Summary:
There was an overflow bug when computing the variance in the HistogramStat class.
This manifests, for instance, when running cache_bench with default arguments. This executes 32M lookups/inserts/deletes in a block cache, and then computes (among other things) the variance of the latencies. The variance is computed as ``variance = (cur_sum_squares * cur_num - cur_sum * cur_sum) / (cur_num * cur_num)``, where ``cum_sum_squares`` is the sum of the squares of the samples, ``cur_num`` is the number of samples, and ``cur_sum`` is the sum of the samples. Because the median latency in a typical run is around 3800 nanoseconds, both the ``cur_sum_squares * cur_num`` and ``cur_sum * cur_sum`` terms overflow as uint64_t.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/10100
Test Plan: Added a unit test. Run ``make -j24 histogram_test && ./histogram_test``.
Reviewed By: pdillinger
Differential Revision: D36942738
Pulled By: guidotag
fbshipit-source-id: 0af5fb9e2a297a284e8e74c24e604d302906006e
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:
`valueIndexMap_` in histogram is redundant and search in `valueIndexMap_` is slower than search in `bucketValues_`.
this PR delete `valueIndexMap_` and search in `bucketValues_` by `std::lower_bound`
Pull Request resolved: https://github.com/facebook/rocksdb/pull/8625
Reviewed By: zhichao-cao
Differential Revision: D31613386
Pulled By: ajkr
fbshipit-source-id: d7415d724f5c8f41f80cbe82afd7467cfad6f009
Summary:
The dynamic_cast in the filter benchmark causes release mode to fail due to
no-rtti. Replace with static_cast_with_check.
Signed-off-by: Derrick Pallas <derrick@pallas.us>
Addition by peterd: Remove unnecessary 2nd template arg on all static_cast_with_check
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6732
Reviewed By: ltamasi
Differential Revision: D21304260
Pulled By: pdillinger
fbshipit-source-id: 6e8eb437c4ca5a16dbbfa4053d67c4ad55f1608c
Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433
Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.
Differential Revision: D19977691
fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e
Summary:
We see some odd errors complaining math. However, it doesn't seem that it is needed to be included. Remove the include of math.h. Just removing it from db_bench doesn't seem to break anything. Replacing sqrt from std::sqrt seems to work for histogram.cc
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6373
Test Plan: Watch Travis and appveyor to run.
Differential Revision: D19730068
fbshipit-source-id: d3ad41defcdd9f51c2da1a3673fb258f5dfacf47
Summary:
Further apply formatter to more recent commits.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5830
Test Plan: Run all existing tests.
Differential Revision: D17488031
fbshipit-source-id: 137458fd94d56dd271b8b40c522b03036943a2ab
Summary:
When using `PRIu64` type of printf specifier, current code base does the following:
```
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>
```
However, this can be simplified to
```
#include <cinttypes>
```
as long as flag `-std=c++11` is used.
This should solve issues like https://github.com/facebook/rocksdb/issues/5159
Pull Request resolved: https://github.com/facebook/rocksdb/pull/5402
Differential Revision: D15701195
Pulled By: miasantreble
fbshipit-source-id: 6dac0a05f52aadb55e9728038599d3d2e4b59d03
Summary:
Expose common stats min,max,count,sum via statistics JNI. These stats are not fully exposed on the Java side as is, but are available on the native side.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4742
Differential Revision: D13403766
Pulled By: ajkr
fbshipit-source-id: 5b70f7bd3fb7490aab73dcbd09f13490fce5c773
Summary:
Previously it only printed percentiles, even though our histogram keeps track of count and sum (and more). There have been many times we want to know more than the percentiles. For example, we currently want sum of "rocksdb.compression.times.nanos" and sum of "rocksdb.decompression.times.nanos", which would allow us to know the relative cost of compression vs decompression.
This PR adds count and sum to the string printed by `StatisticsImpl::ToString`. This is a bit risky as there are definitely parsers assuming the old format. I will mention it in HISTORY.md and hope for the best...
Closes https://github.com/facebook/rocksdb/pull/3863
Differential Revision: D8038831
Pulled By: ajkr
fbshipit-source-id: 0465b72e4b0cbf18ef965f4efe402601d16d5b5c
Summary:
The num() might return cur_num as 0 and we are making sure that
cur_num will not be 0 down the path. The mult variable is being set to
100.0/cur_num which makes program crash when cur_num is 0.
