Commit Graph

547 Commits

Author SHA1 Message Date
Dhruba Borthakur
c0ce562c32 Bad nfs file checked in a long time back.
Summary:
Bad nfs file checked in a long time back.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-10 22:00:49 -07:00
Mayank Agarwal
a8b4a69de0 Fixing error in ParseFileName causing DestroyDB to fail on archive directory
Summary:
This careless error was causing ASSERT_OK(DestroyDB) to fail in db_test.
Basically .. was being returned as a child of db/archive and ParseFileName returned false on that,
but 'type' was set to LogFile from earlier and not reset. The return of ParseFileName was not being checked to delete the log file or not.

Test Plan: make all check

Reviewers: dhruba, haobo, xjin, kailiu, nkg-

Reviewed By: nkg-

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13413
2013-10-10 18:18:31 -07:00
Naman Gupta
cbf4a06427 Add option for storing transaction logs in a separate dir
Summary: In some cases, you might not want to store the data log (write ahead log) files in the same dir as the sst files. An example use case is leaf, which stores sst files in tmpfs. And would like to save the log files in a separate dir (disk) to save memory.

Test Plan: make all. Ran db_test test. A few test failing. P2785018. If you guys don't see an obvious problem with the code, maybe somebody from the rocksdb team could help me debug the issue here. Running this on leaf worked well. I could see logs stored on disk, and deleted appropriately after compactions. Obviously this is only one set of options. The unit tests cover different options. Seems like I'm missing some edge cases.

Reviewers: dhruba, haobo, leveldb

CC: xinyaohu, sumeet

Differential Revision: https://reviews.facebook.net/D13239
2013-10-08 17:40:27 -07:00
Naman Gupta
116071411b Make db_test more robust
Summary: While working on D13239, I noticed that the same options are not used for opening and destroying at db. So adding that. Also added asserts for successful DestroyDB calls.

Test Plan: Ran unit tests. Atleast 1 unit test is failing. They failures are a result of some past logic change. I'm not really planning to fix those. But I would like to check this in. And hopefully the respective unit test owners can fix the broken tests

Reviewers: leveldb, haobo

CC: xinyaohu, sumeet, dhruba

Differential Revision: https://reviews.facebook.net/D13329
2013-10-08 13:19:31 -07:00
Dhruba Borthakur
1a8c1b0817 Unit test failure in DBTest.NumImmutableMemTable.
Summary:
Previous patch introduced a unit test failure in
DBTest.NumImmutableMemTable because of change in property names.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-10-06 01:12:02 -07:00
Dhruba Borthakur
4463b11cad Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.
Summary: Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.

Test Plan: make check

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13311
2013-10-06 00:14:26 -07:00
Haobo Xu
bf89edf78b [RocksDB] Added a property "leveldb.num-immutable-mem-table" so that Flush can be called without blocking, and application still has a way to check when it's done also without blocking.
Summary: as title

Test Plan: DBTest.NumImmutableMemTable

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13305
2013-10-05 11:54:08 -07:00
Dhruba Borthakur
0a9f873f4b Removed scribe, thrift and java modules.
Summary: Removed scribe, thrift and java modules.

Test Plan:
make release
make check

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13293
2013-10-04 15:36:00 -07:00
Dhruba Borthakur
a143ef9b38 Change namespace from leveldb to rocksdb
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
2013-10-04 11:59:26 -07:00
Mayank Agarwal
b3ed08129b Add a statistic to count the number of calls to GetUpdatesSince
Summary: This is useful to keep track of refreshes in transaction log iterator

Test Plan: make; db_stress --statistics=1 shows it

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13281
2013-10-04 10:47:20 -07:00
Mayank Agarwal
854d236361 Add backward compatible option in GetLiveFiles to choose whether to not Flush first
Summary:
As explained in comments in GetLiveFiles in db.h, this option will cause flush to be skipped in GetLiveFiles because some use-cases use GetSortedWalFiles after GetLiveFiles to generate more complete snapshots.
Using GetSortedWalFiles after GetLiveFiles allows us to not Flush in GetLiveFiles first because wals have everything.
Note: file deletions will be disabled before calling GLF or GSWF so live logs will not move to archive logs or get delted.
Note: Manifest file is truncated to a proper value in GLF, so it will always reply from the proper wal files on a restart

Test Plan: make

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13257
2013-10-04 10:20:10 -07:00
Haobo Xu
200c05a23f [RocksDB] Still honor DisableFileDeletions when purge_log_after_memtable_flush is on
Summary: as title

Test Plan: make check

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13263
2013-10-03 16:12:43 -07:00
Haobo Xu
fa798e9e28 [Rocksdb] Submit mem table flush job in a different thread pool
Summary: As title. This is just a quick hack and not ready for commit. fails a lot of unit test. I will test/debug it directly in ViewState shadow .

Test Plan: Try it in shadow test.

Reviewers: dhruba, xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12933
2013-10-03 14:37:19 -07:00
Xing Jin
658a3ce2fa Fix SIGSEGV issue in universal compaction
Summary:
We saw SIGSEGV when set options.num_levels=1 in universal compaction
style. Dug into this issue for a while, and finally found the root cause (thank Haobo for discussion).

Test Plan: Add new unit test. It throws SIGSEGV without this change. Also run "make all check".

Reviewers: haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13251
2013-10-02 17:33:31 -07:00
Haobo Xu
71046971f0 [RocksDB] Added perf counters to track skipped internal keys during iteration
Summary: as title. unit test not polished. this is for a quick live test

Test Plan: live

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13221
2013-10-02 10:48:41 -07:00
Xing Jin
8eb552bf4d New unit test for iterator with snapshot
Summary:
I played with the reported bug about iterator with snapshot:
https://code.google.com/p/leveldb/issues/detail?id=200.

I turned the original test program
(https://code.google.com/p/leveldb/issues/attachmentText?id=200&aid=2000000000&name=test.cc&token=7uOUQW-HFlbAFMUm7EqtaAEy7Tw%3A1378320724136)
into a new unit test, but I cannot reproduce the problem. Notice lines
31-34 in above link. I have ran the new test with and without such Put()
operations. Both succeed.

So this diff simply adds the test, without changing any source codes.

Test Plan: run new test.

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12735
2013-09-28 11:39:08 -07:00
Haobo Xu
0c4040681a [RocksDB] Move last_sequence and last_flushed_sequence_ update back into lock protected area
Summary: A previous diff moved these outside of lock protected area. Moved back in now. Also moved tmp_batch_ update outside of lock protected area, as only the single write thread can access it.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13137
2013-09-26 20:43:11 -07:00
Haobo Xu
08740b15a4 [RocksDB] Fix skiplist sequential insertion optimization
Summary: The original optimization missed updating links other than the lowest level.

Test Plan: make check; perf_context_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, adsharma

Differential Revision: https://reviews.facebook.net/D13119
2013-09-26 15:17:03 -07:00
Haobo Xu
e0aa19a94e [RocbsDB] Add an option to enable set based memtable for perf_context_test
Summary:
as title.
Some result:

-- Sequential insertion of 1M key/value with stock skip list (all in on memtable)
time ./perf_context_test  --total_keys=1000000  --use_set_based_memetable=0
Inserting 1000000 key/value pairs
...
Put uesr key comparison:
Count: 1000000  Average: 8.0179  StdDev: 176.34
Min: 0.0000  Median: 2.5555  Max: 88933.0000
Percentiles: P50: 2.56 P75: 2.83 P99: 58.21 P99.9: 133.62 P99.99: 987.50
Get uesr key comparison:
Count: 1000000  Average: 43.4465  StdDev: 379.03
Min: 2.0000  Median: 36.0195  Max: 88939.0000
Percentiles: P50: 36.02 P75: 43.66 P99: 112.98 P99.9: 824.84 P99.99: 7615.38
real	0m21.345s
user	0m14.723s
sys	0m5.677s

-- Sequential insertion of 1M key/value with set based memtable (all in on memtable)
time ./perf_context_test  --total_keys=1000000  --use_set_based_memetable=1
Inserting 1000000 key/value pairs
...
Put uesr key comparison:
Count: 1000000  Average: 61.5022  StdDev: 6.49
Min: 0.0000  Median: 62.4295  Max: 71.0000
Percentiles: P50: 62.43 P75: 66.61 P99: 71.00 P99.9: 71.00 P99.99: 71.00
Get uesr key comparison:
Count: 1000000  Average: 29.3810  StdDev: 3.20
Min: 1.0000  Median: 29.1801  Max: 34.0000
Percentiles: P50: 29.18 P75: 32.06 P99: 34.00 P99.9: 34.00 P99.99: 34.00
real	0m28.875s
user	0m21.699s
sys	0m5.749s

Worst case comparison for a Put is 88933 (skiplist) vs 71 (set based memetable)

Of course, there's other in-efficiency in set based memtable implementation, which lead to the overall worst performance. However, P99 behavior advantage is very very obvious.

Test Plan: ./perf_context_test and viewstate shadow testing

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13095
2013-09-25 22:49:18 -07:00
Dhruba Borthakur
f1a60e5c3e The vector rep implementation was segfaulting because of incorrect initialization of vector.
Summary:
The constructor for Vector memtable has a parameter called 'count'
that specifies the capacity of the vector to be reserved at allocation
time. It was incorrectly used to initialize the size of the vector.

Test Plan: Enhanced db_test.

Reviewers: haobo, xjin, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13083
2013-09-25 11:33:52 -07:00
Dhruba Borthakur
5e9f3a9aa7 Better locking in vectorrep that increases throughput to match speed of storage.
Summary:
There is a use-case where we want to insert data into rocksdb as
fast as possible. Vector rep is used for this purpose.

The background flush thread needs to flush the vectorrep to
storage. It acquires the dblock then sorts the vector, releases
the dblock and then writes the sorted vector to storage. This is
suboptimal because the lock is held during the sort, which
prevents new writes for occuring.

This patch moves the sorting of the vector rep to outside the
db mutex. Performance is now as fastas the underlying storage
system. If you are doing buffered writes to rocksdb files, then
you can observe throughput upwards of 200 MB/sec writes.

This is an early draft and not yet ready to be reviewed.

Test Plan:
make check

Task ID: #

Blame Rev:

Reviewers: haobo

Reviewed By: haobo

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D12987
2013-09-19 21:48:10 -07:00
Haobo Xu
4734dbb742 [RocksDB] Unit test to show Seek key comparison number
Summary: Added SeekKeyComparison to show the uer key comparison incurred by Seek.

Test Plan:
make perf_context_test
export LEVELDB_TESTS=DBTest.SeekKeyComparison
./perf_context_test --write_buffer_size=500000 --total_keys=10000
./perf_context_test --write_buffer_size=250000 --total_keys=10000

Reviewers: dhruba, xjin

Reviewed By: xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12843
2013-09-18 21:43:41 -07:00
Haobo Xu
72fcbf055d [RocksDB] Fix DBTest.UniversalCompactionSizeAmplification too
Summary: as title

Test Plan: make db_test; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13005
2013-09-17 21:29:33 -07:00
Haobo Xu
5b76338c01 [RocksDB] Fix DBTest.UniversalCompactionTrigger to reflect the correct compaction trigger condition.
Summary: as title

Test Plan: make db_test; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12981
2013-09-17 14:17:48 -07:00
Rajat Goel
11c65021fb Revert "Minor fixes found while trying to compile it using clang on Mac OS X"
This reverts commit 5f2c136c32.
2013-09-15 23:01:26 -07:00
Haobo Xu
1d8c57db23 [RocksDB] Universal compaction trigger condition minor fix
Summary: Currently, when total number of files reaches level0_file_num_compaction_trigger, universal compaction will schedule a compaction job, but the job will not honor the compaction until the total number of files is level0_file_num_compaction_trigger+1. Fixed the condition for consistent behavior (start compaction on reaching level0_file_num_compaction_trigger).

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12945
2013-09-15 22:35:59 -07:00
Rajat Goel
5f2c136c32 Minor fixes found while trying to compile it using clang on Mac OS X 2013-09-15 22:06:14 -07:00
Dhruba Borthakur
4012ca1c7b Added a parameter to limit the maximum space amplification for universal compaction.
Summary:
Added a new field called max_size_amplification_ratio in the
CompactionOptionsUniversal structure. This determines the maximum
percentage overhead of space amplification.

The size amplification is defined to be the ratio between the size of
the oldest file to the sum of the sizes of all other files. If the
size amplification exceeds the specified value, then min_merge_width
and max_merge_width are ignored and a full compaction of all files is done.
A value of 10 means that the size a database that stores 100 bytes
of user data could occupy 110 bytes of physical storage.

Test Plan: Unit test DBTest.UniversalCompactionSpaceAmplification added.

