Commit Graph

640 Commits

Author SHA1 Message Date
Igor Canadi
f7375f39fd Fix double deletes
Summary: While debugging clients compaction issues, I noticed bunch of delete bugs: P16329995. MakeTableName returns sst file with "/" prefix. We also need "/" prefix when we get the files though GetChildren(), so that we can properly dedup the files.

Test Plan: none

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23457
2014-09-25 11:08:16 -07:00
Igor Canadi
21ddcf6e4f Remove allow_thread_local
Summary: See https://reviews.facebook.net/D19365

Test Plan: compiles

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23907
2014-09-24 13:12:16 -07:00
Lei Jin
5e6aee4325 dont create backup_input if compaction filter v2 is not used
Summary:
Compaction creates backup_input iterator even though it only needed
when compaction filter v2 is enabled

Test Plan: make all check

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23769
2014-09-22 10:36:53 -07:00
Venkatesh Radhakrishnan
f44594743f RocksDB: Format uint64 using PRIu64 in db_impl.cc
Summary: Use PRIu64 to format uint64 in a portable manner

Test Plan: Run "make all check"

Reviewers: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23595
2014-09-18 22:19:41 -07:00
Igor Canadi
2fb1fea30f Fix syncronization issues 2014-09-18 10:42:54 -07:00
Lei Jin
a062e1f2c4 SetOptions() for memtable related options
Summary: as title

Test Plan:
make all check
I will think a way to set up stress test for this

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23055
2014-09-17 12:49:13 -07:00
Igor Canadi
dee91c259d WriteThread
Summary: This diff just moves the write thread control out of the DBImpl. I will need this as I will control column family data concurrency by only accessing some data in the write thread. That way, we won't have to lock our accesses to column family hash table (mappings from IDs to CFDs).

Test Plan: make check

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23301
2014-09-12 16:23:58 -07:00
Igor Canadi
540a257f2c Fix WAL synced
Summary: Uhm...

Test Plan: nope

Reviewers: sdong, yhchiang, tnovak, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23343
2014-09-12 16:15:29 -07:00
Igor Canadi
9c0e66ce98 Don't run background jobs (flush, compactions) when bg_error_ is set
Summary:
If bg_error_ is set, that means that we mark DB read only. However, current behavior still continues the flushes and compactions, even though bg_error_ is set.

On the other hand, if bg_error_ is set, we will return Status::OK() from CompactRange(), although the compaction didn't actually succeed.

This is clearly not desired behavior. I found this when I was debugging t5132159, although I'm pretty sure these aren't related.

Also, when we're shutting down, it's dangerous to exit RunManualCompaction(), since that will destruct ManualCompaction object. Background compaction job might still hold a reference to manual_compaction_ and this will lead to undefined behavior. I changed the behavior so that we only exit RunManualCompaction when manual compaction job is marked done.

Test Plan: make check

Reviewers: sdong, ljin, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23223
2014-09-11 16:24:16 -07:00
Igor Canadi
3d9e6f7759 Push model for flushing memtables
Summary:
When memtable is full it calls the registered callback. That callback then registers column family as needing the flush. Every write checks if there are some column families that need to be flushed. This completely eliminates the need for MakeRoomForWrite() function and simplifies our Write code-path.

There is some complexity with the concurrency when the column family is dropped. I made it a bit less complex by dropping the column family from the write thread in https://reviews.facebook.net/D22965. Let me know if you want to discuss this.

Test Plan: make check works. I'll also run db_stress with creating and dropping column families for a while.

Reviewers: yhchiang, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23067
2014-09-10 18:46:09 -07:00
sdong
06d986252a Always pass MergeContext as pointer, not reference
Summary: To follow the coding convention and make sure when passing reference as a parameter it is also const, pass MergeContext as a pointer to mem tables.

