Summary:
Currently the point lookup values are copied to a string provided by the user.
This incures an extra memcpy cost. This patch allows doing point lookup
via a PinnableSlice which pins the source memory location (instead of
copying their content) and releases them after the content is consumed
by the user. The old API of Get(string) is translated to the new API
underneath.
Here is the summary for improvements:
1. value 100 byte: 1.8% regular, 1.2% merge values
2. value 1k byte: 11.5% regular, 7.5% merge values
3. value 10k byte: 26% regular, 29.9% merge values
The improvement for merge could be more if we extend this approach to
pin the merge output and delay the full merge operation until the user
actually needs it. We have put that for future work.
PS:
Sometimes we observe a small decrease in performance when switching from
t5452014 to this patch but with the old Get(string) API. The difference
is a little and could be noise. More importantly it is safely
cancelled
Closes https://github.com/facebook/rocksdb/pull/1732
Differential Revision: D4374613
Pulled By: maysamyabandeh
fbshipit-source-id: a077f1a
Summary:
File copying happens when creating checkpoints and bulkloading files from different FS partition. We should fsync the files when copying them to guarantee durability. A side effect will be that the dirty pages in file system buffers won't grow too large.
Closes https://github.com/facebook/rocksdb/pull/1728
Differential Revision: D4371083
Pulled By: siying
fbshipit-source-id: 579e14c
Summary:
Improve cache options logging to info log.
Also print the value of
cache_index_and_filter_blocks_with_high_priority.
Closes https://github.com/facebook/rocksdb/pull/1709
Differential Revision: D4358776
Pulled By: yiwu-arbug
fbshipit-source-id: 8f030a0
Summary:
?e_file_max_buffer_size)
If we overwrite WritableFile and has a buffer which has the same
function of buf_. We hope remove the cache function of
WritableFileWriter. So using options.writable_file_max_buffer_size = 0
to disable cache function.
Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
Closes https://github.com/facebook/rocksdb/pull/1628
Differential Revision: D4307219
Pulled By: yiwu-arbug
fbshipit-source-id: 77a6e26
Summary:
Fixes compile error:
In file included from ./util/statistics.h:17:0,
from ./util/stop_watch.h:8,
from ./util/perf_step_timer.h:9,
from ./util/iostats_context_imp.h:8,
from ./util/posix_logger.h:27,
from ./port/util_logger.h:18,
from ./db/auto_roll_logger.h:15,
from db/auto_roll_logger.cc:6:
./util/thread_local.h:65:16: error: 'function' in namespace 'std' does not name a template type
typedef std::function<void(void*, void*)> FoldFunc;
Closes https://github.com/facebook/rocksdb/pull/1656
Differential Revision: D4318702
Pulled By: yiwu-arbug
fbshipit-source-id: 8c5d17a
Summary:
hopefully the last of the gcc-7 compile errors
Closes https://github.com/facebook/rocksdb/pull/1675
Differential Revision: D4332106
Pulled By: IslamAbdelRahman
fbshipit-source-id: 139448c
Summary:
fixes error (that occurred on gcc-7):
error:
util/env_basic_test.cc: In member function 'virtual rocksdb::Status rocksdb::NormalizingEnvWrapper::GetChildren(const string&, std::vector<std::__cxx11::basic_string<char> >*)':
util/env_basic_test.cc:27:21: error: 'remove_if' is not a member of 'std'
result->erase(std::remove_if(result->begin(), result->end(),
^~~
Closes https://github.com/facebook/rocksdb/pull/1674
Differential Revision: D4331221
Pulled By: ajkr
fbshipit-source-id: 9bbdc78
Summary:
util/logging.cc💯13: error: output may be truncated before the last format character [-Werror=format-length=]
std::string NumberToHumanString(int64_t num) {
^~~~~~~~~~~~~~~~~~~
util/logging.cc:106:59: note: format output between 3 and 19 bytes into a destination of size 16
snprintf(buf, sizeof(buf), "%" PRIi64 "K", num / 1000);
Closes https://github.com/facebook/rocksdb/pull/1653
Differential Revision: D4318687
Pulled By: yiwu-arbug
fbshipit-source-id: 3a5c931
Summary:
Increased buffer size to 1650.