Reviewers: haobo, emayanke, xjin

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12825
2013-09-13 16:27:18 -07:00
Haobo Xu
0e422308aa [RocksDB] Remove Log file immediately after memtable flush
Summary: As title. The DB log file life cycle is tied up with the memtable it backs. Once the memtable is flushed to sst and committed, we should be able to delete the log file, without holding the mutex. This is part of the bigger change to avoid FindObsoleteFiles at runtime. It deals with log files. sst files will be dealt with later.

Test Plan: make check; db_bench

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11709
2013-09-12 11:54:44 -07:00
Haobo Xu
f2f4c8072f [RocksDB] Added nano second stopwatch and new perf counters to track block read cost
Summary: The pupose of this diff is to expose per user-call level precise timing of block read, so that we can answer questions like: a Get() costs me 100ms, is that somehow related to loading blocks from file system, or sth else? We will answer that with EXACTLY how many blocks have been read, how much time was spent on transfering the bytes from os, how much time was spent on checksum verification and how much time was spent on block decompression, just for that one Get. A nano second stopwatch was introduced to track time with higher precision. The cost/precision of the stopwatch is also measured in unit-test. On my dev box, retrieving one time instance costs about 30ns, on average. The deviation of timing results is good enough to track 100ns-1us level events. And the overhead could be safely ignored for 100us level events (10000 instances/s), for example, a viewstate thrift call.

Test Plan: perf_context_test, also testing with viewstate shadow traffic.

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D12351
2013-09-07 21:14:54 -07:00
Dhruba Borthakur
32c965d417 Flush was hanging because the configured options specified that more than 1 memtable need to be merged.
Summary:
There is an config option called Options.min_write_buffer_number_to_merge
that specifies the minimum number of write buffers to merge in memory
before flushing to a file in L0. But in the the case when the db is
being closed, we should not be using this config, instead we should
flush whatever write buffers were available at that time.

Test Plan: Unit test attached.

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12717
2013-09-06 16:28:33 -07:00
Dhruba Borthakur
197034e4c3 An iterator may automatically invoke reseeks.
Summary:
An iterator invokes reseek if the number of sequential skips over the
same userkey exceeds a configured number. This makes iter->Next()
faster (bacause of fewer key compares) if a large number of
adjacent internal keys in a table (sst or memtable) have the
same userkey.

Test Plan: Unit test DBTest.IterReseek.

Reviewers: emayanke, haobo, xjin

Reviewed By: xjin

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11865
2013-09-06 11:50:53 -07:00
Mayank Agarwal
aa5c897d42 Return pathname relative to db dir in LogFile and cleanup AppendSortedWalsOfType
Summary: So that replication can just download from wherever LogFile.Pathname is pointing them.

Test Plan: make all check;./db_repl_stress

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12609
2013-09-04 13:44:43 -07:00
Xing Jin
42c109cc2e New ldb command to convert compaction style
Summary:
Add new command "change_compaction_style" to ldb tool. For
universal->level, it shows "nothing to do". For level->universal, it
compacts all files into a single one and moves the file to level 0.

Also add check for number of files at level 1+ when opening db with
universal compaction style.

Test Plan:
'make all check'. New unit test for internal convertion function. Also manully test various
cmd like:

./ldb change_compaction_style --old_compaction_style=0
--new_compaction_style=1 --db=/tmp/leveldbtest-3088/db_test

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: vamsi, emayanke

Differential Revision: https://reviews.facebook.net/D12603
2013-09-04 13:13:08 -07:00
Mayank Agarwal
c34271a5a5 Fix bug in Counters and record Sequencenumber using only TickerCount
Summary:
The way counters/statistics are implemented in rocksdb demands that enum Tickers and TickerNameMap follow the same order, otherwise statistics exposed from fbcode/rocks get out-of-sync. 2 counters for prefix had violated this order and when I built counters for fbcode/mcrocksdb, statistics for sequence number were appearing out-of-sync.
The other change is to record sequence-number using setTickerCount only and not recordTick. This is because of difference in statistics as understood by rocks/utils which uses ServiceData::statistics function and rocksdb statistics. In rocksdb there is just 1 counter for a countername. But in ServiceData there are 4 independent buckets for every countername-Count, Sum, Average and Rate. SetTickerCount and RecordTick update the same variable in rocksdb but different buckets in ServiceData. Therefore, I had to choose one consistent function from RecordTick or SetTickerCount for sequence number in rocksdb. I chose SetTickerCount because the statistics object in options passed during rocksdb-open is user-dependent and SetTickerCount makes sense there.
There will be a corresponding diff to mcorcksdb in fbcode shortly.

Test Plan: make all check; check ticker value using fprintfs

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12669
2013-09-01 17:59:32 -07:00
Mayank Agarwal
ab5c5c28fe Fix build caused by DeleteFile not tolerating / at the beginning
Summary: db->DeleteFile calls ParseFileName to check name that was returned for sst file. Now, sst filename is returned using TableFileName which uses MakeFileName. This puts a / at the front of the name and ParseFileName doesn't like that. Changed ParseFileName to tolerate /s at the beginning. The test delet_file_test used to pass earlier because this behaviour of MakeFileName had been changed a while back to not return a / during which delete_file_test was checked in. But MakeFileName had to be reverted to add / at the front because GetLiveFiles used at many places outside rocksdb used the previous behaviour of MakeFileName.

Test Plan: make;./delete_filetest;make all check

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12663
2013-09-01 17:59:13 -07:00
Mayank Agarwal
46dcf51ca5 Return a '/' before names of all files through MakeFileName
Summary: // won't hurt but a missing / hurts sometimes

Test Plan: make all check; ./db_repl_stress

Reviewers: vamsi

Reviewed By: vamsi

CC: dhruba

Differential Revision: https://reviews.facebook.net/D12621
2013-08-30 14:25:22 -07:00
Dhruba Borthakur
59de2dbad7 Cleanup DeleteFile API
Summary:
The DeleteFile API was removing files inside the db-lock. This
is now changed to remove files outside the db-lock.
The GetLiveFilesMetadata() returns the smallest and largest
seqnuence number of each file as well.

Test Plan: deletefile_test

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Maniphest Tasks: T63

Differential Revision: https://reviews.facebook.net/D12567
2013-08-28 21:18:58 -07:00
Haobo Xu
48e5ea0c34 [RocksDB] Fix TransformRepFactory related valgrind problem
Summary: Let TransformRepFactory own the passed in transform. Also make it better encapsulated.

Test Plan: make valgrind_check;

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12591
2013-08-28 19:27:54 -07:00
Dhruba Borthakur
fc0c399d2e Introduced a new flag non_blocking_io in ReadOptions.
Summary:
If ReadOptions.non_blocking_io is set to true, then KeyMayExists
and Iterators will return data that is cached in RAM.
If the Iterator needs to do IO from storage to serve the data,
then the Iterator.status() will return Status::IsRetry().

Test Plan:
Enhanced unit test DBTest.KeyMayExist to detect if there were are IOs
issues from storage. Added DBTest.NonBlockingIteration to verify
nonblocking Iterations.

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Maniphest Tasks: T63

Differential Revision: https://reviews.facebook.net/D12531
2013-08-28 10:49:14 -07:00
Haobo Xu
43eef52001 [RocksDB] move stats counting outside of mutex protected region for DB::Get()
Summary:
As title. This is possible as tickers are atomic now.
db_bench on high qps in-memory muti-thread random get workload, showed ~5% throughput improvement.

Test Plan: make check; db_bench; db_stress

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12555
2013-08-27 13:36:10 -07:00
Mayank Agarwal
dad2731729 Fix bug in KeyMayExist
Summary: In KeyMayExist.db_test we do a Flush which causes sst file to be written and added as open file in TableCache, but block cache for the file is not populated. So value_found should have been false where it was true and KeyMayExist.db_test should not have passed earlier. But it passed because BlockReader in table/table.cc takes 2 default arguments at the end called for_compaction and no_io. Although I passed no_io=true from InternalGet to BlockReader, but it understood for_compaction=true and defaulted no_io to false. This is a bug and although will be removed by Dhruba's new patch to incorporate no_io in readoptions, I'm submitting this patch to fix this bug independently of that patch.

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12537
2013-08-26 08:45:58 -07:00
Mayank Agarwal
b1074ac24f Use initializer list for VersionSet
Summary: initialiszer list is fasteri/preferable because it can straightaway call the constructor for this object, otherwise it will be created first and then again initialized. Although gain may not be much in this case because files_ is just a pointer and not a complex object, this is recommended practice.

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12519
2013-08-24 18:16:01 -07:00
Deon Nicholas
573844807c Fix for no_io
Summary: Oops. My bad.

Test Plan: Make all check

Reviewers: emayanke

Reviewed By: emayanke

CC: haobo, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D12525
2013-08-23 16:36:01 -07:00
Tyler Harter
4504c99030 Internal/user key bug fix.
Summary: Fix code so that the filter_block layer only assumes keys are internal when prefix_extractor is set.

Test Plan: ./filter_block_test

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12501
2013-08-23 14:49:57 -07:00
Dhruba Borthakur
1186192ed1 Replace include/leveldb with include/rocksdb.
Summary: Replace include/leveldb with include/rocksdb.

Test Plan:
make clean; make check
make clean; make release

Differential Revision: https://reviews.facebook.net/D12489
2013-08-23 10:51:00 -07:00
Jim Paton
74781a0c49 Add three new MemTableRep's
Summary:
This patch adds three new MemTableRep's: UnsortedRep, PrefixHashRep, and VectorRep.

UnsortedRep stores keys in an std::unordered_map of std::sets. When an iterator is requested, it dumps the keys into an std::set and iterates over that.

VectorRep stores keys in an std::vector. When an iterator is requested, it creates a copy of the vector and sorts it using std::sort. The iterator accesses that new vector.

PrefixHashRep stores keys in an unordered_map mapping prefixes to ordered sets.

I also added one API change. I added a function MemTableRep::MarkImmutable. This function is called when the rep is added to the immutable list. It doesn't do anything yet, but it seems like that could be useful. In particular, for the vectorrep, it means we could elide the extra copy and just sort in place. The only reason I haven't done that yet is because the use of the ArenaAllocator complicates things (I can elaborate on this if needed).

Test Plan:
make -j32 check
./db_stress --memtablerep=vector
./db_stress --memtablerep=unsorted
./db_stress --memtablerep=prefixhash --prefix_size=10

Reviewers: dhruba, haobo, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12117
2013-08-22 23:10:02 -07:00
Xing Jin
17dc128048 Pull from https://reviews.facebook.net/D10917
Summary: Pull Mark's patch and slightly revise it. I revised another place in db_impl.cc with similar new formula.

Test Plan:
make all check. Also run "time ./db_bench --num=2500000000 --numdistinct=2200000000". It has run for 20+ hours and hasn't finished. Looks good so far:

Installed stack trace handler for SIGILL SIGSEGV SIGBUS SIGABRT
LevelDB:    version 2.0
Date:       Tue Aug 20 23:11:55 2013
CPU:        32 * Intel(R) Xeon(R) CPU E5-2660 0 @ 2.20GHz
CPUCache:   20480 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    2500000000
RawSize:    276565.6 MB (estimated)
FileSize:   157356.3 MB (estimated)
Write rate limit: 0
Compression: snappy
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
DB path: [/tmp/leveldbtest-3088/dbbench]
fillseq      :    7202.000 micros/op 138 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
fillsync     :    7148.000 micros/op 139 ops/sec; (2500000 ops)
DB path: [/tmp/leveldbtest-3088/dbbench]
fillrandom   :    7105.000 micros/op 140 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
overwrite    :    6930.000 micros/op 144 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readrandom   :       1.020 micros/op 980507 ops/sec; (0 of 2500000000 found)
DB path: [/tmp/leveldbtest-3088/dbbench]
readrandom   :       1.021 micros/op 979620 ops/sec; (0 of 2500000000 found)
DB path: [/tmp/leveldbtest-3088/dbbench]
readseq      :     113.000 micros/op 8849 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readreverse  :     102.000 micros/op 9803 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
Created bg thread 0x7f0ac17f7700
compact      :  111701.000 micros/op 8 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readrandom   :       1.020 micros/op 980376 ops/sec; (0 of 2500000000 found)
DB path: [/tmp/leveldbtest-3088/dbbench]
readseq      :     120.000 micros/op 8333 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
readreverse  :      29.000 micros/op 34482 ops/sec;
DB path: [/tmp/leveldbtest-3088/dbbench]
... finished 618100000 ops

Reviewers: MarkCallaghan, haobo, dhruba, chip

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D12441
2013-08-22 22:37:13 -07:00
Tyler Harter
94cf218720 Revert "Prefix scan: db_bench and bug fixes"
This reverts commit c2bd8f4824.
2013-08-22 18:01:11 -07:00
Tyler Harter
c2bd8f4824 Prefix scan: db_bench and bug fixes
Summary: If use_prefix_filters is set and read_range>1, then the random seeks will set a the prefix filter to be the prefix of the key which was randomly selected as the target.  Still need to add statistics (perhaps in a separate diff).