Test Plan: make all check

Reviewers: ljin, igor

Reviewed By: igor

Subscribers: leveldb, dhruba, yhchiang

Differential Revision: https://reviews.facebook.net/D23085
2014-09-09 11:37:32 -07:00
Stanislau Hlebik
d343c3fe46 Improve db recovery
Summary: Avoid creating unnecessary sst files while db opening

Test Plan: make all check

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: zagfox, yhchiang, ljin, leveldb

Differential Revision: https://reviews.facebook.net/D20661
2014-09-09 11:18:50 -07:00
Lei Jin
52311463e9 MemTableOptions
Summary: removed reference to options in WriteBatch and DBImpl::Get()

Test Plan: make all check

Reviewers: yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23049
2014-09-08 18:46:52 -07:00
Lei Jin
659d2d50c3 move compaction_filter to immutable_options
Summary:
all shared_ptrs are in immutable_options now. This will also make
options assignment a little cheaper

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23001
2014-09-08 15:09:25 -07:00
Lei Jin
048560a642 reduce references to cfd->options() in DBImpl
Summary:
I found it is almost impossible to get rid of this function in a single
batch. I will take a step by step approach

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22995
2014-09-08 15:04:34 -07:00
sdong
011241bb99 DB::Flush() Do not wait for background threads when there is nothing in mem table
Summary:
When we have multiple column families, users can issue Flush() on every column families to make sure everything is flushes, even if some of them might be empty. By skipping the waiting for empty cases, it can be greatly speed up.

Still wait for people's comments before writing unit tests for it.

Test Plan: Will write a unit test to make sure it is correct.

Reviewers: ljin, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D22953
2014-09-08 13:40:42 -07:00
Igor Canadi
a2bb7c3c33 Push- instead of pull-model for managing Write stalls
Summary:
Introducing WriteController, which is a source of truth about per-DB write delays. Let's define an DB epoch as a period where there are no flushes and compactions (i.e. new epoch is started when flush or compaction finishes). Each epoch can either:
* proceed with all writes without delay
* delay all writes by fixed time
* stop all writes

The three modes are recomputed at each epoch change (flush, compaction), rather than on every write (which is currently the case).

When we have a lot of column families, our current pull behavior adds a big overhead, since we need to loop over every column family for every write. With new push model, overhead on Write code-path is minimal.

This is just the start. Next step is to also take care of stalls introduced by slow memtable flushes. The final goal is to eliminate function MakeRoomForWrite(), which currently needs to be called for every column family by every write.

Test Plan: make check for now. I'll add some unit tests later. Also, perf test.

Reviewers: dhruba, yhchiang, MarkCallaghan, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22791
2014-09-08 11:20:25 -07:00
Igor Canadi
9f1c80b556 Drop column family from write thread
Summary: If we drop column family only from (single) write thread, we can be sure that nobody will drop the column family while we're writing (and our mutex is released). This greatly simplifies my patch that's getting rid of MakeRoomForWrite().

Test Plan: make check, but also running stress test

Reviewers: ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22965
2014-09-05 15:20:05 -07:00
Lei Jin
c9e419ccb6 rename options_ to db_options_ in DBImpl to avoid confusion
Summary: as title

Test Plan: make release

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22935
2014-09-05 11:48:17 -07:00
liuhuahang
bb6ae0f80c fix more compile warnings
N/A

Change-Id: I5b6f9c70aea7d3f3489328834fed323d41106d9f
Signed-off-by: liuhuahang <liuhuahang@zerus.co>
2014-09-05 14:14:37 +08:00
Stanislau Hlebik
45a5e3ede0 Remove path with arena==nullptr from NewInternalIterator
Summary:
Simply code by removing code path which does not use Arena
from NewInternalIterator

Test Plan:
make all check
make valgrind_check

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22395
2014-09-04 17:40:41 -07:00
Lei Jin
5665e5e285 introduce ImmutableOptions
Summary:
As a preparation to support updating some options dynamically, I'd like
to first introduce ImmutableOptions, which is a subset of Options that
cannot be changed during the course of a DB lifetime without restart.

ColumnFamily will keep both Options and ImmutableOptions. Any component
below ColumnFamily should only take ImmutableOptions in their
constructor. Other options should be taken from APIs, which will be
allowed to adjust dynamically.

I am yet to make changes to memtable and other related classes to take
ImmutableOptions in their ctor. That can be done in a seprate diff as
this one is already pretty big.

