Commit graph

1393 commits

Author SHA1 Message Date
Siying Dong f289d9f4ac Fix OSX build break after the fallocate change
Summary:
The recent update about fallocate failed OSX build. Fix it.
Closes https://github.com/facebook/rocksdb/pull/1830

Differential Revision: D4500235

Pulled By: siying

fbshipit-source-id: a5f2b40
2017-02-02 10:39:11 -08:00
Siying Dong 4a3e7d320c Change the default of delayed slowdown value to 16MB/s
Summary:
Change the default of delayed slowdown value to 16MB/s and further increase the L0 stop condition to 36 files.
Closes https://github.com/facebook/rocksdb/pull/1821

Differential Revision: D4489229

Pulled By: siying

fbshipit-source-id: 1003981
2017-02-01 20:39:17 -08:00
Siying Dong 0513e21f9b RangeSync() should work with ROCKSDB_FALLOCATE_PRESENT not set
Summary: Closes https://github.com/facebook/rocksdb/pull/1824

Differential Revision: D4493862

Pulled By: siying

fbshipit-source-id: c168446
2017-02-01 10:24:20 -08:00
Islam AbdelRahman 8b369ae5bd Cleaner default options using C++11 in-class init
Summary:
C++11 in-class initialization is cleaner and makes it the default more explicit to our users and more visible.
Use it for ColumnFamilyOptions and DBOptions
Closes https://github.com/facebook/rocksdb/pull/1822

Differential Revision: D4490473

Pulled By: IslamAbdelRahman

fbshipit-source-id: c493a87
2017-01-31 18:09:15 -08:00
Islam AbdelRahman ec79a7b53c Dedup code in option.cc and db_options.cc
Summary:
The code in DBOptions::Dump is simply a duplicate of the code in ImmutableDBOptions::Dump and MutableDBOptions.Dump

consolidate duplicate code.

tested visually
Closes https://github.com/facebook/rocksdb/pull/1818

Differential Revision: D4486710

Pulled By: IslamAbdelRahman

fbshipit-source-id: 7085189
2017-01-31 17:39:12 -08:00
Siying Dong 2d75cd40d3 NewLRUCache() to pick number of shard bits based on capacity if not given
Summary:
If the users use the NewLRUCache() without passing in the number of shard bits, instead of using hard-coded 6, we'll determine it based on capacity.
Closes https://github.com/facebook/rocksdb/pull/1584

Differential Revision: D4242517

Pulled By: siying

fbshipit-source-id: 86b0f18
2017-01-27 06:39:12 -08:00
Andrew Kryczka 94a0c32e73 Fix LRU Ref() for handles with external references only
Summary:
For case !handle->InCache() && handle->refs >= 1 (the third case mentioned in lru_cache.h), the key was overwritten by Insert(). In this case, the refcount can still be incremented, and the cache handle will never enter LRU list. Fix Ref() logic for this case.
Closes https://github.com/facebook/rocksdb/pull/1808

Differential Revision: D4467656

Pulled By: ajkr

fbshipit-source-id: c0784d8
2017-01-26 10:54:15 -08:00
Andrew Kryczka 17c1180603 Generalize Env registration framework
Summary:
The Env registration framework supports registering client Envs and selecting which one to instantiate according to a text field. This enabled things like adding the -env_uri argument to db_bench, so the same binary could be reused with different Envs just by changing CLI config.

Now this problem has come up again in a non-Env context, as I want to instantiate a client Statistics implementation from db_bench, which is configured entirely via text parameters. Also, in the future we may wish to use it for deserializing client objects when loading OPTIONS file.

This diff generalizes the Env registration logic to work with arbitrary types.

- Generalized registration and instantiation code by templating them
- The entire implementation is in a header file as that's Google style guide's recommendation for template definitions
- Pattern match with std::regex_match rather than checking prefix, which was the previous behavior
- Rename functions/files to be non-Env-specific
Closes https://github.com/facebook/rocksdb/pull/1776

Differential Revision: D4421933

Pulled By: ajkr

fbshipit-source-id: 34647d1
2017-01-25 16:09:14 -08:00
sdong 07dddd5f7e EnvPosixTestWithParam should wait for all threads to finish
Summary:
If we don't wait for the threads to finish after each run, the thread queue may not be empty while the next test starts to run, which can cause unexpected behaviors.