util/histogram.cc: In member function 'std::__cxx11::string rocksdb::HistogramStat::ToString() const':
util/histogram.cc:189:13: error: '%.2f' directive output truncated writing between 4 and 313 bytes into a region of size 0 [-Werror=format-length=]
std::string HistogramStat::ToString() const {
^~~~~~~~~~~~~
util/histogram.cc:205:30: note: format output between 69 and 1614 bytes into a destination of size 200
Percentile(99.99));
^
cc1plus: all warnings being treated as errors
Makefile:1521: recipe for target 'util/histogram.o' failed
Closes https://github.com/facebook/rocksdb/pull/1660
Differential Revision: D4318820
Pulled By: yiwu-arbug
fbshipit-source-id: 45ae6ea
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 is an implementation of non-exclusive locks for pessimistic transactions. It is relatively simple and does not prevent starvation (ie. it's possible that request for exclusive access will never be granted if there are always threads holding shared access). It is done by changing `KeyLockInfo` to hold an set a transaction ids, instead of just one, and adding a flag specifying whether this lock is currently held with exclusive access or not.
Some implementation notes:
- Some lock diagnostic functions had to be updated to return a set of transaction ids for a given lock, eg. `GetWaitingTxn` and `GetLockStatusData`.
- Deadlock detection is a bit more complicated since a transaction can now wait on multiple other transactions. A BFS is done in this case, and deadlock detection depth is now just a limit on the number of transactions we visit.
- Expirable transactions do not work efficiently with shared locks at the moment, but that's okay for now.
Closes https://github.com/facebook/rocksdb/pull/1573
Differential Revision: D4239097
Pulled By: lth
fbshipit-source-id: da7c074
Summary:
Made delete_obsolete_files_period_micros option dynamic. It can be updating using DB::SetDBOptions().
Closes https://github.com/facebook/rocksdb/pull/1595
Differential Revision: D4246569
Pulled By: tonek
fbshipit-source-id: d23f560
Summary:
Reduce number of comparisons in heap by caching which child node in the first level is smallest (left_child or right_child)
So next time we can compare directly against the smallest child
I see that the total number of calls to comparator drops significantly when using this optimization
Before caching (~2mil key comparison for iterating the DB)
```
$ DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readseq" --db="/dev/shm/heap_opt" --use_existing_db --disable_auto_compactions --cache_size=1000000000 --perf_level=2
readseq : 0.338 micros/op 2959201 ops/sec; 327.4 MB/s user_key_comparison_count = 2000008
```
After caching (~1mil key comparison for iterating the DB)
```
$ DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readseq" --db="/dev/shm/heap_opt" --use_existing_db --disable_auto_compactions --cache_size=1000000000 --perf_level=2
readseq : 0.309 micros/op 3236801 ops/sec; 358.1 MB/s user_key_comparison_count = 1000011
```
It also improves
Closes https://github.com/facebook/rocksdb/pull/1600
Differential Revision: D4256027
Pulled By: IslamAbdelRahman
fbshipit-source-id: 76fcc66
Summary:
disable UBSAN for functions with intentional left shift on -ve number / overflow
These functions are
rocksdb:: Hash
FixedLengthColBufEncoder::Append
FaultInjectionTest:: Key
Closes https://github.com/facebook/rocksdb/pull/1577
Differential Revision: D4240801
Pulled By: IslamAbdelRahman
fbshipit-source-id: 3e1caf6
Summary:
Having -ve value for max_write_buffer_number does not make sense and cause us to do a left shift on a -ve value number
Closes https://github.com/facebook/rocksdb/pull/1579
Differential Revision: D4240798
Pulled By: IslamAbdelRahman
fbshipit-source-id: bd6267e
Summary:
In one deployment we saw high latencies (presumably from slow iterator operations) and a lot of CPU time reported by perf with this stack:
```
rocksdb::MergingIterator::Next
rocksdb::DBIter::FindNextUserEntryInternal
rocksdb::DBIter::Seek
```
I think what's happening is:
1. we create a snapshot iterator,
2. we do lots of Put()s for the same key x; this creates lots of entries in memtable,
3. we seek the iterator to a key slightly smaller than x,
4. the seek walks over lots of entries in memtable for key x, skipping them because of high sequence numbers.
CC IslamAbdelRahman
Closes https://github.com/facebook/rocksdb/pull/1413
Differential Revision: D4083879
Pulled By: IslamAbdelRahman
fbshipit-source-id: a83ddae
Summary:
Current write stalling system has the problem of lacking of positive feedback if the restricted rate is already too low. Users sometimes stack in very low slowdown value. With the diff, we add a positive feedback (increasing the slowdown value) if we recover from slowdown state back to normal. To avoid the positive feedback to keep the slowdown value to be to high, we add issue a negative feedback every time we are close to the stop condition. Experiments show it is easier to reach a relative balance than before.