Test Plan: make all check

Reviewers: yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D22545
2014-09-04 16:18:36 -07:00
Raghav Pisolkar
e0b99d4f5d created a new ReadOptions parameter 'iterate_upper_bound' 2014-09-04 11:00:16 -07:00
Lei Jin
9b58c73c7c call SanitizeDBOptionsByCFOptions() in the right place
Summary: It only covers Open() with default column family right now

Test Plan: make release

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22467
2014-09-02 14:42:23 -07:00
Igor Canadi
a84234a61b Ignore missing column families
Summary:
Before this diff, whenever we Write to non-existing column family, Write() would fail.

This diff adds an option to not fail a Write() when WriteBatch points to non-existing column family. MongoDB said this would be useful for them, since they might have a transaction updating an index that was dropped by another thread. This way, they don't have to worry about checking if all indexes are alive on every write. They don't care if they lose writes to dropped index.

Test Plan: added a small unit test

Reviewers: sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22143
2014-09-02 13:29:05 -07:00
Igor Canadi
7f19bb93c6 Merge pull request #242 from tdfischer/perf-timer-destructors
Refactor PerfStepTimer to automatically stop on destruct
2014-09-02 13:06:40 -07:00
Feng Zhu
8438a19360 fix dropping column family bug
Summary: 1. db/db_impl.cc:2324 (DBImpl::BackgroundCompaction) should not raise bg_error_ when column family is dropped during compaction.

Test Plan: 1. db_stress

Reviewers: ljin, yhchiang, dhruba, igor, sdong

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22653
2014-09-02 12:25:58 -07:00
Torrie Fischer
6614a48418 Refactor PerfStepTimer to stop on destruct
This eliminates the need to remember to call PERF_TIMER_STOP when a section has
been timed. This allows more useful design with the perf timers and enables
possible return value optimizations. Simplistic example:

class Foo {
  public:
    Foo(int v) : m_v(v);
  private:
    int m_v;
}

Foo makeFrobbedFoo(int *errno)
{
  *errno = 0;
  return Foo();
}

Foo bar(int *errno)
{
  PERF_TIMER_GUARD(some_timer);

  return makeFrobbedFoo(errno);
}

int main(int argc, char[] argv)
{
  Foo f;
  int errno;

  f = bar(&errno);

  if (errno)
    return -1;
  return 0;
}

After bar() is called, perf_context.some_timer would be incremented as if
Stop(&perf_context.some_timer) was called at the end, and the compiler is still
able to produce optimizations on the return value from makeFrobbedFoo() through
to main().
2014-09-02 12:04:22 -07:00
Igor Canadi
7dcadb1d37 Don't let flush preempt compaction in certain cases
Summary:
I have an application configured with 16 background threads. Write rates are high. L0->L1 compactions is very slow and it limits the concurrency of the system. While it's happening, other 15 threads are idle. However, when there is a need of a flush, that one thread busy with L0->L1 is doing flush, instead of any other 15 threads that are just sitting there.

This diff prevents that. If there are threads that are idle, we don't let flush preempt compaction.

Test Plan: Will run stress test

Reviewers: ljin, sdong, yhchiang

Reviewed By: sdong, yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D22299
2014-09-02 08:34:54 -07:00
Nik Bougalis
f09329cb01 Fix candidate file comparison when using path ids 2014-08-31 00:54:15 -07:00
Lei Jin
722d80c374 reduce recordTick overhead in compaction loop
Summary: It is too expensive to bump ticker to every key/vaue pair

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22527
2014-08-29 09:51:09 -07:00
Igor Canadi
d977e55596 Don't let other compactions run when manual compaction runs
Summary:
Based on discussions from t4982833. This is just a short-term fix, I plan to revamp manual compaction process as part of t4982812.

Also, I think we should schedule automatic compactions at the very end of manual compactions, not when we're done with one level. I made that change as part of this diff. Let me know if you disagree.

Test Plan: make check for now

Reviewers: sdong, tnovak, yhchiang, ljin

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22401
2014-08-28 13:06:28 -04:00
Igor Canadi
d5bd6c772b Fix ios compile
Summary: No __thread for ios.