Also make some of the relaxed read/write more restrict.
Closes https://github.com/facebook/rocksdb/pull/1590

Reviewed By: AsyncDBConnMarkedDownDBException

Differential Revision: D4245922

Pulled By: AsyncDBConnMarkedDownDBException

fbshipit-source-id: f83b74b
2017-01-25 15:54:13 -08:00
Hyeonseok Oh f2b4939da4 fixed typo
Summary:
I fixed exisit -> exist
Closes https://github.com/facebook/rocksdb/pull/1799

Differential Revision: D4451466

Pulled By: yiwu-arbug

fbshipit-source-id: b447c3a
2017-01-23 12:54:13 -08:00
Siying Dong 0e8dfd6062 Fix OptimizeForPointLookup()
Summary:
If users directly call OptimizeForPointLookup(), it is broken as the option isn't compatible with parallel memtable insert. Fix it by using memtable bloomo filter instead.
Closes https://github.com/facebook/rocksdb/pull/1791

Differential Revision: D4442836

Pulled By: siying

fbshipit-source-id: bf6c9cd
2017-01-20 10:54:12 -08:00
Yi Wu 9239103cd4 Flush job should release reference current version if sync log failed
Summary:
Fix the bug when sync log fail, FlushJob::Run() will not be execute and
reference to cfd->current() will not be release.
Closes https://github.com/facebook/rocksdb/pull/1792

Differential Revision: D4441316

Pulled By: yiwu-arbug

fbshipit-source-id: 5523e28
2017-01-19 23:09:15 -08:00
Yi Wu 602c13a964 Remove fadvise with direct IO read
Summary:
Remove the logic since we don't use buffer cache with direct IO. Resolve
read regression we currently have.
Closes https://github.com/facebook/rocksdb/pull/1782

Differential Revision: D4430408

Pulled By: yiwu-arbug

fbshipit-source-id: 5557bba
2017-01-18 12:09:10 -08:00
Kefu Chai e8a096000b util/thread_local.h: silence a clang-build warning
Summary:
otherwise clang complains with

/home/jenkins/workspace/ceph-master/src/rocksdb/util/thread_local.h:205:5:
error: macro expansion producing 'defined' has undefined behavior
[-Werror,-Wexpansion-to-defined]
^
/home/jenkins/workspace/ceph-master/src/rocksdb/util/thread_local.h:22:4:
note: expanded from macro 'ROCKSDB_SUPPORT_THREAD_LOCAL'
!defined(OS_WIN) && !defined(OS_MACOSX) && !defined(IOS_CROSS_COMPILE)
^`

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
Closes https://github.com/facebook/rocksdb/pull/1757

Differential Revision: D4394140

Pulled By: siying

fbshipit-source-id: f0beda0
2017-01-15 13:24:16 -08:00
Aaron Gao 3e6899d116 change UseDirectIO() to use_direct_io()
Summary:
also change variable name `direct_io_` to `use_direct_io_` in WritableFile to make it consistent with read path.
Closes https://github.com/facebook/rocksdb/pull/1770

Differential Revision: D4416435

Pulled By: lightmark

fbshipit-source-id: 4143c53
2017-01-13 12:09:15 -08:00
Aaron Gao d4e07a8459 fix warning of unused direct io helper functions
Summary:
add build guard
Closes https://github.com/facebook/rocksdb/pull/1771

Differential Revision: D4410779

Pulled By: siying

fbshipit-source-id: 3796c30
2017-01-12 12:39:14 -08:00
Aaron Gao dc2584eea0 direct reads refactor
Summary:
direct IO reads refactoring
remove unnecessary classes and unified interfaces
tested with db_bench

need more change for options and ON/OFF for different files.
Since disabled is default, it should be fine now
Closes https://github.com/facebook/rocksdb/pull/1636

Differential Revision: D4307189

Pulled By: lightmark

fbshipit-source-id: 6991e22
2017-01-11 16:54:12 -08:00
Anirban Rahut 62384ebe9c Guarding extra fallocate call with TRAVIS because its not working pro…
Summary:
…perly on travis

 There is some old code in PosixWritableFile::Close(), which
truncates the file to the measured size and then does an extra fallocate
with KEEP_SIZE. This is commented as a failsafe because in some
cases ftruncate doesn't do the right job (I don't know of an instance of
this btw). However doing an fallocate with KEEP_SIZE should not increase
the file size. However on Travis Worker which is Docker (likely AUFS )
its not working. There are comments on web that show that the AUFS
author had initially not implemented fallocate, and then did it later.
So not sure what is the quality of the implementation.
Closes https://github.com/facebook/rocksdb/pull/1765