Also increase level0_stop_writes_trigger default from 24 to 32. Since level0_slowdown_writes_trigger default is 20, stop trigger 24 only gives four files as the buffer time to slowdown writes. In order to avoid stop in four files while 20 files have been accumulated, the slowdown value must be very low, which is amost the same as stop. It also doesn't give enough time for the slowdown value to converge. Increase it to 32 will smooth out the system.
Closes https://github.com/facebook/rocksdb/pull/1562
Differential Revision: D4218519
Pulled By: siying
fbshipit-source-id: 95e4088
Summary:
LZ4 1.7.3 emits warnings when calling the deprecated function `LZ4_compress_limitedOutput_continue()`. Starting in r129, LZ4 introduces `LZ4_compress_fast_continue()` as a replacement, and the two functions calls are [exactly equivalent](https://github.com/lz4/lz4/blob/dev/lib/lz4.c#L1408).
Closes https://github.com/facebook/rocksdb/pull/1532
Differential Revision: D4199240
Pulled By: siying
fbshipit-source-id: 138c2bc
Summary:
We should close the fd, before overriding it. This bug was
introduced by f89caa127b
Closes https://github.com/facebook/rocksdb/pull/1553
Differential Revision: D4214101
Pulled By: siying
fbshipit-source-id: 0d65de0
Summary:
- Made RangeDelAggregator's InternalKeyComparator member a reference-to-const so we don't need to copy-construct it. Also added InternalKeyComparator to ImmutableCFOptions so we don't need to construct one for each DBIter.
- Made MemTable::NewRangeTombstoneIterator and the table readers' NewRangeTombstoneIterator() functions return nullptr instead of NewEmptyInternalIterator to avoid the allocation. Updated callers accordingly.
Closes https://github.com/facebook/rocksdb/pull/1548
Differential Revision: D4208169
Pulled By: ajkr
fbshipit-source-id: 2fd65cf
Summary:
When calling StatisticsImpl::HistogramInfo::getMergedHistogram(), if
there is a dying thread, which is calling
ThreadLocalPtr::StaticMeta::OnThreadExit() to merge its thread values to
HistogramInfo, deadlock will occur. Because the former try to hold
merge_lock then ThreadMeta::mutex_, but the later try to hold
ThreadMeta::mutex_ then merge_lock. In short, the locking order isn't
the same.
This patch addressed this issue by releasing merge_lock before folding
thread values.
Closes https://github.com/facebook/rocksdb/pull/1552
Differential Revision: D4211942
Pulled By: ajkr
fbshipit-source-id: ef89bcb
Summary:
Currently, deadlock cycles are held in std::unordered_map. The problem with it is that it allocates/deallocates memory on every insertion/deletion. This limits throughput since we're doing this expensive operation while holding a global mutex. Fix this by using a vector which caches memory instead.
Running the deadlock stress test, this change increased throughput from 39k txns/s -> 49k txns/s. The effect is more noticeable in MyRocks.
Closes https://github.com/facebook/rocksdb/pull/1545
Differential Revision: D4205662
Pulled By: lth
fbshipit-source-id: ff990e4
Summary:
Currently, in the Direct I/O read mode, the last sector of the file, if not full, is not handled correctly. If the return value of pread is not multiplier of kSectorSize, we still go ahead and continue reading, even if the buffer is not aligned. With the commit, if the return value is not multiplier of kSectorSize, and all but the last sector has been read, we simply return.
Closes https://github.com/facebook/rocksdb/pull/1550
Differential Revision: D4209609
Pulled By: lightmark
fbshipit-source-id: cb0b439
Summary:
This patch clarifies the contract of PositionedAppend with some unit
tests and also implements it for PosixWritableFile. (Tasks: 14524071)
Closes https://github.com/facebook/rocksdb/pull/1514
Differential Revision: D4204907
Pulled By: maysamyabandeh
fbshipit-source-id: 06eabd2
Summary:
It is hard to measure acutal memory usage by std containers. Even
providing a custom allocator will miss count some of the usage. Here we
only do a wild guess on its memory usage.