Test Plan: compile works for ios now

Reviewers: ljin, dhruba

Reviewed By: dhruba

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22491
2014-08-28 12:46:05 -04:00
Stanislau Hlebik
9dcb75b6d9 Add is-file-deletions-enabled property
Summary:
Add property 'rocksdb.is-file-deletions-enable'
	 which equals disable_delete_obsole_file_

Test Plan: make all check

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22119
2014-08-26 16:26:29 -07:00
Lei Jin
23861857c4 ReadOptions.total_order_seek to allow total order seek for block-based table when hash index is enabled
Summary: as title

Test Plan: table_test

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22239
2014-08-25 16:14:30 -07:00
Lei Jin
384400128f move block based table related options BlockBasedTableOptions
Summary:
I will move compression related options in a separate diff since this
diff is already pretty lengthy.
I guess I will also need to change JNI accordingly :(

Test Plan: make all check

Reviewers: yhchiang, igor, sdong

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21915
2014-08-25 14:22:05 -07:00
Yueh-Hsuan Chiang
63a2215c63 Improve Options sanitization and add MmapReadRequired() to TableFactory
Summary:
Currently, PlainTable must use mmap_reads.  When PlainTable is used but
allow_mmap_reads is not set, rocksdb will fail in flush.

This diff improve Options sanitization and add MmapReadRequired() to
TableFactory.

Test Plan:
export ROCKSDB_TESTS=PlainTableOptionsSanitizeTest
make db_test -j32
./db_test

Reviewers: sdong, ljin

Reviewed By: ljin

Subscribers: you, leveldb

Differential Revision: https://reviews.facebook.net/D21939
2014-08-20 15:53:39 -07:00
sdong
10720a5587 Revert the unintended change that DestroyDB() doesn't clean up info logs.
Summary: A previous change triggered a change by mistake: DestroyDB() will keep info logs under DB directory. Revert the unintended change.

Test Plan: Add a unit test case to verify it.

Reviewers: ljin, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22209
2014-08-20 12:07:32 -07:00
Igor Canadi
c8ecfaedd0 Merge pull request #230 from cockroachdb/spencerkimball/send-user-keys-to-v2-filter
Pass parsed user key to prefix extractor in V2 compaction
2014-08-18 11:09:30 -04:00
sdong
58b0f9d890 Support purging logs from separate log directory
Summary:
1. Support purging info logs from a separate paths from DB path. Refactor the codes of generating info log prefixes so that it can be called when generating new files and scanning log directory.
2. Fix the bug of not scanning multiple DB paths (should only impact multiple DB paths)

Test Plan:
Add unit test for generating and parsing info log files
Add end-to-end test in db_test

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb, igor, dhruba

Differential Revision: https://reviews.facebook.net/D21801
2014-08-14 13:22:50 -07:00
Feng Zhu
5e642403a9 log db path info before open
Summary: 1. write db MANIFEST, CURRENT, IDENTITY, sst files, log files to log before open

Test Plan: run db and check LOG file

Reviewers: ljin, yhchiang, igor, dhruba, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21459
2014-08-13 13:45:13 -07:00
sdong
48081777f3 Revert "Include candidate files under options.db_log_dir in FindObsoleteFiles()"
This reverts commit 54153ab07a.
2014-08-12 18:14:27 -07:00
Lei Jin
218857b3f5 remove tailing_iter.h/cc
Summary: as title

Test Plan:
make all check
ran db_bench and saw seek stats at the end

Reviewers: yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21651
2014-08-12 17:13:15 -07:00
Lei Jin
5d0074c471 set bytes_per_sync to 1MB if rate limiter is enabled
Summary: as title

Test Plan: make all check

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21201
2014-08-12 16:42:18 -07:00
Spencer Kimball
3fcf7b26b9 Pass parsed user key to prefix extractor in V2 compaction
Previously, the prefix extractor was being supplied with the RocksDB
key instead of a parsed user key. This makes correct interpretation
by calling application fragile or impossible.
2014-08-12 18:48:28 -04:00
Stanislau Hlebik
2fa643466d Add scope guard
Summary: Small change: replace mutex_.Lock/mutex_.Unlock() with scope guard

Test Plan: make all check

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21609
2014-08-12 12:13:13 -07:00
Stanislau Hlebik
06a52bda64 Flush only one column family
Summary:
Currently DBImpl::Flush() triggers flushes in all column families.
Instead we need to trigger just the column family specified.