Differential Revision: D4401340

Pulled By: anirbanr-fb

fbshipit-source-id: e2d8100
2017-01-11 14:24:13 -08:00
Andrew Kryczka fe395fb63d Allow incrementing refcount on cache handles
Summary:
Previously the only way to increment a handle's refcount was to invoke Lookup(), which (1) did hash table lookup to get cache handle, (2) incremented that handle's refcount. For a future DeleteRange optimization, I added a function, Ref(), for when the caller already has a cache handle and only needs to do (2).
Closes https://github.com/facebook/rocksdb/pull/1761

Differential Revision: D4397114

Pulled By: ajkr

fbshipit-source-id: 9addbe5
2017-01-10 16:54:20 -08:00
Dmitri Smirnov 3c233ca4ea Fix Windows environment issues
Summary:
Enable directIO on WritableFileImpl::Append
     with offset being current length of the file.
     Enable UniqueID tests on Windows, disable others but
     leeting them to compile. Unique tests are valuable to
     detect failures on different filesystems and upcoming
     ReFS.
     Clear output in WinEnv Getchildren.This is different from
     previous strategy, do not touch output on failure.
     Make sure DBTest.OpenWhenOpen works with windows error message
Closes https://github.com/facebook/rocksdb/pull/1746

Differential Revision: D4385681

Pulled By: IslamAbdelRahman

fbshipit-source-id: c07b702
2017-01-09 15:54:12 -08:00
Maysam Yabandeh d0ba8ec8f9 Revert "PinnableSlice"
Summary:
This reverts commit 54d94e9c2c.

The pull request was landed by mistake.
Closes https://github.com/facebook/rocksdb/pull/1755

Differential Revision: D4391678

Pulled By: maysamyabandeh

fbshipit-source-id: 36d5149
2017-01-08 14:24:12 -08:00
Maysam Yabandeh 54d94e9c2c PinnableSlice
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
2017-01-08 13:54:13 -08:00
Islam AbdelRahman ac73d7558b Add GetSupportedCompressions() convenience function
Summary:
This function will return a list of supported compression types in RocksDB
This is needed for MyRocks https://github.com/facebook/mysql-5.6/pull/446
Closes https://github.com/facebook/rocksdb/pull/1747

Differential Revision: D4385921

Pulled By: IslamAbdelRahman

fbshipit-source-id: 2f5b59f
2017-01-06 11:24:14 -08:00
Adam Retter 85ac1a320a Fix rocksdb::Status::getState
Summary:
This fixes the Java API for Status#getState use in Native code and also simplifies the implementation of rocksdb::Status::getState.
Closes https://github.com/facebook/rocksdb/issues/1688
Closes https://github.com/facebook/rocksdb/pull/1714