Test Plan: ./db_bench --benchmarks=fillseq,prefixscanrandom --num=10000000 --statistics=1 --use_prefix_blooms=1 --use_prefix_api=1 --bloom_bits=10

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, haobo

Differential Revision: https://reviews.facebook.net/D12273
2013-08-22 16:06:50 -07:00
Simha Venkataramaiah
60bf2b7d4a Add APIs to query SST file metadata and to delete specific SST files
Summary: An api to query the level, key ranges, size etc for each SST file and an api to delete a specific file from the db and all associated state in the bookkeeping datastructures.

Notes: Editing the manifest version does not release the obsolete files right away. However deleting the file directly will mess up the iterator. We may need a more aggressive/timely file deletion api.

I have used std::unique_ptr - will switch to boost:: since this is external. thoughts?

Unit test is fragile right now as it expects the compaction at certain levels.

Test Plan: unittest

Reviewers: dhruba, vamsi, emayanke

CC: zshao, leveldb, haobo

Task ID: #

Blame Rev:
2013-08-22 15:27:19 -07:00
Jim Paton
cb703c9d03 Allow WriteBatch::Handler to abort iteration
Summary:
Sometimes you don't need to iterate through the whole WriteBatch. This diff makes the Handler member functions return a bool that indicates whether to abort or not. If they return true, the iteration stops.

One thing I just thought of is that this will break backwards-compability. Maybe it would be better to add a virtual member function WriteBatch::Handler::ShouldAbort() that returns false by default. Comments requested.

I still have to add a new unit test for the abort code, but let's finalize the API first.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, vamsi, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12339
2013-08-21 18:27:48 -07:00
Haobo Xu
f9e2decf7c [RocksDB] Minor iterator cleanup
Summary: Was going through the iterator related code, did some cleanup along the way. Basically replaced array with vector and adopted range based loop where applicable.

Test Plan: make check; make valgrind_check

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12435
2013-08-21 16:54:48 -07:00
Deon Nicholas
b87dcae1a3 Made merge_oprator a shared_ptr; and added TTL unit tests
Test Plan:
- make all check;
- make release;
- make stringappend_test; ./stringappend_test

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb, kailiu

Differential Revision: https://reviews.facebook.net/D12381
2013-08-20 13:35:28 -07:00
Mayank Agarwal
8a3547d38e API for getting archived log files
Summary: Also expanded class LogFile to have startSequene and FileSize and exposed it publicly

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12087
2013-08-19 13:37:04 -07:00
Deon Nicholas
e1346968d8 Merge operator fixes part 1.
Summary:
-Added null checks and revisions to DBIter::MergeValuesNewToOld()
-Added DBIter test to stringappend_test
-Major fix with Merge and TTL
More plans for fixes later.

Test Plan:
-make clean; make stringappend_test -j 32; ./stringappend_test
-make all check;

Reviewers: haobo, emayanke, vamsi, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12315
2013-08-19 11:42:47 -07:00
Mayank Agarwal
387ac0f1e1 Expose statistic for sequence number and implement setTickerCount
Summary: statistic for sequence number is needed by wormhole. setTickerCount is demanded for this statistic. I can't simply recordTick(max_sequence) when db recovers because the statistic iobject is owned by client and may/may not be reset during reopen. Eg. statistic is reset in mcrocksdb whereas it is not in db_stress. Therefore it is best to go with setTickerCount

Test Plan: ./db_stress ... --statistics=1 and observed expected sequence number

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12327
2013-08-15 23:00:20 -07:00
Deon Nicholas
d1d3d15eb7 Tiny fix to db_bench for make release.
Summary:
In release, "found variable assigned but not used anywhere". Changed it to work with
assert. Someone accept this :).

Test Plan: make release -j 32

Reviewers: haobo, dhruba, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12309
2013-08-15 17:50:12 -07:00
Deon Nicholas
ad48c3c262 Benchmarking for Merge Operator
Summary:
Updated db_bench and utilities/merge_operators.h to allow for dynamic benchmarking
of merge operators in db_bench. Added a new test (--benchmarks=mergerandom), which performs
a bunch of random Merge() operations over random keys. Also added a "--merge_operator=" flag
so that the tester can easily benchmark different merge operators. Currently supports
the PutOperator and UInt64Add operator. Support for stringappend or list append may come later.

Test Plan:
	1. make db_bench
	2. Test the PutOperator (simulating Put) as follows:
./db_bench --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom --merge_operator=put
--threads=2

3. Test the UInt64AddOperator (simulating numeric addition) similarly:
./db_bench --value_size=8 --benchmarks=fillrandom,readrandom,updaterandom,readrandom,mergerandom,readrandom
--merge_operator=uint64add --threads=2

Reviewers: haobo, dhruba, zshao, MarkCallaghan

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11535
2013-08-15 17:13:07 -07:00
Xing Jin
0a5afd1afc Minor fix to current codes
Summary:
Minor fix to current codes, including: coding style, output format,
comments. No major logic change. There are only 2 real changes, please see my inline comments.

Test Plan: make all check

Reviewers: haobo, dhruba, emayanke

Differential Revision: https://reviews.facebook.net/D12297
2013-08-14 23:03:57 -07:00
Jim Paton
0307c5fe3a Implement log blobs
Summary:
This patch adds the ability for the user to add sequences of arbitrary data (blobs) to write batches. These blobs are saved to the log along with everything else in the write batch. You can add multiple blobs per WriteBatch and the ordering of blobs, puts, merges, and deletes are preserved.

Blobs are not saves to SST files. RocksDB ignores blobs in every way except for writing them to the log.

Before committing this patch, I need to add some test code. But I'm submitting it now so people can comment on the API.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12195
2013-08-14 16:32:46 -07:00
Haobo Xu
d9dd2a1926 [RocksDB] Expose thread local perf counter for low overhead, per call level performance statistics.
Summary:
As title. No locking/atomic is needed due to thread local. There is also no need to modify the existing client interface, in order to expose related counters.

perf_context_test shows a simple example of retrieving the number of user key comparison done for each put and get call. More counters could be added later.

Sample output
./perf_context_test 1000000
==== Test PerfContextTest.KeyComparisonCount
Inserting 1000000 key/value pairs
...
total user key comparison get: 43446523
total user key comparison put: 8017877
max user key comparison get: 88939
avg user key comparison get:43

Basically, the current skiplist does well on average, but could perform poorly in extreme cases.

Test Plan: run perf_context_test <total number of entries to put/get>

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D12225
2013-08-14 15:24:06 -07:00
Mayank Agarwal
f1bf169484 Counter for merge failure
Summary:
With Merge returning bool, it can keep failing silently(eg. While faling to fetch timestamp in TTL). We need to detect this through a rocksdb counter which can get bumped whenever Merge returns false. This will also be super-useful for the mcrocksdb-counter service where Merge may fail.
Added a counter NUMBER_MERGE_FAILURES and appropriately updated db/merge_helper.cc

I felt that it would be better to directly add counter-bumping in Merge as a default function of MergeOperator class but user should not be aware of this, so this approach seems better to me.

Test Plan: make all check

Reviewers: dnicholas, haobo, dhruba, vamsi

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12129
2013-08-13 14:25:42 -07:00
Tyler Harter
f5f1842282 Prefix filters for scans (v4)
Summary: Similar to v2 (db and table code understands prefixes), but use ReadOptions as in v3.  Also, make the CreateFilter code faster and cleaner.

Test Plan: make db_test; export LEVELDB_TESTS=PrefixScan; ./db_test

Reviewers: dhruba

Reviewed By: dhruba

CC: haobo, emayanke

Differential Revision: https://reviews.facebook.net/D12027
2013-08-13 14:04:56 -07:00
sumeet
3b81df34bd Separate compaction filter for each compaction
Summary:
If we have same compaction filter for each compaction,
application cannot know about the different compaction processes.
Later on, we can put in more details in compaction filter for the
application to consume and use it according to its needs. For e.g. In
the universal compaction, we have a compaction process involving all the
files while others don't involve all the files. Applications may want to
collect some stats only when during full compaction.

Test Plan: run existing unit tests

Reviewers: haobo, dhruba

Reviewed By: dhruba

CC: xinyaohu, leveldb

Differential Revision: https://reviews.facebook.net/D12057
2013-08-13 10:56:20 -07:00
Dhruba Borthakur
03bd4461ad Merge branch 'performance' of github.com:facebook/rocksdb into performance 2013-08-12 10:31:21 -07:00
Dhruba Borthakur
f3967a5132 Merge remote-tracking branch 'origin' into performance 2013-08-12 09:58:50 -07:00
Dhruba Borthakur
93d77a27d2 Universal Compaction should keep DeleteMarkers unless it is the earliest file.
Summary:
The pre-existing code was purging a DeleteMarker if thay key did not
exist in deeper levels.  But in the Universal Compaction Style, all
files are in Level0. For compaction runs that did not include the
earliest file, we were erroneously purging the DeleteMarkers.

The fix is to purge DeleteMarkers only if the compaction includes
the earlist file.

Test Plan: DBTest.Randomized triggers this code path.

Differential Revision: https://reviews.facebook.net/D12081
2013-08-09 14:03:57 -07:00
Xing Jin
8ae905ed63 Fix unit tests for universal compaction (step 2)
Summary:
Continue fixing existing unit tests for universal compaction. I have
tried to apply universal compaction to all unit tests those haven't
called ChangeOptions(). I left a few which are either apparently not
applicable to universal compaction (because they check files/keys/values
at level 1 or above levels), or apparently not related to compaction
(e.g., open a file, open a db).

I also add a new unit test for universal compaction.

Good news is I didn't see any bugs during this round.

Test Plan: Ran "make all check" yesterday. Has rebased and is rerunning

Reviewers: haobo, dhruba

Differential Revision: https://reviews.facebook.net/D12135
2013-08-09 13:35:44 -07:00
Haobo Xu
3a3b1c3e6c [RocksDB] Improve manifest dump to print internal keys in hex for version edits.
Summary: Currently, VersionEdit::DebugString always display internal keys in the original ascii format. This could cause manifest dump to be truncated if internal keys contain special charactors (like null). Also added an option --input_key_hex for ldb idump to indicate that the passed in user keys are in hex.

Test Plan: run ldb manifest_dump

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12111
2013-08-08 16:19:01 -07:00
Xing Jin
17b8f786a3 Fix unit tests/bugs for universal compaction (first step)
Summary:
This is the first step to fix unit tests and bugs for universal
compactiion. I added universal compaction option to ChangeOptions(), and
fixed all unit tests calling ChangeOptions(). Some of these tests
obviously assume more than 1 level and check file number/values in level
1 or above levels. I set kSkipUniversalCompaction for these tests.

The major bug I found is manual compaction with universal compaction never stops. I have put a fix for
it.

I have also set universal compaction as the default compaction and found
at least 20+ unit tests failing. I haven't looked into the details. The
next step is to check all unit tests without calling ChangeOptions().

Test Plan: make all check

Reviewers: dhruba, haobo

Differential Revision: https://reviews.facebook.net/D12051
2013-08-07 14:05:44 -07:00
Dhruba Borthakur
f5fa26b6a9 Merge branch 'performance' of github.com:facebook/rocksdb into performance
Conflicts:
	db/builder.cc
	db/db_impl.cc
	db/version_set.cc
	include/leveldb/statistics.h
2013-08-07 11:58:06 -07:00
Deon Nicholas
68a4cdf3f7 Build fix with merge_test and ttl 2013-08-06 11:42:21 -07:00
Deon Nicholas
c2d7826ced [RocksDB] [MergeOperator] The new Merge Interface! Uses merge sequences.
Summary:
Here are the major changes to the Merge Interface. It has been expanded
to handle cases where the MergeOperator is not associative. It does so by stacking
up merge operations while scanning through the key history (i.e.: during Get() or
Compaction), until a valid Put/Delete/end-of-history is encountered; it then
applies all of the merge operations in the correct sequence starting with the
base/sentinel value.

I have also introduced an "AssociativeMerge" function which allows the user to
take advantage of associative merge operations (such as in the case of counters).
The implementation will always attempt to merge the operations/operands themselves
together when they are encountered, and will resort to the "stacking" method if
and only if the "associative-merge" fails.

This implementation is conjectured to allow MergeOperator to handle the general
case, while still providing the user with the ability to take advantage of certain
efficiencies in their own merge-operator / data-structure.