Closes https://github.com/facebook/rocksdb/pull/3105
Differential Revision: D6222594
Pulled By: ajkr
fbshipit-source-id: 986154709897ff4dbbeb0e8aa81eb8c0b2a2db76
Summary:
I spent too much time thinking about histograms lately and realized boundary values fall into the lower bucket, not the upper bucket. It's because we're using `std::map::lower_bound` here: 867fe92e5e/monitoring/histogram.cc (L53). Fixed histogram's `ToString()` to reflect this.
Closes https://github.com/facebook/rocksdb/pull/2817
Differential Revision: D5751159
Pulled By: ajkr
fbshipit-source-id: 67432bb45849eec9b5bcc0d095551dbc0ee81766
Summary:
The goal is to reduce the number of histogram buckets, particularly now that we print these histograms for each column family. I chose 1.5 as the factor. We can adjust it later to either make buckets more granular or make fewer buckets.
Closes https://github.com/facebook/rocksdb/pull/2139
Differential Revision: D4872076
Pulled By: ajkr
fbshipit-source-id: 87790d782a605506c3d24190a028cecbd7aa564a
Summary:
sounds like we're willing to tradeoff minor inaccuracy in stats for speed. start with histogram stats. ticker stats will be harder (and, IMO, we shouldn't change them in this manner) as many test cases rely on them being exactly correct.
Closes https://github.com/facebook/rocksdb/pull/2720
Differential Revision: D5607884
Pulled By: ajkr
fbshipit-source-id: 1b754cda35ea6b252d1fdd5aa3cfb58866506372
Summary:
Replace dynamic_cast<> so that users can choose to build with RTTI off, so that they can save several bytes per object, and get tiny more memory available.
Some nontrivial changes:
1. Add Comparator::GetRootComparator() to get around the internal comparator hack
2. Add the two experiemental functions to DB
3. Add TableFactory::GetOptionString() to avoid unnecessary casting to get the option string
4. Since 3 is done, move the parsing option functions for table factory to table factory files too, to be symmetric.
Closes https://github.com/facebook/rocksdb/pull/2645
Differential Revision: D5502723
Pulled By: siying
fbshipit-source-id: fd13cec5601cf68a554d87bfcf056f2ffa5fbf7c
Summary:
Move some files under util/ to new directories env/, monitoring/ options/ and cache/
Closes https://github.com/facebook/rocksdb/pull/2090
Differential Revision: D4833681
Pulled By: siying
fbshipit-source-id: 2fd8bef
Summary:
Without the cast, the build will break on Windows.
Closes https://github.com/facebook/rocksdb/pull/1982
Differential Revision: D4690462
Pulled By: ajkr
fbshipit-source-id: c493b6c
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:
Two fixes:
1. Wait compaction after generating each L0 file so that we are sure there are one L0 file left.
2. https://reviews.facebook.net/D48423 increased from 500 keys to 700 keys but in verification phase we are still querying the first 500 keys. It is a bug to fix.
Test Plan: Run the test in the same environment that fails by chance of one in tens of times. It doesn't fail after 1000 times.
Reviewers: yhchiang, IslamAbdelRahman, igor, rven, kradhakrishnan
Reviewed By: rven, kradhakrishnan
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48759
Summary: So iOS size_t is 32-bit, so we need to static_cast<size_t> any uint64_t :(
Test Plan: TARGET_OS=IOS make static_lib
Reviewers: dhruba, ljin, yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D28743
1, const qualifiers on return types make no sense and will trigger a compile warning: warning: type qualifiers ignored on function return type [-Wignored-qualifiers]
2, class HistogramImpl has virtual functions and thus should have a virtual destructor
3, with some toolchain, the macro __STDC_FORMAT_MACROS is predefined and thus should be checked before define
Change-Id: I69747a03bfae88671bfbb2637c80d17600159c99
Signed-off-by: liuhuahang <liuhuahang@zerus.co>
Summary: I'm separating code-cleanup part of https://reviews.facebook.net/D14517. This will make D14517 easier to understand and this diff easier to review.
Test Plan: make check
Reviewers: haobo, kailiu, sdong, dhruba, tnovak
Reviewed By: tnovak
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15099
Summary:
mac and our dev server has totally differnt definition of uint64_t, therefore fixing the warning in mac has actually made code in linux uncompileable.
Test Plan:
make clean && make -j32
Summary: The work to make sure mac os compiles rocksdb is not completed yet. But at least we can start cleaning some warnings captured only by g++ from mac os..
