-entry-stats.capacity: 8388608
rocksdb.block-cache-entry-stats.count.data-block: 0
rocksdb.block-cache-entry-stats.count.deprecated-filter-block: 0
rocksdb.block-cache-entry-stats.count.filter-block: 0
rocksdb.block-cache-entry-stats.count.filter-meta-block: 0
rocksdb.block-cache-entry-stats.count.index-block: 215
rocksdb.block-cache-entry-stats.count.misc: 1
rocksdb.block-cache-entry-stats.count.other-block: 0
rocksdb.block-cache-entry-stats.count.write-buffer: 0
rocksdb.block-cache-entry-stats.id: LRUCache@0x7f3636661290
rocksdb.block-cache-entry-stats.percent.data-block: 0.000000
rocksdb.block-cache-entry-stats.percent.deprecated-filter-block: 0.000000
rocksdb.block-cache-entry-stats.percent.filter-block: 0.000000
rocksdb.block-cache-entry-stats.percent.filter-meta-block: 0.000000
rocksdb.block-cache-entry-stats.percent.index-block: 2.133751
rocksdb.block-cache-entry-stats.percent.misc: 0.000000
rocksdb.block-cache-entry-stats.percent.other-block: 0.000000
rocksdb.block-cache-entry-stats.percent.write-buffer: 0.000000
rocksdb.block-cache-entry-stats.secs_for_last_collection: 0.000052
rocksdb.block-cache-entry-stats.secs_since_last_collection: 0
Solution detail - We need some way to flag what kind of blocks each
entry belongs to, preferably without changing the Cache API.
One of the complications is that Cache is a general interface that could
have other users that don't adhere to whichever convention we decide
on for keys and values. Or we would pay for an extra field in the Handle
that would only be used for this purpose.
This change uses a back-door approach, the deleter, to indicate the
"role" of a Cache entry (in addition to the value type, implicitly).
This has the added benefit of ensuring proper code origin whenever we
recognize a particular role for a cache entry; if the entry came from
some other part of the code, it will use an unrecognized deleter, which
we simply attribute to the "Misc" role.
An internal API makes for simple instantiation and automatic
registration of Cache deleters for a given value type and "role".
Another internal API, CacheEntryStatsCollector, solves the problem of
caching the results of a scan and sharing them, to ensure scans are
neither excessive nor redundant so as not to harm Cache performance.
Because code is added to BlocklikeTraits, it is pulled out of
block_based_table_reader.cc into its own file.
This is a reformulation of https://github.com/facebook/rocksdb/issues/8276, without the type checking option
(could still be added), and with actual stat gathering.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8297
Test Plan: manual testing with db_bench, and a couple of basic unit tests
Reviewed By: ltamasi
Differential Revision: D28488721
Pulled By: pdillinger
fbshipit-source-id: 472f524a9691b5afb107934be2d41d84f2b129fb
Summary:
Refactor kill point to one single class, rather than several extern variables. The intention was to drop unflushed data before killing to simulate some job, and I tried to a pointer to fault ingestion fs to the killing class, but it ended up with harder than I thought. Perhaps we'll need to do this in another way. But I thought the refactoring itself is good so I send it out.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8241
Test Plan: make release and run crash test for a while.
Reviewed By: anand1976
Differential Revision: D28078486
fbshipit-source-id: f9182c1455f52e6851c13f88a21bade63bcec45f
Summary:
The code for strcmp that was present does work when compiled for Windows unicode file paths.
Needs backporting to:
* 6.17.fb
* 6.18.fb
* 6.19.fb
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8190
Reviewed By: akankshamahajan15
Differential Revision: D27765588
Pulled By: jay-zhuang
fbshipit-source-id: 89f8a5ac61fd7edc758340dfd335b0a5f96dae6e
Summary:
`strerror()` is not thread-safe, using `strerror_r()` instead. The API could be different on the different platforms, used the code from 0deef031cb/folly/String.cpp (L457)
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8087
Reviewed By: mrambacher
Differential Revision: D27267151
Pulled By: jay-zhuang
fbshipit-source-id: 4b8856d1ec069d5f239b764750682c56e5be9ddb
Summary:
For performance purposes, the lower level routines were changed to use a SystemClock* instead of a std::shared_ptr<SystemClock>. The shared ptr has some performance degradation on certain hardware classes.