NOTE: This is a preliminary diff. This must still go through a lot of review,
revision, and testing. Feedback welcome!

Test Plan:
  -This is a preliminary diff. I have only just begun testing/debugging it.
  -I will be testing this with the existing MergeOperator use-cases and unit-tests
(counters, string-append, and redis-lists)
  -I will be "desk-checking" and walking through the code with the help gdb.
  -I will find a way of stress-testing the new interface / implementation using
db_bench, db_test, merge_test, and/or db_stress.
  -I will ensure that my tests cover all cases: Get-Memtable,
Get-Immutable-Memtable, Get-from-Disk, Iterator-Range-Scan, Flush-Memtable-to-L0,
Compaction-L0-L1, Compaction-Ln-L(n+1), Put/Delete found, Put/Delete not-found,
end-of-history, end-of-file, etc.
  -A lot of feedback from the reviewers.

Reviewers: haobo, dhruba, zshao, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11499
2013-08-05 20:14:32 -07:00
Jim Paton
8e792e5896 Add soft_rate_limit stats
Summary: This diff adds histogram stats for soft_rate_limit stalls. It also renames the old rate_limit stats to hard_rate_limit.

Test Plan: make -j32 check

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12021
2013-08-05 18:45:23 -07:00
Mayank Agarwal
1d7b4765c3 Expose base db object from ttl wrapper
Summary: rocksdb replicaiton will need this when writing value+TS from master to slave 'as is'

Test Plan: make

Reviewers: dhruba, vamsi, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11919
2013-08-05 18:44:14 -07:00
Jim Paton
1036537c94 Add soft and hard rate limit support
Summary:
This diff adds support for both soft and hard rate limiting. The following changes are included:

1) Options.rate_limit is renamed to Options.hard_rate_limit.
2) Options.rate_limit_delay_milliseconds is renamed to Options.rate_limit_delay_max_milliseconds.
3) Options.soft_rate_limit is added.
4) If the maximum compaction score is > hard_rate_limit and rate_limit_delay_max_milliseconds == 0, then writes are delayed by 1 ms at a time until the max compaction score falls below hard_rate_limit.
5) If the max compaction score is > soft_rate_limit but <= hard_rate_limit, then writes are delayed by 0-1 ms depending on how close we are to hard_rate_limit.
6) Users can disable 4 by setting hard_rate_limit = 0. They can add a limit to the maximum amount of time waited by setting rate_limit_delay_max_milliseconds > 0. Thus, the old behavior can be preserved by setting soft_rate_limit = 0, which is the default.

Test Plan:
make -j32 check
./db_stress

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12003
2013-08-05 15:43:49 -07:00
Dhruba Borthakur
711a30cb30 Merge branch 'master' into performance
Conflicts:
	include/leveldb/options.h
	include/leveldb/statistics.h
	util/options.cc
2013-08-02 10:22:08 -07:00
Mayank Agarwal
c42485f67c Merge operator for ttl
Summary: Implemented a TtlMergeOperator class which inherits from MergeOperator and is TTL aware. It strips out timestamp from existing_value and attaches timestamp to new_value, calling user-provided-Merge in between.

Test Plan: make all check

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11775
2013-08-01 09:27:17 -07:00
Mayank Agarwal
59d0b02f8b Expand KeyMayExist to return the proper value if it can be found in memory and also check block_cache
Summary: Removed KeyMayExistImpl because KeyMayExist demanded Get like semantics now. Removed no_io from memtable and imm because we need the proper value now and shouldn't just stop when we see Merge in memtable. Added checks to block_cache. Updated documentation and unit-test

Test Plan: make all check;db_stress for 1 hour

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11853
2013-08-01 09:07:46 -07:00
Jim Paton
9700677a2b Slow down writes gradually rather than suddenly
Summary:
Currently, when a certain number of level0 files (level0_slowdown_writes_trigger) are present, RocksDB will slow down each write by 1ms. There is a second limit of level0 files at which RocksDB will stop writes altogether (level0_stop_writes_trigger).

This patch enables the user to supply a third parameter specifying the number of files at which Rocks will start slowing down writes (level0_start_slowdown_writes). When this number is reached, Rocks will slow down writes as a quadratic function of level0_slowdown_writes_trigger - num_level0_files.

For some workloads, this improves latency and throughput. I will post some stats momentarily in https://our.intern.facebook.com/intern/tasks/?t=2613384.

Test Plan:
make -j32 check
./db_stress
./db_bench

Reviewers: dhruba, haobo, MarkCallaghan, xjin

Reviewed By: xjin

CC: leveldb, xjin, zshao

Differential Revision: https://reviews.facebook.net/D11859
2013-07-31 16:20:48 -07:00
Xing Jin
0f0a24e298 Make arena block size configurable
Summary:
Add an option for arena block size, default value 4096 bytes. Arena will allocate blocks with such size.

I am not sure about passing parameter to skiplist in the new virtualized framework, though I talked to Jim a bit. So add Jim as reviewer.

Test Plan:
new unit test, I am running db_test.

For passing paramter from configured option to Arena, I tried tests like:

  TEST(DBTest, Arena_Option) {
  std::string dbname = test::TmpDir() + "/db_arena_option_test";
  DestroyDB(dbname, Options());

  DB* db = nullptr;
  Options opts;
  opts.create_if_missing = true;
  opts.arena_block_size = 1000000; // tested 99, 999999
  Status s = DB::Open(opts, dbname, &db);
  db->Put(WriteOptions(), "a", "123");
  }

and printed some debug info. The results look good. Any suggestion for such a unit-test?

Reviewers: haobo, dhruba, emayanke, jpaton

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D11799
2013-07-31 12:42:23 -07:00
Jim Paton
6db52b525a Don't use redundant Env::NowMicros() calls
Summary: After my patch for stall histograms, there are redundant calls to NowMicros() by both the stop watches and DBImpl::MakeRoomForWrites. So I removed the redundant calls such that the information is gotten from the stopwatch.

Test Plan:
make clean
make -j32 check

Reviewers: dhruba, haobo, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11883
2013-07-29 15:46:36 -07:00
Jim Paton
abc90b067c Use specific DB name in merge_test
Summary: Currently, merge_test uses /tmp/testdb for the test database. It should really use something more specific to merge_test. Most of the other tests use test::TmpDir() + "/<test name>db". This patch implements such behavior for merge_test; it makes merge_test use test::TmpDir() + "/merge_testdb"

Test Plan:
make clean
make -j32 merge_test
./merge_test

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11877
2013-07-29 13:26:38 -07:00
Jim Paton
18afff2e63 Add stall counts to statistics
Summary: Previously, statistics are kept on how much time is spent on stalls of different types. This patch adds support for keeping number of stalls of each type. For example, instead of just reporting how many microseconds are spent waiting for memtables to be compacted, it will also report how many times a write stalled for that to occur.

Test Plan:
make -j32 check
./db_stress

# Not really sure what else should be done...

Reviewers: dhruba, MarkCallaghan, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11841
2013-07-29 10:34:23 -07:00
Dhruba Borthakur
a91fdf1b99 The target file size for L0 files was incorrectly set to LLONG_MAX.
Summary:
The target file size should be valid value. Only if UniversalCompactionStyle
is enabled then set max file size to be LLONG_MAX.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-24 14:28:00 -07:00
Dhruba Borthakur
d7ba5bce37 Revert 6fbe4e981a: If disable wal is set, then batch commits are avoided
Summary:
Revert "If disable wal is set, then batch commits are avoided" because
keeping the mutex while inserting into the skiplist means that readers
and writes are all serialized on the mutex.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-24 10:01:13 -07:00
Jim Paton
52d7ecfc78 Virtualize SkipList Interface
Summary: This diff virtualizes the skiplist interface so that users can provide their own implementation of a backing store for MemTables. Eventually, the backing store will be responsible for its own synchronization, allowing users (and us) to experiment with different lockless implementations.

Test Plan:
make clean
make -j32 check
./db_stress

Reviewers: dhruba, emayanke, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11739
2013-07-23 14:42:27 -07:00
Dhruba Borthakur
6fbe4e981a If disable wal is set, then batch commits are avoided.
Summary:
rocksdb uses batch commit to write to transaction log. But if
disable wal is set, then writes to transaction log are anyways
avoided. In this case, there is not much value-add to batch things,
batching can cause unnecessary delays to Puts().
This patch avoids batching when disableWal is set.

Test Plan:
make check.

I am running db_stress now.

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11763
2013-07-23 14:22:57 -07:00
Mayank Agarwal
bf66c10b13 Use KeyMayExist for WriteBatch-Deletes
Summary:
Introduced KeyMayExist checking during writebatch-delete and removed from Outer Delete API because it uses writebatch-delete.
Added code to skip getting Table from disk if not already present in table_cache.
Some renaming of variables.
Introduced KeyMayExistImpl which allows checking since specified sequence number in GetImpl useful to check partially written writebatch.
Changed KeyMayExist to not be pure virtual and provided a default implementation.
Expanded unit-tests in db_test to check appropriately.
Ran db_stress for 1 hour with ./db_stress --max_key=100000 --ops_per_thread=10000000 --delpercent=50 --filter_deletes=1 --statistics=1.

Test Plan: db_stress;make check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb, xjin

Differential Revision: https://reviews.facebook.net/D11745
2013-07-23 13:36:50 -07:00
Haobo Xu
d364eea1fc [RocksDB] Fix FindMinimumEmptyLevelFitting
Summary: as title

Test Plan: make check;

Reviewers: xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11751
2013-07-22 12:31:43 -07:00
Haobo Xu
9ee68871dc [RocksDB] Enable manual compaction to move files back to an appropriate level.
Summary: As title. This diff added an option reduce_level to CompactRange. When set to true, it will try to move the files back to the minimum level sufficient to hold the data set. Note that the default is set to true now, just to excerise it in all existing tests. Will set the default to false before check-in, for backward compatibility.

Test Plan: make check;

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11553
2013-07-19 16:20:36 -07:00
Dhruba Borthakur
4a745a5666 Merge branch 'master' into performance
Conflicts:
	db/version_set.cc
	include/leveldb/options.h
	util/options.cc
2013-07-17 15:05:57 -07:00
Dhruba Borthakur
76a4923307 Make file-sizes and grandparentoverlap to be unsigned to avoid bad comparisions.
Summary:
The maxGrandParentOverlapBytes_ was signed which was causing
an erroneous comparision between signed and unsigned longs.
This, in turn, was causing compaction-created-output-files
to be very small in size.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D11727
2013-07-17 14:26:06 -07:00
Mayank Agarwal
e9b675bd94 Fix memory leak in KeyMayExist test part of db_test
Summary: NewBloomFilterPolicy call requires Delete to be called later on

Test Plan: make; valgrind ./db_test

Reviewers: haobo, dhruba, vamsi

Differential Revision: https://reviews.facebook.net/D11667
2013-07-12 16:58:57 -07:00
Mayank Agarwal
2a986919d6 Make rocksdb-deletes faster using bloom filter
Summary:
Wrote a new function in db_impl.c-CheckKeyMayExist that calls Get but with a new parameter turned on which makes Get return false only if bloom filters can guarantee that key is not in database. Delete calls this function and if the option- deletes_use_filter is turned on and CheckKeyMayExist returns false, the delete will be dropped saving:
1. Put of delete type
2. Space in the db,and
3. Compaction time

Test Plan:
make all check;
will run db_stress and db_bench and enhance unit-test once the basic design gets approved

Reviewers: dhruba, haobo, vamsi

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11607
2013-07-11 12:11:11 -07:00
Xing Jin
8a5341ec7d Newbie code question
Summary:
This diff is more about my question when reading compaction codes,
instead of a normal diff. I don't quite understand the logic here.

Test Plan: I didn't do any test. If this is a bug, I will continue doing some test.

Reviewers: haobo, dhruba, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11661
2013-07-11 09:03:40 -07:00
Dhruba Borthakur
289efe9922 Update statistics only if needed.
Summary:
Update statistics only if needed.

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-09 16:17:00 -07:00
Dhruba Borthakur
7cb8d462d5 Rename PickCompactionHybrid to PickCompactionUniversal.
Summary:
Rename PickCompactionHybrid to PickCompactionUniversal.
Changed a few LOG message from "Hybrid:" to "Universal:".

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-07-09 16:08:54 -07:00
Haobo Xu
a8d5f8dde2 [RocksDB] Remove old readahead options
Summary: As title.

