Summary:
It'd be nice to use the error status type to distinguish
between user error and system error. For example, GetChildren can fail
listing a backup directory's contents either because a bad path was provided
(user error) or because an operation failed, e.g., a remote storage service
call failed (system error). In the former case, we want to continue and treat
the backup directory as empty; in the latter case, we want to immediately
propagate the error to the caller.
This diff uses NotFound to indicate user error and IOError to indicate
system error. Previously IOError indicated both.
Closes https://github.com/facebook/rocksdb/pull/1644
Differential Revision: D4312157
Pulled By: ajkr
fbshipit-source-id: 51b4f24
Summary:
This diff split ThreadPool to
-ThreadPool (abstract interface exposed in include/rocksdb/threadpool.h)
-ThreadPoolImpl (actual implementation in util/threadpool_imp.h)
This allow us to expose ThreadPool to the user so we can use it as an option later
Test Plan: existing unit tests
Reviewers: andrewkr, yiwu, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D62085
Summary: When rate_bytes_per_sec * refill_period_us_ overflows, the actual limited rate is very low. Handle this case so the rate will be large.
Test Plan: Add a unit test for it.
Reviewers: IslamAbdelRahman, andrewkr
Reviewed By: andrewkr
Subscribers: yiwu, lightmark, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D58929
For ease of reuse and customization as a library
without wrapping.
WinEnvThreads is a class for replacement.
WintEnvIO is a class for reuse and behavior override.
Added private virtual functions for custom override
of fallocate pread for io classes.
Conditionally retrofit thread_posix for use with std::thread
and reuse the same logic. Posix users continue using Posix interfaces.
Enable XPRESS compression in test runs.
Fix master introduced signed/unsigned mismatch.
Comparable with Snappy on comp ratio.
Implemented using Windows API, does not require external package.
Avaiable since Windows 8 and server 2012.
Use -DXPRESS=1 with CMake to enable.
Summary: I broke it in D53781.
Test Plan: tried the same code in util/env_posix.cc and it compiled successfully
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D54303
Summary:
Added this new function, which returns filename, size, and modified
timestamp for each file in the provided directory. The default implementation
retrieves the metadata sequentially using existing functions. In the next diff
I'll make HdfsEnv override this function to use libhdfs's bulk get function.
This won't work on windows due to the path separator.
Test Plan:
new unit test
$ ./env_test --gtest_filter=EnvPosixTest.ConsistentChildrenMetadata
Reviewers: yhchiang, sdong
Reviewed By: sdong
Subscribers: IslamAbdelRahman, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53781
This change impacts only non-buffered I/O on Windows.
Currently, there is a buffer per RandomAccessFile
instance that is protected by a lock. The reason we
maintain the buffer is non-buffered I/O requires an aligned
buffer to work.
XPerf traces demonstrate that we accumulate a considerable
wait time while waiting for that lock.
This change enables to set random access buffer size to zero
which would indicate a per request allocation.
We are expecting that allocation expense would be much less than
I/O costs plus wait time due to the fact that the memory heap
would tend to re-use page aligned allocations especially with the
use of Jemalloc.
This change does not affect buffer use as a read_ahead_buffer for
compaction purposes.
Summary:
This diff adds support for concurrent adds to the skiplist memtable
implementations. Memory allocation is made thread-safe by the addition of
a spinlock, with small per-core buffers to avoid contention. Concurrent
memtable writes are made via an additional method and don't impose a
performance overhead on the non-concurrent case, so parallelism can be
selected on a per-batch basis.
Write thread synchronization is an increasing bottleneck for higher levels
of concurrency, so this diff adds --enable_write_thread_adaptive_yield
(default off). This feature causes threads joining a write batch
group to spin for a short time (default 100 usec) using sched_yield,
rather than going to sleep on a mutex. If the timing of the yield calls
indicates that another thread has actually run during the yield then
spinning is avoided. This option improves performance for concurrent
situations even without parallel adds, although it has the potential to
increase CPU usage (and the heuristic adaptation is not yet mature).
Parallel writes are not currently compatible with
inplace updates, update callbacks, or delete filtering.
Enable it with --allow_concurrent_memtable_write (and
--enable_write_thread_adaptive_yield). Parallel memtable writes
are performance neutral when there is no actual parallelism, and in
my experiments (SSD server-class Linux and varying contention and key
sizes for fillrandom) they are always a performance win when there is
more than one thread.
Statistics are updated earlier in the write path, dropping the number
of DB mutex acquisitions from 2 to 1 for almost all cases.
This diff was motivated and inspired by Yahoo's cLSM work. It is more
conservative than cLSM: RocksDB's write batch group leader role is
preserved (along with all of the existing flush and write throttling
logic) and concurrent writers are blocked until all memtable insertions
have completed and the sequence number has been advanced, to preserve
linearizability.
My test config is "db_bench -benchmarks=fillrandom -threads=$T
-batch_size=1 -memtablerep=skip_list -value_size=100 --num=1000000/$T
-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" on a two-socket
Xeon E5-2660 @ 2.2Ghz with lots of memory and an SSD hard drive. With 1
thread I get ~440Kops/sec. Peak performance for 1 socket (numactl
-N1) is slightly more than 1Mops/sec, at 16 threads. Peak performance
across both sockets happens at 30 threads, and is ~900Kops/sec, although
with fewer threads there is less performance loss when the system has
background work.