Closes https://github.com/facebook/rocksdb/pull/1511
Differential Revision: D4179945
Pulled By: yiwu-arbug
fbshipit-source-id: 32ab929
Summary:
Currently our skip-list have an optimization to speedup sequential
inserts from a single stream, by remembering the last insert position.
We extend the idea to support sequential inserts from multiple streams,
and even tolerate small reordering wihtin each stream.
This PR is the interface part adding the following:
- Add `memtable_insert_prefix_extractor` to allow specifying prefix for each key.
- Add `InsertWithHint()` interface to memtable, to allow underlying
implementation to return a hint of insert position, which can be later
pass back to optimize inserts.
- Memtable will maintain a map from prefix to hints and pass the hint
via `InsertWithHint()` if `memtable_insert_prefix_extractor` is non-null.
Closes https://github.com/facebook/rocksdb/pull/1419
Differential Revision: D4079367
Pulled By: yiwu-arbug
fbshipit-source-id: 3555326
Summary:
This fixes a correctness issue where ranges with same begin key would overwrite each other.
This diff uses InternalKey as TombstoneMap's key such that all tombstones have unique keys even when their start keys overlap. We also update TombstoneMap to use an internal key comparator.
End-to-end tests pass and are here (https://gist.github.com/ajkr/851ffe4c1b8a15a68d33025be190a7d9) but cannot be included yet since the DeleteRange() API is yet to be checked in. Note both tests failed before this fix.
Closes https://github.com/facebook/rocksdb/pull/1484
Differential Revision: D4155248
Pulled By: ajkr
fbshipit-source-id: 304b4b9
Summary:
During Get()/MultiGet(), build up a RangeDelAggregator with range
tombstones as we search through live memtable, immutable memtables, and
SST files. This aggregator is then used by memtable.cc's SaveValue() and
GetContext::SaveValue() to check whether keys are covered.
added tests for Get on memtables/files; end-to-end tests mainly in https://reviews.facebook.net/D64761
Closes https://github.com/facebook/rocksdb/pull/1456
Differential Revision: D4111271
Pulled By: ajkr
fbshipit-source-id: 6e388d4
Summary:
DB Stats now are truncated if there are too many CFs. Extend the buffer size to allow more to be printed out. Also, separate out malloc to another log line.
Closes https://github.com/facebook/rocksdb/pull/1439
Differential Revision: D4100943
Pulled By: yiwu-arbug
fbshipit-source-id: 79f7218
Summary:
Rocksdb currently has many references to std::map.emplace_back()
which is not implemented in gcc 4.7, but valid in gcc 4.8. Confirmed that
it did not build with gcc 4.7, but builds fine with gcc 4.8
Closes https://github.com/facebook/rocksdb/pull/1272
Differential Revision: D4101385
Pulled By: IslamAbdelRahman
fbshipit-source-id: f6af453
* util/build_verion.cc.in: add this file, so cmake and make can share the
template file for generating util/build_version.cc.
* CMakeLists.txt: also, cmake v2.8.11 does not support file(GENERATE ...),
so we are using configure_file() for creating build_version.cc.
* Makefile: use util/build_verion.cc.in for creating build_version.cc.
Signed-off-by: Kefu Chai <tchaikov@gmail.com>
Summary: Using real clock causes failures of DBSSTTest.RateLimitedDelete in some cases. Turn away from the real time. Use fake time instead.
Test Plan: Run the tests and all existing tests.
Reviewers: yiwu, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D65145
Summary:
change ioptions.comparator to user_comparator instread of internal_comparator.
Also change Comparator* to InternalKeyComparator* to make its type explicitly.
Test Plan: make all check -j64
Reviewers: andrewkr, sdong, yiwu
Reviewed By: yiwu
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D65121
Summary:
reland https://reviews.facebook.net/D62523
- Update SstFileWriter to include a property for a global sequence number in the SST file `rocksdb.external_sst_file.global_seqno`
- Update TableProperties to be aware of the offset of each property in the file
- Update BlockBasedTableReader and Block to be able to honor the sequence number in `rocksdb.external_sst_file.global_seqno` property and use it to overwrite all sequence number in the file
Something worth mentioning is that we don't update the seqno in the index block since and when doing a binary search, the reason for that is that it's guaranteed that SST files with global seqno will have only one user_key and each key will have seqno=0 encoded in it, This mean that this key is greater than any other key with seqno> 0. That mean that we can actually keep the current logic for these blocks
Test Plan: unit tests
Reviewers: sdong, yhchiang
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D65211