Test Plan: ran make in mac os
Reviewers: dhruba
Reviewed By: dhruba
CC: leveldb
Differential Revision: https://reviews.facebook.net/D14049
Summary:
Change namespace from leveldb to rocksdb. This allows a single
application to link in open-source leveldb code as well as
rocksdb code into the same process.
Test Plan: compile rocksdb
Reviewers: emayanke
Reviewed By: emayanke
CC: leveldb
Differential Revision: https://reviews.facebook.net/D13287
Summary: Statistics.h and histogram.h had double based api's to record values. Remove them as they are not used anywhere
Test Plan: make all check
Reviewers: haobo, dhruba
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D10815
Summary:
Adds the --writes_per_second rate limit for the readwhilewriting test.
The purpose is to optionally avoid saturating storage with writes & compaction
and test read response time when some writes are being done.
Changes the histogram code to also print the p99.99 value
Task ID: #
Blame Rev:
Test Plan:
make check, ran db_bench with it
Revert Plan:
Database Impact:
Memcache Impact:
Other Notes:
EImportant:
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: haobo
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D10305
Summary: Makefile had options to ignore sign-comparisons and unused-parameters, which should be there. Also fixed the specific errors in the code-base
Test Plan: make
Reviewers: chip, dhruba
Reviewed By: dhruba
CC: leveldb
Differential Revision: https://reviews.facebook.net/D9531
Summary:
* Introduce is histogram in statistics.h
* stop watch to measure time.
* introduce two timers as a poc.
Replaced NULL with nullptr to fight some lint errors
Should be useful for google.
Test Plan:
ran db_bench and check stats.
make all check
Reviewers: dhruba, heyongqiang
Reviewed By: dhruba
CC: leveldb
Differential Revision: https://reviews.facebook.net/D8637
Summary:
$SUBJECT -- cosmetic fix for histograms, print P75/P99, and
make sure zlib is enabled for our command line tools.
Test Plan: compile, test db_bench with --compression_type=zlib
Reviewers: heyongqiang
Reviewed By: heyongqiang
CC: adsharma, leveldb
Differential Revision: https://reviews.facebook.net/D8445
Summary:
The existing code did not initialize a few doubles in histogram.cc.
Cropped up when I wrote a unit-test.
Test Plan: make all check
Reviewers: chip
Reviewed By: chip
CC: leveldb
Differential Revision: https://reviews.facebook.net/D8319
Summary:
Earlier way to record in histogram=>
Linear search BucketLimit array to find the bucket and increment the
counter
Current way to record in histogram=>
Store a HistMap statically which points the buckets of each value in the
range [kFirstValue, kLastValue);
In the proccess use vectors instead of array's and refactor some code to
HistogramHelper class.
Test Plan:
run db_bench with histogram=1 and see a histogram being
printed.
Reviewers: dhruba, chip, heyongqiang
Reviewed By: chip
CC: leveldb
Differential Revision: https://reviews.facebook.net/D8265
- Replace raw slice comparison with a call to user comparator.
Added test for custom comparators.
- Fix end of namespace comments.
- Fixed bug in picking inputs for a level-0 compaction.
When finding overlapping files, the covered range may expand
as files are added to the input set. We now correctly expand
the range when this happens instead of continuing to use the
old range. For example, suppose L0 contains files with the
following ranges:
F1: a .. d
F2: c .. g
F3: f .. j
and the initial compaction target is F3. We used to search
for range f..j which yielded {F2,F3}. However we now expand
the range as soon as another file is added. In this case,
when F2 is added, we expand the range to c..j and restart the
search. That picks up file F1 as well.
This change fixes a bug related to deleted keys showing up
incorrectly after a compaction as described in Issue 44.
(Sync with upstream @25072954)
- Fix for issue 33 (non-null-terminated result from
leveldb_property_value())
- Support for running multiple instances of a benchmark in parallel.
- Reduce lock contention on Get():
(1) Do not hold the lock while searching memtables.
(2) Shard block and table caches 16-ways.
Benchmark for evaluating this change:
$ db_bench --benchmarks=fillseq1,readrandom --threads=$n
(fillseq1 is a small hack to make sure fillseq runs once regardless
of number of threads specified on the command line).
git-svn-id: https://leveldb.googlecode.com/svn/trunk@49 62dab493-f737-651d-591e-8d6aee1b9529
Guido Tagliavini Ponce