Test Plan: make check; db_bench

Reviewers: dhruba, MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11643
2013-07-09 11:22:33 -07:00
Haobo Xu
9ba82786ce [RocksDB] Provide contiguous sequence number even in case of write failure
Summary: Replication logic would be simplifeid if we can guarantee that write sequence number is always contiguous, even if write failure occurs. Dhruba and I looked at the sequence number generation part of the code. It seems fixable. Note that if WAL was successful and insert into memtable was not, we would be in an unfortunate state. The approach in this diff is : IO error is expected and error status will be returned to client, sequence number will not be advanced; In-mem error is not expected and we panic.

Test Plan: make check; db_stress

Reviewers: dhruba, sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11439
2013-07-08 15:31:09 -07:00
Dhruba Borthakur
116ec527f2 Renamed 'hybrid_compaction' tp be "Universal Compaction'.
Summary:
All the universal compaction parameters are encapsulated in
a new file universal_compaction.h

Test Plan:
make check
2013-07-03 15:47:53 -07:00
Dhruba Borthakur
47c4191fe8 Reduce write amplification by merging files in L0 back into L0
Summary:
There is a new option called hybrid_mode which, when switched on,
causes HBase style compactions.  Files from L0 are
compacted back into L0. This meat of this compaction algorithm
is in PickCompactionHybrid().

All files reside in L0. That means all files have overlapping
keys. Each file has a time-bound, i.e. each file contains a
range of keys that were inserted around the same time. The
start-seqno and the end-seqno refers to the timeframe when
these keys were inserted.  Files that have contiguous seqno
are compacted together into a larger file. All files are
ordered from most recent to the oldest.

The current compaction algorithm starts to look for
candidate files starting from the most recent file. It continues to
add more files to the same compaction run as long as the
sum of the files chosen till now is smaller than the next
candidate file size. This logic needs to be debated
and validated.

The above logic should reduce write amplification to a
large extent... will publish numbers shortly.

Test Plan: dbstress runs for 6 hours with no data corruption (tested so far).

Differential Revision: https://reviews.facebook.net/D11289
2013-06-30 20:07:04 -07:00
Haobo Xu
71e0f695c1 [RocksDB] Expose count for WriteBatch
Summary: As title. Exposed a Count function that returns the number of updates in a batch. Could be handy for replication sequence number check.

Test Plan: make check;

Reviewers: emayanke, sheki, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11523
2013-06-26 15:13:21 -07:00
Abhishek Kona
5ef6bb8c37 [rocksdb][refactor] statistic printing code to one place
Summary: $title

Test Plan: db_bench --statistics=1

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11373
2013-06-18 20:28:41 -07:00
Haobo Xu
3cc1af2062 [RocksDB] Option for incremental sync
Summary: This diff added an option to control the incremenal sync frequency. db_bench has a new flag bytes_per_sync for easy tuning exercise.

Test Plan: make check; db_bench

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11295
2013-06-18 15:00:32 -07:00
Abhishek Kona
79f4fd2b62 [Rocksdb] Simplify Printing code in db_bench
Summary:
simplify the printing code in db_bench
         use TickersMap and HistogramsNameMap introduced in previous diffs.

Test Plan: ./db_bench --statistics=1 and see if all the statistics are printed

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11355
2013-06-18 14:58:00 -07:00
Dhruba Borthakur
6acbe0fc45 Compact multiple memtables before flushing to storage.
Summary:
Merge multiple multiple memtables in memory before writing it
out to a file in L0.

There is a new config parameter min_write_buffer_number_to_merge
that specifies the number of write buffers that should be merged
together to a single file in storage. The system will not flush
wrte buffers to storage unless at least these many buffers have
accumulated in memory.
The default value of this new parameter is 1, which means that
a write buffer will be immediately flushed to disk as soon it is
ready.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D11241
2013-06-18 14:28:04 -07:00
Abhishek Kona
00124683de [rocksdb] do not trim range for level0 in manual compaction
Summary:
https://code.google.com/p/leveldb/issues/detail?can=1&q=178&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary&id=178

Ported the solution as is to RocksDB.

Test Plan: moved the unit test as manual_compaction_test

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11331
2013-06-17 13:58:17 -07:00
Abhishek Kona
bff718d81c [Rocksdb] Implement filluniquerandom
Summary:
Use a bit set to keep track of which random number is generated.
        Currently only supports single-threaded. All our perf tests are run with threads=1
        Copied over bitset implementation from common/datastructures

Test Plan: printed the generated keys, and verified all keys were present.

Reviewers: MarkCallaghan, haobo, dhruba

Reviewed By: MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11247
2013-06-14 16:17:56 -07:00
Deon Nicholas
2a52e1dcb6 Fix db_bench for release build.
Test Plan: make release

Reviewers: haobo, dhruba, jpaton

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11307
2013-06-14 16:00:47 -07:00
Haobo Xu
1afdf28701 [RocksDB] Compaction Filter Cleanup
Summary: This hopefully gives the right semantics to compaction filter. Will write a small wiki to explain the ideas.

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11121
2013-06-14 14:23:08 -07:00
Abhishek Kona
7a5f71d19a [Rocksdb] measure table open io in a histogram
Summary: Table is setup for compaction using Table::SetupForCompaction. So read block calls can be differentiated b/w Gets/Compaction. Use this and measure times.

Test Plan: db_bench --statistics=1

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D11217
2013-06-13 17:25:09 -07:00
Deon Nicholas
4985a9f73b [Rocksdb] [Multiget] Introduced multiget into db_bench
Summary:
Preliminary! Introduced the --use_multiget=1 and --keys_per_multiget=n
flags for db_bench. Also updated and tested the ReadRandom() method
to include an option to use multiget. By default,
keys_per_multiget=100.

Preliminary tests imply that multiget is at least 1.25x faster per
key than regular get.

Will continue adding Multiget for ReadMissing, ReadHot,
RandomWithVerify, ReadRandomWriteRandom; soon. Will also think
about ways to better verify benchmarks.

Test Plan:
1. make db_bench
2. ./db_bench --benchmarks=fillrandom
3. ./db_bench --benchmarks=readrandom --use_existing_db=1
	      --use_multiget=1 --threads=4 --keys_per_multiget=100
4. ./db_bench --benchmarks=readrandom --use_existing_db=1
	      --threads=4
5. Verify ops/sec (and 1000000 of 1000000 keys found)

Reviewers: haobo, MarkCallaghan, dhruba

Reviewed By: MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11127
2013-06-12 12:42:21 -07:00
Haobo Xu
bdf1085944 [RocksDB] cleanup EnvOptions
Summary:
This diff simplifies EnvOptions by treating it as POD, similar to Options.
- virtual functions are removed and member fields are accessed directly.
- StorageOptions is removed.
- Options.allow_readahead and Options.allow_readahead_compactions are deprecated.
- Unused global variables are removed: useOsBuffer, useFsReadAhead, useMmapRead, useMmapWrite

Test Plan: make check; db_stress

Reviewers: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11175
2013-06-12 11:17:19 -07:00
Dhruba Borthakur
e673d5d26d Do not submit multiple simultaneous seek-compaction requests.
Summary:
The code was such that if multi-threaded-compactions as well
as seek compaction are enabled then it submits multiple
compaction request for the same range of keys. This causes
extraneous sst-files to accumulate at various levels.

Test Plan:
I am not able to write a very good unit test for this one
but can easily reproduce this bug with 'dbstress' with the
following options.

batch=1;maxk=100000000;ops=100000000;ro=0;fm=2;bpl=10485760;of=500000; wbn=3; mbc=20; mb=2097152; wbs=4194304; dds=1; sync=0;  t=32; bs=16384; cs=1048576; of=500000; ./db_stress --disable_seek_compaction=0 --mmap_read=0 --threads=$t --block_size=$bs --cache_size=$cs --open_files=$of --verify_checksum=1 --db=/data/mysql/leveldb/dbstress.dir --sync=$sync --disable_wal=1 --disable_data_sync=$dds --write_buffer_size=$wbs --target_file_size_base=$mb --target_file_size_multiplier=$fm --max_write_buffer_number=$wbn --max_background_compactions=$mbc --max_bytes_for_level_base=$bpl --reopen=$ro --ops_per_thread=$ops --max_key=$maxk --test_batches_snapshots=$batch

Reviewers: leveldb, emayanke

Reviewed By: emayanke

Differential Revision: https://reviews.facebook.net/D11055
2013-06-10 15:49:19 -07:00
Dhruba Borthakur
1b69f1e584 Fix refering freed memory in earlier commit.
Summary: Fix refering freed memory in earlier commit by https://reviews.facebook.net/D11181

Test Plan: make check

Reviewers: haobo, sheki

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11193
2013-06-10 15:08:13 -07:00
Dhruba Borthakur
c5de1b9391 Print name of user comparator in LOG.
Summary:
The current code prints the name of the InternalKeyComparator
in the log file. We would also like to print the name of the
user-specified comparator for easier debugging.

Test Plan: make check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11181
2013-06-10 12:11:55 -07:00
Mayank Agarwal
184343a061 Max_mem_compaction_level can have maximum value of num_levels-1
Summary:
Without this files could be written out to a level greater than the maximum level possible and is the source of the segfaults that wormhole awas getting. The sequence of steps that was followed:
1. WriteLevel0Table was called when memtable was to be flushed for a file.
2. PickLevelForMemTableOutput was called to determine the level to which this file should be pushed.
3. PickLevelForMemTableOutput returned a wrong result because max_mem_compaction_level was equal to 2 even when num_levels was equal to 0.
The fix to re-initialize max_mem_compaction_level based on num_levels passed seems correct.

Test Plan: make all check; Also made a dummy file to mimic the wormhole-file behaviour which was causing the segfaults and found that the same segfault occurs without this change and not with this.

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11157
2013-06-09 10:38:55 -07:00
Abhishek Kona
e982b5a489 [Rocksdb] measure table open io in a histogram
Summary: as title

Test Plan: db_bench --statistics=1 check for statistic.

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11109
2013-06-07 10:02:28 -07:00
Deon Nicholas
db1f0cddf3 Fixed valgrind errors 2013-06-05 17:25:16 -07:00
Deon Nicholas
d8c7c45ea0 Very basic Multiget and simple test cases.
Summary:
Implemented the MultiGet operator which takes in a list of keys
and returns their associated values. Currently uses std::vector as its
container data structure. Otherwise, it works identically to "Get".

Test Plan:
 1. make db_test      ; compile it
 2. ./db_test         ; test it
 3. make all check    ; regress / run all tests
 4. make release      ; (optional) compile with release settings

Reviewers: haobo, MarkCallaghan, dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10875
2013-06-05 11:22:38 -07:00
Abhishek Kona
d91b42ee27 [Rocksdb] Measure all FSYNC/SYNC times
Summary: Add stop watches around all sync calls.

Test Plan: db_bench check if respective histograms are printed

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11073
2013-06-05 11:06:21 -07:00
Abhishek Kona
ee522d0032 [Rocksdb] Log on disable/enable file deletions
Summary: as title

Test Plan: compile

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11085
2013-06-05 10:48:24 -07:00
Mark Callaghan
d9f538e1a9 Improve output for GetProperty('leveldb.stats')
Summary:
Display separate values for read, write & total compaction IO.
Display compaction amplification and write amplification.
Add similar values for the period since the last call to GetProperty. Results since the server started
are reported as "cumulative" stats. Results since the last call to GetProperty are reported as
"interval" stats.

Level  Files Size(MB) Time(sec)  Read(MB) Write(MB)    Rn(MB)  Rnp1(MB)  Wnew(MB) Amplify Read(MB/s) Write(MB/s)      Rn     Rnp1     Wnp1     NewW    Count  Ln-stall
----------------------------------------------------------------------------------------------------------------------------------------------------------------------
  0        7       13        21         0       211         0         0       211     0.0       0.0        10.1        0        0        0        0      113       0.0
  1       79      157        88       993       989       198       795       194     9.0      11.3        11.2      106      405      502       97       14       0.0
  2       19       36         5        63        63        37        27        36     2.4      12.3        12.2       19       14       32       18       12       0.0
>>>>>>>>>>>>>>>>>>>>>>>>> text below has been is new and/or reformatted
Uptime(secs): 122.2 total, 0.9 interval
Compaction IO cumulative (GB): 0.21 new, 1.03 read, 1.23 write, 2.26 read+write
Compaction IO cumulative (MB/sec): 1.7 new, 8.6 read, 10.3 write, 19.0 read+write
Amplification cumulative: 6.0 write, 11.0 compaction
Compaction IO interval (MB): 5.59 new, 0.00 read, 5.59 write, 5.59 read+write
Compaction IO interval (MB/sec): 6.5 new, 0.0 read, 6.5 write, 6.5 read+write
Amplification interval: 1.0 write, 1.0 compaction
>>>>>>>>>>>>>>>>>>>>>>>> text above is new and/or reformatted
Stalls(secs): 90.574 level0_slowdown, 0.000 level0_numfiles, 10.165 memtable_compaction, 0.000 leveln_slowdown

Task ID: #

Blame Rev:

Test Plan:
make check, run db_bench

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/D11049
2013-06-03 20:24:49 -07:00
Haobo Xu
2b1fb5b01d [RocksDB] Add score column to leveldb.stats
Summary: Added the 'score' column to the compaction stats output, which shows the level total size devided by level target size. Could be useful when monitoring compaction decisions...