For most of the system, there is no risk of the pointer being deleted/invalid because the shared_ptr will be stored elsewhere. For example, the ImmutableDBOptions stores the Env which has a std::shared_ptr<SystemClock> in it. The SystemClock* within the ImmutableDBOptions is essentially a "short cut" to gain access to this constant resource.
There were a few classes (PeriodicWorkScheduler?) where the "short cut" property did not hold. In those cases, the shared pointer was preserved.
Using db_bench readrandom perf_level=3 on my EC2 box, this change performed as well or better than 6.17:
6.17: readrandom : 28.046 micros/op 854902 ops/sec; 61.3 MB/s (355999 of 355999 found)
6.18: readrandom : 32.615 micros/op 735306 ops/sec; 52.7 MB/s (290999 of 290999 found)
PR: readrandom : 27.500 micros/op 871909 ops/sec; 62.5 MB/s (367999 of 367999 found)
(Note that the times for 6.18 are prior to revert of the SystemClock).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8033
Reviewed By: pdillinger
Differential Revision: D27014563
Pulled By: mrambacher
fbshipit-source-id: ad0459eba03182e454391b5926bf5cdd45657b67
Summary:
Ignore return value on WinLogger::CloseInternal() when build with -DROCKSDB_ASSERT_STATUS_CHECKED on windows.
It's a good way to ignore check here?
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7955
Reviewed By: jay-zhuang
Differential Revision: D26524145
Pulled By: ajkr
fbshipit-source-id: f2f643e94cde9772617c68b658fb529fffebd8ce
Summary:
Removed the uses of the Legacy FileWrapper classes from the source code. The wrappers were creating an additional layer of indirection/wrapping, as the Env already has a FileSystem.
Moved the Custom FileWrapper classes into the CustomEnv, as these classes are really for the private use the the CustomEnv class.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7851
Reviewed By: anand1976
Differential Revision: D26114816
Pulled By: mrambacher
fbshipit-source-id: db32840e58d969d3a0fa6c25aaf13d6dcdc74150
Summary:
Introduces and uses a SystemClock class to RocksDB. This class contains the time-related functions of an Env and these functions can be redirected from the Env to the SystemClock.
Many of the places that used an Env (Timer, PerfStepTimer, RepeatableThread, RateLimiter, WriteController) for time-related functions have been changed to use SystemClock instead. There are likely more places that can be changed, but this is a start to show what can/should be done. Over time it would be nice to migrate most (if not all) of the uses of the time functions from the Env to the SystemClock.
There are several Env classes that implement these functions. Most of these have not been converted yet to SystemClock implementations; that will come in a subsequent PR. It would be good to unify many of the Mock Timer implementations, so that they behave similarly and be tested similarly (some override Sleep, some use a MockSleep, etc).
Additionally, this change will allow new methods to be introduced to the SystemClock (like https://github.com/facebook/rocksdb/issues/7101 WaitFor) in a consistent manner across a smaller number of classes.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7858
Reviewed By: pdillinger
Differential Revision: D26006406
Pulled By: mrambacher
fbshipit-source-id: ed10a8abbdab7ff2e23d69d85bd25b3e7e899e90
Summary:
The main improvement here is to not include `.` or `..` in the results of `Env::GetChildren`. The occurrence of `.` or `..`; it is non-portable, dependent on the Operating System and the File System. See: https://www.gnu.org/software/libc/manual/html_node/Reading_002fClosing-Directory.html
There were lots of duplicate checks spread through the RocksDB codebase previously to skip `.` and `..`. This new removes the need for those at the source.
Also some minor fixes to `Env::GetChildren`:
* Improve error handling in POSIX implementation
* Remove unnecessary array allocation on Windows
* Fix struct name for Windows Non-UTF-8 API
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7819
Reviewed By: ajkr
Differential Revision: D25837394
Pulled By: jay-zhuang
fbshipit-source-id: 1e137e7218d38b450af9c083f73d5357abcbba2e
Summary:
This PR does the following:
-> Creates a WinFileSystem class. This class is the Windows equivalent of the PosixFileSystem and will be used on Windows systems.
-> Introduces a CustomEnv class. A CustomEnv is an Env that takes a FileSystem as constructor argument. I believe there will only ever be two implementations of this class (PosixEnv and WinEnv). There is still a CustomEnvWrapper class that takes an Env and a FileSystem and wraps the Env calls with the input Env but uses the FileSystem for the FileSystem calls
-> Eliminates the public uses of the LegacyFileSystemWrapper.