Test Plan: make all check

Reviewers: igor, ljin, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D20841
2014-08-11 22:10:32 -07:00
miguelportilla
93e6b5e9d9 Changes to support unity build:
* Script for building the unity.cc file via Makefile
* Unity executable Makefile target for testing builds
* Source code changes to fix compilation of unity build
2014-08-11 13:22:47 -04:00
sdong
54153ab07a Include candidate files under options.db_log_dir in FindObsoleteFiles()
Summary: In FindObsoleteFiles(), we don't scan db_log_dir. Add it.

Test Plan: make all check

Reviewers: ljin, igor, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb, yhchiang

Differential Revision: https://reviews.facebook.net/D21429
2014-08-08 17:37:03 -07:00
sdong
4632239d13 Need to schedule compactions when manual compaction finishes
Summary: If there is an outstanding compaction scheduled but at the time a manual compaction is triggered, the manual compaction will preempt. In the end of the manual compaction, we should try to schedule compactions to make sure those preempted ones are not skipped.

Test Plan: make all check

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb, dhruba, igor

Differential Revision: https://reviews.facebook.net/D21321
2014-08-08 12:28:36 -07:00
Igor Canadi
5e0868147d Fix SIGSEGV in travis
Summary:
Travis build was failing a lot. For example see https://travis-ci.org/facebook/rocksdb/builds/31425845

This fixes it.

Also, please don't put any code after SignalAll :)

Test Plan: no more SIGSEGV

Reviewers: yhchiang, sdong, ljin

Reviewed By: ljin

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D21417
2014-08-08 10:24:00 -07:00
Igor Canadi
f8d6a2981f Merge pull request #224 from cockroachdb/spencerkimball/compaction-filter-v2-c-bindings
Add support for C bindings to the compaction V2 filter mechanism.
2014-08-07 14:10:54 -04:00
sdong
7abe9655d3 Fix valgrind failure caused by recent checked-in.
Summary: Initialize un-initialized parameters

Test Plan: run the failed test (c_test)

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21249
2014-08-06 17:45:47 -07:00
Spencer Kimball
38e8b727a8 Fix typo, add missing inclusion of state void* in invocation of
create_compaction_filter_v2_.
2014-08-06 18:42:15 -04:00
Spencer Kimball
c1f588af71 Add support for C bindings to the compaction V2 filter mechanism.
Test Plan: make c_test && ./c_test

Some fixes after merge.
2014-08-06 15:55:48 -04:00
sdong
1242bfcad7 Add DB property "rocksdb.estimate-table-readers-mem"
Summary:
Add a DB Property "rocksdb.estimate-table-readers-mem" to return estimated memory usage by all loaded table readers, other than allocated from block cache.

Refactor the property codes to allow getting property from a version, with DB mutex not acquired.

Test Plan: Add several checks of this new property in existing codes for various cases.

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: xjin, igor, leveldb

Differential Revision: https://reviews.facebook.net/D20733
2014-08-06 11:39:46 -07:00
Feng Zhu
1129921e9b logging_when_create_and_delete_manifest
Summary:
  1. logging when create and delete manifest file
  2. fix formating in table/format.cc

Test Plan:
  make all check
  run db_bench, track the LOG file.

Reviewers: ljin, yhchiang, igor, yufei.zhu, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21009
2014-08-04 11:25:42 -07:00
Igor Canadi
e4c3673923 Never CompactRange to level 0 in level compaction
Summary: I was bit by this when developing SpatialDB. In case all files are at level 0, CompactRange() will output the compacted files to level 0. This is not ideal, since read amp. is much better at level 1 and higher.

Test Plan: Compacted data in SpatialDB, read manifest using ldb, verified that files are now at level 1 instead of 0.