Test Plan: make check; db_bench

Reviewers: dhruba

CC: leveldb, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D11025
2013-06-03 17:38:27 -07:00
Haobo Xu
d897d33bf1 [RocksDB] Introduce Fast Mutex option
Summary:
This diff adds an option to specify whether PTHREAD_MUTEX_ADAPTIVE_NP will be enabled for the rocksdb single big kernel lock. db_bench also have this option now.
Quickly tested 8 thread cpu bound 100 byte random read.
No fast mutex: ~750k/s ops
With fast mutex: ~880k/s ops

Test Plan: make check; db_bench; db_stress

Reviewers: dhruba

CC: MarkCallaghan, leveldb

Differential Revision: https://reviews.facebook.net/D11031
2013-06-01 23:11:34 -07:00
Haobo Xu
ab8d2f6ab2 [RocksDB] [Performance] Allow different posix advice to be applied to the same table file
Summary:
Current posix advice implementation ties up the access pattern hint with the creation of a file.
It is not possible to apply different advice for different access (random get vs compaction read),
without keeping two open files for the same table. This patch extended the RandomeAccessFile interface
to accept new access hint at anytime. Particularly, we are able to set different access hint on the same
table file based on when/how the file is used.
Two options are added to set the access hint, after the file is first opened and after the file is being
compacted.

Test Plan: make check; db_stress; db_bench

Reviewers: dhruba

Reviewed By: dhruba

CC: MarkCallaghan, leveldb

Differential Revision: https://reviews.facebook.net/D10905
2013-05-30 19:08:44 -07:00
Haobo Xu
2df65c118c [RocksDB] Dump counters and histogram data periodically with compaction stats
Summary: As title

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10995
2013-05-29 12:00:18 -07:00
Dhruba Borthakur
a8d807ee91 Record the number of open db iterators.
Summary: Enhance the statitics to report the number of open db iterators.

Test Plan: make check

Reviewers: haobo, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10983
2013-05-29 08:47:08 -07:00
Haobo Xu
fb684da082 [RocksDB] Fix CorruptionTest
Summary: Overriding block_size_deviation to zero, so that CorruptionTest can pass.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D10977
2013-05-28 12:36:42 -07:00
heyongqiang
4b29651206 add block deviation option to terminate a block before it exceeds block_size
Summary: a new option block_size_deviation is added.

Test Plan: run db_test and db_bench

Reviewers: dhruba, haobo

Reviewed By: haobo

Differential Revision: https://reviews.facebook.net/D10821
2013-05-24 15:52:49 -07:00
Haobo Xu
ef15b9d178 [RocksDB] Fix MaybeDumpStats
Summary: MaybeDumpStats was causing lock problem

Test Plan: make check; db_stress

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D10935
2013-05-24 15:43:16 -07:00
Haobo Xu
0e879c93de [RocksDB] dump leveldb.stats periodically in LOG file.
Summary:
Added an option stats_dump_period_sec to dump leveldb.stats to LOG periodically for diagnosis.
By defauly, it's set to a very big number 3600 (1 hour).

Test Plan: make check;

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D10761
2013-05-23 16:56:59 -07:00
Dhruba Borthakur
26541860d3 The max size of the write buffer size can be 64 GB.
Summary: There was an artifical limit on the size of the write buffer size.

Test Plan: make check

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10911
2013-05-23 15:00:27 -07:00
Dhruba Borthakur
898f79372f Fix valgrind errors introduced by https://reviews.facebook.net/D10863
Summary:
The valgrind errors were in the unit tests where we change the
number of levels of a database using internal methods.

Test Plan:
valgrind ./reduce_levels_test
valgrind ./db_test

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10893
2013-05-23 12:14:41 -07:00
Haobo Xu
c2e2460f8a [RocksDB] Expose DBStatistics
Summary: Make Statistics usable by client

Test Plan: make check; db_bench

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D10899
2013-05-23 11:49:38 -07:00
Haobo Xu
87d0af15d8 [RocksDB] Introduce an option to skip log error on recovery
Summary:
Currently, with paranoid_check on, DB::Open will fail on any log read error on recovery.
If client is ok with losing most recent updates, we could simply skip those errors.
However, it's important to introduce an additional flag, so that paranoid_check can
still guard against more serious problems.

Test Plan: make check; db_stress

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb, emayanke

Differential Revision: https://reviews.facebook.net/D10869
2013-05-21 14:30:36 -07:00
Dhruba Borthakur
d1aaaf718c Ability to set different size fanout multipliers for every level.
Summary:
There is an existing field Options.max_bytes_for_level_multiplier that
sets the multiplier for the size of each level in the database.

This patch introduces the ability to set different multipliers
for every level in the database. The size of a level is determined
by using both max_bytes_for_level_multiplier as well as the
per-level fanout.

size of level[i] = size of level[i-1] * max_bytes_for_level_multiplier
                   * fanout[i-1]

The default value of fanout is 1, so that it is backward compatible.

Test Plan: make check

Reviewers: haobo, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10863
2013-05-21 13:50:20 -07:00
Haobo Xu
c3c13db346 [RocksDB] [Performance Bug] MemTable::Get Slow
Summary:
The merge operator diff introduced a performance problem in MemTable::Get.
An exit condition is missed when the current key does not match the user key.
This could lead to full memtable scan if the user key is not found.

Test Plan: make check; db_bench

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10851
2013-05-21 13:40:38 -07:00
Abhishek Kona
e1174306c5 [RocksDB] Simplify StopWatch implementation
Summary:
Make stop watch a simple implementation, instead of subclass of a virtual class
Allocate stop watches off the stack instead of heap.
Code is more terse now.

Test Plan: make all check, db_bench with --statistics=1

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10809
2013-05-17 10:55:34 -07:00
Abhishek Kona
446151cd20 [Rocksdb] Remove unused double apis to record into histograms
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
2013-05-16 10:40:30 -07:00
Haobo Xu
4ca3c67bd3 [RocksDB] Cleanup compaction filter to use a class interface, instead of function pointer and additional context pointer.
Summary:
This diff replaces compaction_filter_args and CompactionFilter with a single compaction_filter parameter. It gives CompactionFilter better encapsulation and a similar look to Comparator and MergeOpertor, which improves consistency of the overall interface.
The change is not backward compatible. Nevertheless, the two references in fbcode are not in production yet.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D10773
2013-05-13 14:06:10 -07:00
Haobo Xu
73c0a33346 [RocksDB] fix compaction filter trigger condition
Summary:
Currently, compaction filter is run on internal key older than the oldest snapshot, which is incorrect.
Compaction filter should really be run on the most recent internal key when there is no external snapshot.

Test Plan: make check; db_stress

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D10641
2013-05-13 12:33:02 -07:00
Abhishek Kona
8d58ecdc29 [RocksDB] Expose compaction stalls via db_statistics
Test Plan: make check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10575
2013-05-10 14:41:45 -07:00
Dhruba Borthakur
a8d3aa2c26 Assertion failure for L0-L1 compactions.
Summary:
For level-0 compactions, we try to find if can include more L0 files
in the same compaction run. This causes the 'smallest' and 'largest'
key to get extended to a larger range. But the suceeding call to
ParentRangeInCompaction() was still using the earlier
values of 'smallest' and 'largest',

Because of this bug, a file in L1 can be part of two concurrent
compactions: one L0-L1 compaction and the other L1-L2 compaction.

This should not cause any data loss, but will cause an assertion
failure with debug builds.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D10677
2013-05-08 17:10:11 -07:00
Abhishek Kona
988c20b9f7 [RocksDB] Clear Archive WAL files
Summary:
WAL files are moved to archive directory and clear only at DB::Open.
Can lead to a lot of space consumption in a Database. Added logic to periodically clear Archive Directory too.

Test Plan: make all check + add unit test

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10617
2013-05-06 11:41:01 -07:00
Haobo Xu
05e8854085 [Rocksdb] Support Merge operation in rocksdb
Summary:
This diff introduces a new Merge operation into rocksdb.
The purpose of this review is mostly getting feedback from the team (everyone please) on the design.

Please focus on the four files under include/leveldb/, as they spell the client visible interface change.
include/leveldb/db.h
include/leveldb/merge_operator.h
include/leveldb/options.h
include/leveldb/write_batch.h

Please go over local/my_test.cc carefully, as it is a concerete use case.

Please also review the impelmentation files to see if the straw man implementation makes sense.

Note that, the diff does pass all make check and truly supports forward iterator over db and a version
of Get that's based on iterator.

Future work:
- Integration with compaction
- A raw Get implementation

I am working on a wiki that explains the design and implementation choices, but coding comes
just naturally and I think it might be a good idea to share the code earlier. The code is
heavily commented.

Test Plan: run all local tests

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb, zshao, sheki, emayanke, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D9651
2013-05-03 16:59:02 -07:00
Abhishek Kona
41cb922b34 Allocate the LogReporter from heap. Summary:
Summary:
The current code has a bug that take address of stack allocated LogReporter.
It is causing SIGSEGV because the stack address is no longer valid when referenced.

Test Plan: Tested on prod.

Reviewers: haobo, dhruba, heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D10557
2013-04-29 13:19:24 -07:00
Abhishek Kona
fb96ec1686 [RocksDB] Print all internally collected histograms in db_bench. Also print p95
Summary: $title

Test Plan: make db_bench . run db_bench and check for expected output

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10521
2013-04-25 13:36:47 -07:00
Haobo Xu
eb6d139666 [RocksDB] Move table.h to table/
Summary:
- don't see a point exposing table.h to the public.
- fixed make clean to remove also *.d files.

Test Plan: make check; db_stress

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10479
2013-04-22 16:07:56 -07:00
Abhishek Kona
344e832f55 [RocksDB] Fix ReadMissing in db_bench
Summary: D8943 Broke read_missing. Fix it by adding a "." at the end of the generated key

Test Plan: generate, print and check the key has a "."

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10455
2013-04-22 15:44:19 -07:00
Haobo Xu
b4243e5a3d [RocksDB] CompactionFilter cleanup
Summary:
- removed the compaction_filter_value from the callback interface. Restrict compaction filter to purging values.
- modify some comments to reflect curent status.

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10335
2013-04-20 10:26:51 -07:00
Mark Callaghan
b1ff9ac9c5 Add --writes_per_second rate limit, print p99.99 in histogram
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
2013-04-20 10:26:51 -07:00
Haobo Xu
1255dcd446 [RocksDB] Add stacktrace signal handler
Summary:
This diff provides the ability to print out a stacktrace when the process receives certain signals.
Currently, we enable this for the following signals (program error related):
SIGILL SIGSEGV SIGBUS SIGABRT
Application simply #include "util/stack_trace.h" and call leveldb::InstallStackTraceHandler() during initialization, if signal handler is needed. It's not done automatically when openning db, because it's the application(process)'s responsibility to install signal handler and some applications might already have their own (like fbcode).

Sample output:
Received signal 11 (Segmentation fault)
#0  0x408ff0 ./signal_test() [0x408ff0] /home/haobo/rocksdb/util/signal_test.cc:4
#1  0x40827d ./signal_test() [0x40827d] /home/haobo/rocksdb/util/signal_test.cc:24
#2  0x7f8bb183172e /usr/local/fbcode/gcc-4.7.1-glibc-2.14.1/lib/libc.so.6(__libc_start_main+0x10e) [0x7f8bb183172e] ??:0
#3  0x408ebc ./signal_test() [0x408ebc] /home/engshare/third-party/src/glibc/glibc-2.14.1/glibc-2.14.1/csu/../sysdeps/x86_64/elf/start.S:113
Segmentation fault (core dumped)

For each frame, we print the raw pointer, the symbol provided by backtrace_symbols (still not good enough), and the source file/line. Note that address translation is done by directly shell out to addr2line. ??:0 means addr2line fails to do the translation. Hacky, but I think it's good for now.

Test Plan: signal_test.cc

Reviewers: dhruba, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10173
2013-04-20 10:26:50 -07:00
Abhishek Kona
7c6c3c0ff4 [Rockdsdb] Better Error messages. Closing db instead of deleting db
Summary: A better error message. A local change. Did not look at other places where this could be done.