Differential Revision: D4364181

Pulled By: yiwu-arbug

fbshipit-source-id: 8e073b4
2017-01-03 18:39:14 -08:00
Siying Dong 17a4b75cc3 Always fsync the file after file copying
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
2016-12-28 19:09:16 -08:00
Yi Wu ab48c165a9 Print cache options to info log
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
2016-12-22 14:54:19 -08:00
Aaron Gao 972f96b3fb direct io write support
Summary:
rocksdb direct io support

```
[gzh@dev11575.prn2 ~/rocksdb] ./db_bench -benchmarks=fillseq --num=1000000
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
RocksDB:    version 5.0
Date:       Wed Nov 23 13:17:43 2016
CPU:        40 * Intel(R) Xeon(R) CPU E5-2660 v2 @ 2.20GHz
CPUCache:   25600 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    1000000
Prefix:    0 bytes
Keys per prefix:    0
RawSize:    110.6 MB (estimated)
FileSize:   62.9 MB (estimated)
Write rate: 0 bytes/second
Compression: Snappy
Memtablerep: skip_list
Perf Level: 1
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
Initializing RocksDB Options from the specified file
Initializing RocksDB Options from command-line flags
DB path: [/tmp/rocksdbtest-112628/dbbench]
fillseq      :       4.393 micros/op 227639 ops/sec;   25.2 MB/s

[gzh@dev11575.prn2 ~/roc
Closes https://github.com/facebook/rocksdb/pull/1564

Differential Revision: D4241093

Pulled By: lightmark

fbshipit-source-id: 98c29e3
2016-12-22 13:09:19 -08:00
Islam AbdelRahman 989e644ed8 Remove sst_file_manager option from LITE
Summary:
Remove sst_file_manager option from LITE
Closes https://github.com/facebook/rocksdb/pull/1690

Differential Revision: D4341331

Pulled By: IslamAbdelRahman

fbshipit-source-id: 9f9328d
2016-12-21 17:54:21 -08:00
Jianpeng Ma bd6cf7b51d WritableFileWriter: default buffer size equal min(64k,options.writabl?
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
2016-12-16 13:09:14 -08:00
Daniel Black 816c1e30ca gcc-7 requires include <functional> for std::function
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
2016-12-16 11:24:18 -08:00
Daniel Black 0ab6fc167f Gcc-7 buffer size insufficient
Summary:
Bunch of commits related to insufficient buffer size. Errors in individual commits.
Closes https://github.com/facebook/rocksdb/pull/1673

Differential Revision: D4332127

Pulled By: IslamAbdelRahman

fbshipit-source-id: 878f73c
2016-12-14 19:24:26 -08:00
Daniel Black b7239bf7e0 Gcc 7 fallthrough
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
2016-12-14 19:24:25 -08:00
Daniel Black 477b6ea578 std::remove_if requires <algorithm>
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
2016-12-14 17:09:14 -08:00
Daniel Black e097222e64 util/logging.cc: buffer of insufficient size (gcc-7 -Werror=format-length)
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
2016-12-13 18:39:14 -08:00
Daniel Black bfbcec2339 Gcc 7 error expansion to defined
Summary:
sorry if these gcc-7/clang-4 cleanups are getting tedious.
Closes https://github.com/facebook/rocksdb/pull/1658

Differential Revision: D4318792

Pulled By: yiwu-arbug

fbshipit-source-id: 8e85891
2016-12-13 18:39:14 -08:00
Daniel Black c3e5ee7154 util/histogram.cc: HistogramStat::toString buffer insufficient
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
2016-12-13 14:09:12 -08:00
Andrew Kryczka f0c509e2c8 Return finer-granularity status from Env::GetChildren*
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
2016-12-12 12:54:13 -08:00
Manuel Ung 2005c88a75 Implement non-exclusive locks
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
2016-12-05 17:39:17 -08:00
Anton Safonov 9053fe2a5c Made delete_obsolete_files_period_micros option dynamic
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
2016-12-05 14:24:16 -08:00
Islam AbdelRahman 4a21b1402c Cache heap::downheap() root comparison (optimize heap cmp call)
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
2016-12-01 13:39:14 -08:00
Islam AbdelRahman e39d080871 Fix travis (compile for clang < 3.9)
Summary:
Travis fail because it uses clang 3.6 which don't recognize
`__attribute__((__no_sanitize__("undefined")))`
Closes https://github.com/facebook/rocksdb/pull/1601

Differential Revision: D4257175

Pulled By: IslamAbdelRahman

fbshipit-source-id: fb4d1ab
2016-12-01 10:09:22 -08:00
Islam AbdelRahman 52fd1ff2c2 disable UBSAN for functions with intentional -ve shift / overflow
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
2016-11-28 17:54:12 -08:00
Islam AbdelRahman 63c30de80d fix options_test ubsan
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
2016-11-28 16:39:14 -08:00
Mike Kolupaev 236d4c67e9 Less linear search in DBIter::Seek() when keys are overwritten a lot
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
2016-11-28 10:24:11 -08:00
Siying Dong cd7c4143d7 Improve Write Stalling System
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
2016-11-23 09:24:15 -08:00
Nick Terrell 4444256ab7 Remove use of deprecated LZ4 function
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
2016-11-21 12:24:14 -08:00
Changli Gao 548d7fb261 Fix fd leak when using direct IOs
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
2016-11-21 12:24:13 -08:00
Andrew Kryczka fd43ee09da Range deletion microoptimizations
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
2016-11-21 12:24:13 -08:00
Changli Gao a0deec960f Fix deadlock when calling getMergedHistogram
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
2016-11-20 18:24:12 -08:00
Manuel Ung e63350e726 Use more efficient hash map for deadlock detection
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
2016-11-19 11:39:15 -08:00