Reviewers: sdong, ljin, yhchiang, dhruba

Reviewed By: dhruba

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D20901
2014-08-01 06:41:48 -07:00
Yueh-Hsuan Chiang
49ee5a4ac4 Fixed the crash when merge_operator is not properly set after reopen.
Summary:
Fixed the crash when merge_operator is not properly set after reopen
and added two test cases for this.

Test Plan:
make merge_test
./merge_test

Reviewers: igor, ljin, sdong

Reviewed By: sdong

Subscribers: benj, mvikjord, leveldb

Differential Revision: https://reviews.facebook.net/D20793
2014-07-30 17:24:36 -07:00
sdong
f04356e660 Add DB::GetIntProperty() to return integer properties to be returned as integers
Summary: We have quite some properties that are integers and we are adding more. Add a function to directly return them as an integer, instead of a string

Test Plan: Add several unit test checks

Reviewers: yhchiang, igor, dhruba, haobo, ljin

Reviewed By: ljin

Subscribers: yoshinorim, leveldb

Differential Revision: https://reviews.facebook.net/D20637
2014-07-28 16:55:57 -07:00
Lei Jin
7e8bb71dd0 InternalStats to take cfd on constructor
Summary:
It has one-to-one relationship with CFD. Take a pointer to CFD on
constructor to avoid passing cfd through member functions.

Test Plan: make

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D20565
2014-07-28 12:27:08 -07:00
Lei Jin
1bd3431f7c Change StopWatch interface
Summary: So that we can avoid calling NowSecs() in MakeRoomForWrite twice

Test Plan: make all check

Reviewers: yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D20529
2014-07-28 12:22:37 -07:00
Lei Jin
f6ca226c17 make statistics forward-able
Summary:
Make StatisticsImpl being able to forward stats to provided statistics
implementation. The main purpose is to allow us to collect internal
stats in the future even when user supplies custom statistics
implementation. It avoids intrumenting 2 sets of stats collection code.
One immediate use case is tuning advisor, which needs to collect some
internal stats, users may not be interested.

Test Plan:
ran db_bench and see stats show up at the end of run
Will run make all check since some tests rely on statistics

Reviewers: yhchiang, sdong, igor

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D20145
2014-07-28 12:10:49 -07:00
Lei Jin
40fa8a4cd5 make statistics forward-able
Summary:
Make StatisticsImpl being able to forward stats to provided statistics
implementation. The main purpose is to allow us to collect internal
stats in the future even when user supplies custom statistics
implementation. It avoids intrumenting 2 sets of stats collection code.
One immediate use case is tuning advisor, which needs to collect some
internal stats, users may not be interested.

Test Plan:
ran db_bench and see stats show up at the end of run
Will run make all check since some tests rely on statistics

Reviewers: yhchiang, sdong, igor

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D20145
2014-07-28 12:05:36 -07:00
sdong
f6b7e1ed1a Allow user to specify DB path of output file of manual compaction
Summary: Add a parameter path_id to DB::CompactRange(), to indicate where the output file should be placed to.

Test Plan: add a unit test

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: xjin, igor, dhruba, MarkCallaghan, leveldb