Test Plan: compile

Reviewers: dhruba, MarkCallaghan

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10251
2013-04-15 15:27:15 -07:00
Dhruba Borthakur
9b81d3c406 Simplified level_ptrs by using a std:vector
Summary: Simplified level_ptrs by using a std:vector

Test Plan: make check

Reviewers: sheki, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10245
2013-04-15 13:52:51 -07:00
Haobo Xu
013e9ebbf1 [RocksDB] [Performance] Speed up FindObsoleteFiles
Summary:
FindObsoleteFiles was slow, holding the single big lock, resulted in bad p99 behavior.
Didn't profile anything, but several things could be improved:
1. VersionSet::AddLiveFiles works with std::set, which is by itself slow (a tree).
   You also don't know how many dynamic allocations occur just for building up this tree.
   switched to std::vector, also added logic to pre-calculate total size and do just one allocation
2. Don't see why env_->GetChildren() needs to be mutex proteced, moved to PurgeObsoleteFiles where
   mutex could be unlocked.
3. switched std::set to std:unordered_set, the conversion from vector is also inside PurgeObsoleteFiles
I have a feeling this should pretty much fix it.

Test Plan: make check;  db_stress

Reviewers: dhruba, heyongqiang, MarkCallaghan

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D10197
2013-04-12 11:29:27 -07:00
Mayank Agarwal
94d86b25a9 Fix memory leak for probableWALfiles in db_impl.cc
Summary: using unique_ptr to have automatic delete for probableWALfiles in db_impl.cc

Test Plan: make

Reviewers: sheki, dhruba

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10083
2013-04-11 16:57:15 -07:00
Dhruba Borthakur
7730587120 Prevent segfault in OpenCompactionOutputFile
Summary:
The segfault was happening because the program was unable to open a new
sst file (as part of the compaction) because the process ran out of
file descriptors.

The fix is to check the return status of the file creation before taking
any other action.

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fabf03f9700 (LWP 29904)]
leveldb::DBImpl::OpenCompactionOutputFile (this=this@entry=0x7fabf9011400, compact=compact@entry=0x7fabf741a2b0) at db/db_impl.cc:1399
1399    db/db_impl.cc: No such file or directory.
(gdb) where

Test Plan: make check

Reviewers: MarkCallaghan, sheki

Reviewed By: MarkCallaghan

CC: leveldb

Differential Revision: https://reviews.facebook.net/D10101
2013-04-10 09:59:48 -07:00
Abhishek Kona
574b76f710 [RocksDB][Bug] Look at all the files, not just the first file in TransactionLogIter as BatchWrites can leave it in Limbo
Summary:
Transaction Log Iterator did not move to the next file in the series if there was a write batch at the end of the currentFile.
The solution is if the last seq no. of the current file is < RequestedSeqNo. Assume the first seqNo. of the next file has to satisfy the request.

Also major refactoring around the code. Moved opening the logreader to a seperate function, got rid of goto.

Test Plan: added a unit test for it.

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb, emayanke

Differential Revision: https://reviews.facebook.net/D10029
2013-04-08 16:28:09 -07:00
Abhishek Kona
0e40185a7d [Rocksdb] Remove useless struct TableAndFile
Summary:
TableAndFile was a struct used earlier to delete the file as we did not have std::unique_ptr in the codebase.
With Chip introducing C++11 hotness like std::unique_ptr we can do away with the struct.

Test Plan: make all check

Reviewers: haobo, heyongqiang

Reviewed By: heyongqiang

CC: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D9975
2013-04-05 11:26:46 -07:00
Abhishek Kona
ca789a10cc [Rocksdb] Recover last updated sequence number from manifest also.
Summary:
During recovery, last_updated_manifest number was not set if there were no records in the Write-ahead log.
Now check for the recovered manifest also and set last_updated_manifest file to the max value.

Test Plan: unit test

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9891
2013-04-02 17:18:27 -07:00
Haobo Xu
6763110867 [RocksDB] Replace iterator based loop with range based loop for stl containers
Summary:
As title.
Code is shorter and cleaner
See https://our.dev.facebook.com/intern/tasks/?t=2233981

Test Plan: make check

Reviewers: dhruba, heyongqiang

Reviewed By: dhruba

CC: leveldb, zshao

Differential Revision: https://reviews.facebook.net/D9789
2013-04-02 11:46:45 -07:00
Haobo Xu
645ff8f231 Let's get rid of delete as much as possible, here are some examples.
Summary:
If a class owns an object:
 - If the object can be null => use a unique_ptr. no delete
 - If the object can not be null => don't even need new, let alone delete
 - for runtime sized array => use vector, no delete.

Test Plan: make check

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb, zshao, sheki, emayanke, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D9783
2013-03-28 17:31:44 -07:00
Abhishek Kona
3b51605b8d [RocksDB] Fix binary search while finding probable wal files
Summary:
RocksDB does a binary search to look at the files which might contain the requested sequence number at the call GetUpdatesSince.
There was a bug in the binary search => when the file pointed by the middle index of bsearch was empty/corrupt it needst to resize the vector and update indexes.
This now fixes that.

Test Plan: existing unit tests pass.

Reviewers: heyongqiang, dhruba

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9777
2013-03-28 13:37:15 -07:00
Abhishek Kona
8e9c781ae5 [Rocksdb] Fix Crash on finding a db with no log files. Error out instead
Summary:
If the vector returned by GetUpdatesSince is empty, it is still returned to the
user. This causes it throw an std::range error.
The probable file list is checked and it returns an IOError status instead of OK now.

Test Plan: added a unit test.

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9771
2013-03-28 13:19:07 -07:00
Abhishek Kona
7fdd5f5b33 Use non-mmapd files for Write-Ahead Files
Summary:
Use non mmapd files for Write-Ahead log.
Earlier use of MMaped files. made the log iterator read ahead and miss records.
Now the reader and writer will point to the same physical location.

There is no perf regression :
./db_bench --benchmarks=fillseq --db=/dev/shm/mmap_test --num=$(million 20) --use_existing_db=0 --threads=2
with This diff :
fillseq      :      10.756 micros/op 185281 ops/sec;   20.5 MB/s
without this dif :
fillseq      :      11.085 micros/op 179676 ops/sec;   19.9 MB/s

Test Plan: unit test included

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9741
2013-03-28 13:13:35 -07:00
Abhishek Kona
63f216ee0a memory manage statistics
Summary:
Earlier Statistics object was a raw pointer. This meant the user had to clear up
the Statistics object after creating the database. In most use cases the database is created in a function and the statistics pointer is out of scope. Hence the statistics object would never be deleted.
Now Using a shared_ptr to manage this.

Want this in before the next release.

Test Plan: make all check.

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9735
2013-03-27 11:27:39 -07:00
Haobo Xu
ecd8db0200 [RocksDB] Minimize Mutex protected code section in the critical path
Summary: rocksdb uses a single global lock to protect in memory metadata. We should minimize the mutex protected code section to increase the effective parallelism of the program. See https://our.intern.facebook.com/intern/tasks/?t=2218928

Test Plan:
make check
db_bench

Reviewers: dhruba, heyongqiang

CC: zshao, leveldb

Differential Revision: https://reviews.facebook.net/D9705
2013-03-26 22:42:26 -07:00
Abhishek Kona
9b70529c86 Disable Unit Test for TransactionLogIteratorStall
Summary:
The unit test fails as our solution does not work with MMap'd files.
Disable the failing unit test. Put it back with the next diff which should fix the problem.

Test Plan: db_test

Reviewers: heyongqiang

CC: dhruba

Differential Revision: https://reviews.facebook.net/D9645
2013-03-21 15:51:18 -07:00
Abhishek Kona
27c15fb67e TransactionLogIter should stall at the last record. Currently it errors out
Summary:
* Add a method to check if the log reader is at EOF.
* If we know a record has been flushed force the log_reader to believe it is not at EOF, using a new method UnMarkEof().

This does not work with MMpaed files.

Test Plan: added a unit test.

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9567
2013-03-21 15:12:35 -07:00
Dhruba Borthakur
d0798f67f4 Run compactions even if workload is readonly or read-mostly.
Summary:
The events that trigger compaction:
* opening the database
* Get -> only if seek compaction is not disabled and other checks are true
* MakeRoomForWrite -> when memtable is full
* BackgroundCall ->
  If the background thread is about to do a compaction run, it schedules
  a new background task to trigger a possible compaction. This will cause
  additional background threads to find and process other compactions that
  can run concurrently.

Test Plan: ran db_bench with overwrite and readonly alternatively.

Reviewers: sheki, MarkCallaghan

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9579
2013-03-20 23:43:29 -07:00
Dhruba Borthakur
ad96563b79 Ability to configure bufferedio-reads, filesystem-readaheads and mmap-read-write per database.
Summary:
This patch allows an application to specify whether to use bufferedio,
reads-via-mmaps and writes-via-mmaps per database. Earlier, there
was a global static variable that was used to configure this functionality.

The default setting remains the same (and is backward compatible):
 1. use bufferedio
 2. do not use mmaps for reads
 3. use mmap for writes
 4. use readaheads for reads needed for compaction

I also added a parameter to db_bench to be able to explicitly specify
whether to do readaheads for compactions or not.

Test Plan: make check

Reviewers: sheki, heyongqiang, MarkCallaghan

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9429
2013-03-20 23:14:03 -07:00
Mayank Agarwal
b1bea58457 Fix more signed-unsigned comparisons
Summary: Some comparisons left in log_test.cc and db_test.cc complained by make

Test Plan: make

Reviewers: dhruba, sheki

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9537
2013-03-19 17:21:36 -07:00
Mayank Agarwal
487168cdcf Fixed sign-comparison in rocksdb code-base and fixed Makefile
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
2013-03-19 14:35:23 -07:00
Mark Callaghan
72d14eafd3 add --benchmarks=levelstats option to db_bench, prevent "nan" in stats output
Summary:
Add --benchmarks=levelstats option to report per-level stats (#files, #bytes)
Change readwhilewriting test to report response time for writes but exclude
them from the stats merged by all threads.
Prevent "NaN" in stats output by preventing division by 0.
Remove "o" file I committed by mistake.

Task ID: #

Blame Rev:

Test Plan:
make check

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9513
2013-03-19 13:14:44 -07:00
Abhishek Kona
02c459805b Ignore a zero-sized file while looking for a seq-no in GetUpdatesSince
Summary:
Rocksdb can create 0 sized log files when it is opened and closed without any operations.
The GetUpdatesSince fails currently if there is a log file of size zero.

This diff fixes this. If there is a log file is 0, it is removed form the probable_file_list

Test Plan: unit test

Reviewers: dhruba, heyongqiang

Reviewed By: heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9507
2013-03-19 11:00:09 -07:00
Abhishek Kona
7b9db9c98e DO not report level size as zero when there are no files in L0
Summary:
Instead of checking for number of files in L0. Check for number of files in the requested level.

Bug introduced in D4929 (diff trying to do too many things).

Test Plan: db_test.

Reviewers: dhruba, MarkCallaghan

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9483
2013-03-18 12:04:38 -07:00
Mark Callaghan
5a8c8845a9 Enhance db_bench
Summary:
Add --benchmarks=updaterandom for read-modify-write workloads. This is different
from --benchmarks=readrandomwriterandom in a few ways. First, an "operation" is the
combined time to do the read & write rather than treating them as two ops. Second,
the same key is used for the read & write.

Change RandomGenerator to support rows larger than 1M. That was using "assert"
to fail and assert is compiled-away when -DNDEBUG is used.

Add more options to db_bench
--duration - sets the number of seconds for tests to run. When not set the
operation count continues to be the limit. This is used by random operation
tests.

--use_snapshot - when set GetSnapshot() is called prior to each random read.
This is to measure the overhead from using snapshots.

--get_approx - when set GetApproximateSizes() is called prior to each random
read. This is to measure the overhead for a query optimizer.

Task ID: #

Blame Rev:

Test Plan:
run db_bench

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9267
2013-03-14 16:00:23 -07:00
Mayank Agarwal
5b278b53ae Fix valgrind errors in rocksdb tests: auto_roll_logger_test, reduce_levels_test
Summary: Fix for memory leaks in rocksdb tests. Also modified the variable NUM_FAILED_TESTS to print the actual number of failed tests.

Test Plan: make <test>; valgrind --leak-check=full ./<test>

Reviewers: sheki, dhruba

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9333
2013-03-12 16:03:16 -07:00
Dhruba Borthakur
ebf16f57c9 Prevent segfault because SizeUnderCompaction was called without any locks.
Summary:
SizeBeingCompacted was called without any lock protection. This causes
crashes, especially when running db_bench with value_size=128K.
The fix is to compute SizeUnderCompaction while holding the mutex and
passing in these values into the call to Finalize.