Test Plan:
1. concurrent stress tests for InlineSkipList and DynamicBloom
2. make clean; make check
3. make clean; DISABLE_JEMALLOC=1 make valgrind_check; valgrind db_bench
4. make clean; COMPILE_WITH_TSAN=1 make all check; db_bench
5. make clean; COMPILE_WITH_ASAN=1 make all check; db_bench
6. make clean; OPT=-DROCKSDB_LITE make check
7. verify no perf regressions when disabled
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, IslamAbdelRahman, anthony, yhchiang, rven, sdong, guyg8, kradhakrishnan, dhruba
Differential Revision: https://reviews.facebook.net/D50589
Summary:
This diff provides a framework for doing manual
compactions in parallel with other compactions. We now have a deque of manual compactions. We also pass manual compactions as an argument from RunManualCompactions down to
BackgroundCompactions, so that RunManualCompactions can be reentrant.
Parallelism is controlled by the two routines
ConflictingManualCompaction to allow/disallow new parallel/manual
compactions based on already existing ManualCompactions. In this diff, by default manual compactions still have to run exclusive of other compactions. However, by setting the compaction option, exclusive_manual_compaction to false, it is possible to run other compactions in parallel with a manual compaction. However, we are still restricted to one manual compaction per column family at a time. All of these restrictions will be relaxed in future diffs.
I will be adding more tests later.
Test Plan: Rocksdb regression + new tests + valgrind
Reviewers: igor, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, sdong
Reviewed By: sdong
Subscribers: yoshinorim, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47973
* conversion from 'size_t' to 'type', by add static_cast
Tested:
* by build solution on Windows, Linux locally,
* run tests
* build CI system successful
in 64-bit.
Currently, a signed off_t type is being used for the following
interfaces for both offset and the length in bytes:
* `Allocate`
* `RangeSync`
On Linux `off_t` is automatically either 32 or 64-bit depending on
the platform. On Windows it is always a 32-bit signed long which
limits file access and in particular space pre-allocation
to effectively 2 Gb.
Proposal is to replace off_t with uint64_t as a portable type
always access files with 64-bit interfaces.
May need to modify posix code but lack resources to test it.
Summary: Run "make format" for some recent commits.
Test Plan: Build and run tests
Reviewers: IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D49707
introduce a new DBOption random_access_max_buffer_size to limit
the size of the random access buffer used for unbuffered access.
Implement read ahead buffering when enabled.
To that effect propagate compaction_readahead_size and the new option
to the env options to make it available for the implementation.
Add Hint() override so SetupForCompaction() call would call Hint()
readahead can now be setup from both Hint() and EnableReadAhead()
Add new option random_access_max_buffer_size support
db_bench, options_helper to make it string parsable
and the unit test.
Summary:
Give a name for every kill point, and allow users to disable some kill points based on prefixes. The kill points can be passed by db_stress through a command line paramter. This provides a way for users to boost the chance of triggering low frequency kill points
This allow follow up changes in crash test scripts to improve crash test coverage.
Test Plan:
Manually run db_stress with variable values of --kill_random_test and --kill_prefix_blacklist. Like this:
--kill_random_test=2 --kill_prefix_blacklist=Posix,WritableFileWriter::Append,WritableFileWriter::WriteBuffered,WritableFileWriter::Sync
Reviewers: igor, kradhakrishnan, rven, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48735
Summary:
This mirrors https://reviews.facebook.net/D45645
Currently, mmap returns IOError when user tries to read
data past the end of the file. This diff changes the behavior.
Now, we return just the bytes that we can, and report the size
we returned via a Slice result. This is consistent with non-mmap
behavior and also pread() system call.
Summary. A change https://reviews.facebook.net/differential/diff/224721/
Has attempted to move common functionality out of platform dependent
code to a new facility called file_reader_writer.
This includes:
- perf counters
- Buffering
- RateLimiting
However, the change did not attempt to refactor Windows code.
To mitigate, we introduce new quering interfaces such as UseOSBuffer(),
GetRequiredBufferAlignment() and ReaderWriterForward()
for pure forwarding where required.
Introduce WritableFile got a new method Truncate(). This is to communicate
to the file as to how much data it has on close.
- When space is pre-allocated on Linux it is filled with zeros implicitly,
no such thing exist on Windows so we must truncate file on close.
- When operating in unbuffered mode the last page is filled with zeros but we still want to truncate.
Previously, Close() would take care of it but now buffer management is shifted to the wrappers and the file has
no idea about the file true size.
This means that Close() on the wrapper level must always include
Truncate() as well as wrapper __dtor should call Close() and
against double Close().
Move buffered/unbuffered write logic to the wrapper.
Utilize Aligned buffer class.
Adjust tests and implement Truncate() where necessary.
Come up with reasonable defaults for new virtual interfaces.
Forward calls for RandomAccessReadAhead class to avoid double
buffering and locking (double locking in unbuffered mode on WIndows).