With this change in place, there are effectively the following patterns of Env:
- "Base Env classes" (PosixEnv, WinEnv). These classes implement the core Env functions (e.g. Threads) and have a hard-coded input FileSystem. These classes inherit from CompositeEnv, implement the core Env functions (threads) and delegate the FileSystem-like calls to the input file system.
- Wrapped Composite Env classes (MemEnv). These classes take in an Env and a FileSystem. The core env functions are re-directed to the wrapped env. The file system calls are redirected to the input file system
- Legacy Wrapped Env classes. These classes take in an Env input (but no FileSystem). The core env functions are re-directed to the wrapped env. A "Legacy File System" is created using this env and the file system calls directed to the env itself.
With these changes in place, the PosixEnv becomes a singleton -- there is only ever one created. Any other use of the PosixEnv is via another wrapped env. This cleans up some of the issues with the env construction and destruction.
Additionally, there were places in the code that required had an Env when they required a FileSystem. Many of these places would wrap the Env with a LegacyFileSystemWrapper instead of using the env->GetFileSystem(). These places were changed, thereby removing layers of additional redirection (LegacyFileSystem --> Env --> Env::FileSystem).
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7703
Reviewed By: zhichao-cao
Differential Revision: D25762190
Pulled By: anand1976
fbshipit-source-id: 1a088e97fc916f28ac69c149cd1dcad0ab31704b
Summary:
TSAN reports that our stack trace handler makes unsafe calls
during a signal handler. I just tried fixing some of them and I don't
think it's fixable unless we can get away from using FILE stdio. Even if
we can use lower level functions only, I'm not sure it's fixed.
I also tried suppressing the reports with function and file level TSAN
suppression, but that doesn't seem to work, perhaps because the
violation is reported on the callee, not the caller.
So I added a warning to be printed whenever these violations would be
reported that they are practically ignorable.
Internal ref: T77844138
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7723
Test Plan:
run external_sst_file_test with seeded abort(), with TSAN
(TSAN warnings + new warning) and without TSAN (no warning, just stack
trace).
Reviewed By: akankshamahajan15
Differential Revision: D25228011
Pulled By: pdillinger
fbshipit-source-id: 3eda1d6e7ca3cdc64076cf99ae954168837d2818
Summary:
This is a PR generated **semi-automatically** by an internal tool to remove unused includes and `using` statements.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7604
Test Plan: make check
Reviewed By: ajkr
Differential Revision: D24579392
Pulled By: riversand963
fbshipit-source-id: c4bfa6c6b08da1de186690d37eb73d8fff45aecd
Summary:
This PR addresses some build and functional issues on MSVC targets, as a step towards an eventual goal of having RocksDB build successfully for Windows on ARM64.
Addressed issues include:
- BitsSetToOne and CountTrailingZeroBits do not compile on non-x64 MSVC targets. A fallback implementation of BitsSetToOne when Intel intrinsics are not available is added, based on the C++20 `<bit>` popcount implementation in Microsoft's STL.
- The implementation of FloorLog2 for MSVC targets (including x64) gives incorrect results. The unit test easily detects this, but CircleCI is currently configured to only run a specific set of tests for Windows CMake builds, so this seems to have been unnoticed.
- AsmVolatilePause does not use YieldProcessor on Windows ARM64 targets, even though it is available.
- When CondVar::TimedWait calls Microsoft STL's condition_variable::wait_for, it can potentially trigger a bug (just recently fixed in the upcoming VS 16.8's STL) that deadlocks various tests that wait for a timer to execute, since `Timer::Run` doesn't get a chance to execute before being blocked by the test function acquiring the mutex.
- In c_test, `GetTempDir` assumes a POSIX-style temp path.
- `NormalizePath` did not eliminate consecutive POSIX-style path separators on Windows, resulting in test failures in e.g., wal_manager_test.
- Various other test failures.
In a followup PR I hope to modify CircleCI's config.yml to invoke all RocksDB unit tests in Windows CMake builds with CTest, instead of the current use of `run_ci_db_test.ps1` which requires individual tests to be specified and is missing many of the existing tests.
Notes from peterd: FloorLog2 is not yet used in production code (it's for something in progress). I also added a few more inexpensive platform-dependent tests to Windows CircleCI runs. And included facebook/folly#1461 as requested
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7439
Reviewed By: jay-zhuang
Differential Revision: D24021563
Pulled By: pdillinger
fbshipit-source-id: 0ec2027c0d6a494d8a0fe38d9667fc2f7e29f7e7
Peter Dillinger