(gdb) where
#4  leveldb::VersionSet::SizeBeingCompacted (this=this@entry=0x7f0b490931c0, level=level@entry=4) at db/version_set.cc:1827
#5  0x000000000043a3c8 in leveldb::VersionSet::Finalize (this=this@entry=0x7f0b490931c0, v=v@entry=0x7f0b3b86b480) at db/version_set.cc:1420
#6  0x00000000004418d1 in leveldb::VersionSet::LogAndApply (this=0x7f0b490931c0, edit=0x7f0b3dc8c200, mu=0x7f0b490835b0, new_descriptor_log=<optimized out>) at db/version_set.cc:1016
#7  0x00000000004222b2 in leveldb::DBImpl::InstallCompactionResults (this=this@entry=0x7f0b49083400, compact=compact@entry=0x7f0b2b8330f0) at db/db_impl.cc:1473
#8  0x0000000000426027 in leveldb::DBImpl::DoCompactionWork (this=this@entry=0x7f0b49083400, compact=compact@entry=0x7f0b2b8330f0) at db/db_impl.cc:1757
#9  0x0000000000426690 in leveldb::DBImpl::BackgroundCompaction (this=this@entry=0x7f0b49083400, madeProgress=madeProgress@entry=0x7f0b41bf2d1e, deletion_state=...) at db/db_impl.cc:1268
#10 0x0000000000428f42 in leveldb::DBImpl::BackgroundCall (this=0x7f0b49083400) at db/db_impl.cc:1170
#11 0x000000000045348e in BGThread (this=0x7f0b49023100) at util/env_posix.cc:941
#12 leveldb::(anonymous namespace)::PosixEnv::BGThreadWrapper (arg=0x7f0b49023100) at util/env_posix.cc:874
#13 0x00007f0b4a7cf10d in start_thread (arg=0x7f0b41bf3700) at pthread_create.c:301
#14 0x00007f0b49b4b11d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:115

Test Plan:
make check

I am running db_bench with a value size of 128K to see if the segfault is fixed.

Reviewers: MarkCallaghan, sheki, emayanke

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9279
2013-03-11 14:09:01 -07:00
Dhruba Borthakur
6d812b6afb A mechanism to detect manifest file write errors and put db in readonly mode.
Summary:
If there is an error while writing an edit to the manifest file, the manifest
file is closed and reopened to check if the edit made it in. However, if the
re-opening of the manifest is unsuccessful and options.paranoid_checks is set
t true, then the db refuses to accept new puts, effectively putting the db
in readonly mode.

In a future diff, I would like to make the default value of paranoid_check
to true.

Test Plan: make check

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9201
2013-03-07 09:45:49 -08:00
Abhishek Kona
d68880a1b9 Do not allow Transaction Log Iterator to fall ahead when writer is writing the same file
Summary:
Store the last flushed, seq no. in db_impl. Check against it in
transaction Log iterator. Do not attempt to read ahead if we do not know
if the data is flushed completely.
Does not work if flush is disabled. Any ideas on fixing that?
* Minor change, iter->Next is called the first time automatically for
* the first time.

Test Plan:
existing test pass.
More ideas on testing this?
Planning to run some stress test.

Reviewers: dhruba, heyongqiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9087
2013-03-06 14:05:53 -08:00
Dhruba Borthakur
afed60938f Fox db_stress crash by copying keys before changing sequencenum to zero.
Summary:
The compaction process zeros out sequence numbers if the output is
part of the bottommost level.
The Slice is supposed to refer to an immutable data buffer. The
merger that implements the priority queue while reading kvs as
the input of a compaction run reies on this fact. The bug was that
were updating the sequence number of a record in-place and that was
causing suceeding invocations of the merger to return kvs in
arbitrary order of sequence numbers.
The fix is to copy the key to a local memory buffer before setting
its seqno to 0.

Test Plan:
Set Options.purge_redundant_kvs_while_flush = false and then run
db_stress --ops_per_thread=1000 --max_key=320

Reviewers: emayanke, sheki

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9147
2013-03-06 10:52:08 -08:00
Dhruba Borthakur
f5896681b4 Removed unnecesary file object in table_cache.
Summary:
TableCache->file is not used. remove it.
I kept the TableAndFile structure and will clean it up in a future patch.

Test Plan: make clean check

Reviewers: sheki, chip

Reviewed By: chip

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9075
2013-03-04 13:56:23 -08:00
Mark Callaghan
993543d1be Add rate_delay_limit_milliseconds
Summary:
This adds the rate_delay_limit_milliseconds option to make the delay
configurable in MakeRoomForWrite when the max compaction score is too high.
This delay is called the Ln slowdown. This change also counts the Ln slowdown
per level to make it possible to see where the stalls occur.

From IO-bound performance testing, the Level N stalls occur:
* with compression -> at the largest uncompressed level. This makes sense
                      because compaction for compressed levels is much
                      slower. When Lx is uncompressed and Lx+1 is compressed
                      then files pile up at Lx because the (Lx,Lx+1)->Lx+1
                      compaction process is the first to be slowed by
                      compression.
* without compression -> at level 1

Task ID: #1832108

Blame Rev:

Test Plan:
run with real data, added test

Revert Plan:

Database Impact:

Memcache Impact:

Other Notes:

EImportant:

- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D9045
2013-03-04 07:41:15 -08:00
Dhruba Borthakur
806e264350 Ability for rocksdb to compact when flushing the in-memory memtable to a file in L0.
Summary:
Rocks accumulates recent writes and deletes in the in-memory memtable.
When the memtable is full, it writes the contents on the memtable to
a file in L0.

This patch removes redundant records at the time of the flush. If there
are multiple versions of the same key in the memtable, then only the
most recent one is dumped into the output file. The purging of
redundant records occur only if the most recent snapshot is earlier
than the earliest record in the memtable.

Should we switch on this feature by default or should we keep this feature
turned off in the default settings?

Test Plan: Added test case to db_test.cc

Reviewers: sheki, vamsi, emayanke, heyongqiang

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8991
2013-03-04 00:01:47 -08:00
bil
4992633751 enable the ability to set key size in db_bench in rocksdb
Summary:
1. the default value for key size is still 16
2. enable the ability to set the key size via command line --key_size=

Test Plan:
build & run db_banch and pass some value via command line.
verify it works correctly.

Reviewers: sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8943
2013-03-01 14:10:09 -08:00
Abhishek Kona
c41f1e995c Codemod NULL to nullptr
Summary:
scripted NULL to nullptr in
* include/leveldb/
* db/
* table/
* util/

Test Plan: make all check

Reviewers: dhruba, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D9003
2013-02-28 18:04:58 -08:00
Dhruba Borthakur
e45c7a8444 Abilty to support upto a million .sst files in the database
Summary:
There was an artifical limit of 50K files per database. This is
insifficient if the database is 1 TB in size and each file is 2 MB.

Test Plan: make check

Reviewers: sheki, emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8919
2013-02-26 16:27:51 -08:00
Abhishek Kona
a9866b721b Refactor statistics. Remove individual functions like incNumFileOpens
Summary:
Use only the counter mechanism. Do away with
incNumFileOpens, incNumFileClose, incNumFileErrors
s/NULL/nullptr/g in db/table_cache.cc

Test Plan: make clean check

Reviewers: dhruba, heyongqiang, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8841
2013-02-25 13:58:34 -08:00
Abhishek Kona
959337ed5b Measure compaction time.
Summary: just record time consumed in compaction

Test Plan: compile

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8781
2013-02-22 11:38:40 -08:00
Abhishek Kona
ec77366e14 Counters for bytes written and read.
Summary:
* Counters for bytes read and write.
as a part of this diff, I want to=>
* Measure compaction times. @dhruba can you point which function, should
* I time to get Compaction-times. Was looking at CompactRange.

Test Plan: db_test

Reviewers: dhruba, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8763
2013-02-21 16:06:32 -08:00
Vamsi Ponnekanti
6abb30d4d0 [Missed adding cmdline parsing for new flags added in D8685]
Summary:
I had added FLAGS_numdistinct and FLAGS_deletepercent for randomwithverify
but forgot to add cmdline parsing for those flags.

Test Plan:
[nponnekanti@dev902 /data/users/nponnekanti/rocksdb] ./db_bench --benchmarks=randomwithverify --numdistinct=500
LevelDB:    version 1.5
Date:       Thu Feb 21 10:34:40 2013
CPU:        24 * Intel(R) Xeon(R) CPU           X5650  @ 2.67GHz
CPUCache:   12288 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    1000000
RawSize:    110.6 MB (estimated)
FileSize:   62.9 MB (estimated)
Compression: snappy
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
Created bg thread 0x7fbf90bff700
randomwithverify :       4.693 micros/op 213098 ops/sec; ( get:900000 put:80000 del:20000 total:1000000 found:714556)

[nponnekanti@dev902 /data/users/nponnekanti/rocksdb] ./db_bench --benchmarks=randomwithverify --deletepercent=5
LevelDB:    version 1.5
Date:       Thu Feb 21 10:35:03 2013
CPU:        24 * Intel(R) Xeon(R) CPU           X5650  @ 2.67GHz
CPUCache:   12288 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    1000000
RawSize:    110.6 MB (estimated)
FileSize:   62.9 MB (estimated)
Compression: snappy
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
Created bg thread 0x7fe14dfff700
randomwithverify :       4.883 micros/op 204798 ops/sec; ( get:900000 put:50000 del:50000 total:1000000 found:443847)
[nponnekanti@dev902 /data/users/nponnekanti/rocksdb]
[nponnekanti@dev902 /data/users/nponnekanti/rocksdb] ./db_bench --benchmarks=randomwithverify --deletepercent=5 --numdistinct=500
LevelDB:    version 1.5
Date:       Thu Feb 21 10:36:18 2013
CPU:        24 * Intel(R) Xeon(R) CPU           X5650  @ 2.67GHz
CPUCache:   12288 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    1000000
RawSize:    110.6 MB (estimated)
FileSize:   62.9 MB (estimated)
Compression: snappy
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
Created bg thread 0x7fc31c7ff700
randomwithverify :       4.920 micros/op 203233 ops/sec; ( get:900000 put:50000 del:50000 total:1000000 found:445522)

Revert Plan: OK

Task ID: #

Reviewers: dhruba, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8769
2013-02-21 12:26:32 -08:00
Vamsi Ponnekanti
945d2b59b9 [Add randomwithverify benchmark option]
Summary: Added RandomWithVerify benchmark option.

Test Plan:
This whole diff is to test.
[nponnekanti@dev902 /data/users/nponnekanti/rocksdb] ./db_bench --benchmarks=randomwithverify
LevelDB:    version 1.5
Date:       Tue Feb 19 17:50:28 2013
CPU:        24 * Intel(R) Xeon(R) CPU           X5650  @ 2.67GHz
CPUCache:   12288 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    1000000
RawSize:    110.6 MB (estimated)
FileSize:   62.9 MB (estimated)
Compression: snappy
WARNING: Assertions are enabled; benchmarks unnecessarily slow
------------------------------------------------
Created bg thread 0x7fa9c3fff700
randomwithverify :       5.004 micros/op 199836 ops/sec; ( get:900000 put:80000 del:20000 total:1000000 found:711992)

Revert Plan: OK

Task ID: #

Reviewers: dhruba, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D8685
2013-02-21 10:27:02 -08:00
amayank
b2c50f1c3f Fix for the weird behaviour encountered by ldb Get where it could read only the second-latest value
Summary:
Changed the Get and Scan options with openForReadOnly mode to have access to the memtable.
Changed the visibility of NewInternalIterator in db_impl from private to protected so that
the derived class db_impl_read_only can call that in its NewIterator function for the
scan case. The previous approach which changed the default for flush_on_destroy_ from false to true
caused many problems in the unit tests due to empty sst files that it created. All
unit tests pass now.

Test Plan: make clean; make all check; ldb put and get and scans

Reviewers: dhruba, heyongqiang, sheki

Reviewed By: dhruba

CC: kosievdmerwe, zshao, dilipj, kailiu

Differential Revision: https://reviews.facebook.net/D8697
2013-02-20 10:45:52 -08:00
Abhishek Kona
fe10200ddc Introduce histogram in statistics.h
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
2013-02-20 10:43:32 -08:00
amayank
f3901e0647 Revert "Fix for the weird behaviour encountered by ldb Get where it could read only the second-latest value"
This reverts commit 4c696ed001.
2013-02-18 22:32:27 -08:00
Dhruba Borthakur
fd367e677e Fix unit test failure in db_filename.cc
Summary:
    c_test: db/filename.cc:74: std::string leveldb::DescriptorFileName(const string&,....

Test Plan:
  this is a failure in a unit test

Differential Revision: https://reviews.facebook.net/D8667
2013-02-18 21:53:56 -08:00