Differential Revision: https://reviews.facebook.net/D20085
2014-07-21 19:06:00 -07:00
Lei Jin
f6f1533c6f make internal stats independent of statistics
Summary:
also make it aware of column family
output from db_bench

```
** Compaction Stats [default] **
Level Files Size(MB) Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) RW-Amp W-Amp Rd(MB/s) Wr(MB/s)  Rn(cnt) Rnp1(cnt) Wnp1(cnt) Wnew(cnt)  Comp(sec) Comp(cnt) Avg(sec) Stall(sec) Stall(cnt) Avg(ms)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0    14      956   0.9      0.0     0.0      0.0       2.7      2.7    0.0   0.0      0.0    111.6        0         0         0         0         24        40    0.612      75.20     492387    0.15
  L1    21     2001   2.0      5.7     2.0      3.7       5.3      1.6    5.4   2.6     71.2     65.7       31        43        55        12         82         2   41.242      43.72      41183    1.06
  L2   217    18974   1.9     16.5     2.0     14.4      15.1      0.7   15.6   7.4     70.1     64.3       17       182       185         3        241        16   15.052       0.00          0    0.00
  L3  1641   188245   1.8      9.1     1.1      8.0       8.5      0.5   15.4   7.4     61.3     57.2        9        75        76         1        152         9   16.887       0.00          0    0.00
  L4  4447   449025   0.4     13.4     4.8      8.6       9.1      0.5    4.7   1.9     77.8     52.7       38        79       100        21        176        38    4.639       0.00          0    0.00
 Sum  6340   659201   0.0     44.7    10.0     34.7      40.6      6.0   32.0  15.2     67.7     61.6       95       379       416        37        676       105    6.439     118.91     533570    0.22
 Int     0        0   0.0      1.2     0.4      0.8       1.3      0.5    5.2   2.7     59.1     65.6        3         7         9         2         20        10    2.003       0.00          0    0.00
Stalls(secs): 75.197 level0_slowdown, 0.000 level0_numfiles, 0.000 memtable_compaction, 43.717 leveln_slowdown
Stalls(count): 492387 level0_slowdown, 0 level0_numfiles, 0 memtable_compaction, 41183 leveln_slowdown

** DB Stats **
Uptime(secs): 202.1 total, 13.5 interval
Cumulative writes: 6291456 writes, 6291456 batches, 1.0 writes per batch, 4.90 ingest GB
Cumulative WAL: 6291456 writes, 6291456 syncs, 1.00 writes per sync, 4.90 GB written
Interval writes: 1048576 writes, 1048576 batches, 1.0 writes per batch, 836.0 ingest MB
Interval WAL: 1048576 writes, 1048576 syncs, 1.00 writes per sync, 0.82 MB written

Test Plan: ran it

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19917
2014-07-21 12:57:29 -07:00
Yueh-Hsuan Chiang
3178510153 Allow class Compaction to handle input files from multiple levels.
Summary:
Allow class Compaction to handle input files from multiple levels.
This diff is a subset of https://reviews.facebook.net/D19263 where
only db/compaction.cc and db/compaction.h are changed.

Test Plan:
make db_test
export ROCKSDB_TESTS=Compaction
./db_test

Reviewers: igor, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19923
2014-07-17 14:36:41 -07:00
Feng Zhu
87895c62db fix bug in LOG for flush memtable
Summary:
  One line change to fix a bug in the LOG when flush memtable

Test Plan:
  NONE

Reviewers: sdong

Reviewed By: sdong

Differential Revision: https://reviews.facebook.net/D20049
2014-07-16 16:56:49 -07:00
sdong
0abaed2e08 Support multiple DB directories in universal compaction style
Summary:
This patch adds a target size parameter in options.db_paths and universal compaction will base it to determine which DB path to place a new file.
Level-style stays the same.

Test Plan: Add new unit tests

Reviewers: ljin, yhchiang

Reviewed By: yhchiang

Subscribers: MarkCallaghan, dhruba, igor, leveldb

Differential Revision: https://reviews.facebook.net/D19869
2014-07-15 12:06:28 -07:00
Igor Canadi
20c056306b Remove stats logger
Summary: Browsing through the code, looks like StatsLogger is not used at all!

Test Plan: compiles

Reviewers: ljin, sdong, yhchiang, dhruba

Reviewed By: dhruba

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D19827
2014-07-15 09:16:32 -04:00
Lei Jin
46f0f6ddd5 improve InternalStats output
Summary: as title

Test Plan:
sampe output:
Level Files Size(MB) Score Read(GB)  Rn(GB) Rnp1(GB) Write(BG) Wnew(GB) RW-Amp W-Amp Rd(MB/s) Wr(MB/s)  Rn(cnt) Rnp1(cnt) Wnp1(cnt) Wnew(cnt)  Comp(sec) Comp(cnt) Avg(sec) Stall(sec) Stall(cnt) Avg(ms)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0    15     1024   1.0      0.0     0.0      0.0       8.2      8.2    0.0   0.0      0.0    111.4        0         0         1         1         75       123    0.612     295.94    1939238    0.15
  L1    23     2118   2.1     20.9     8.3     12.7      20.0      7.3    5.0   2.4     73.2     69.9      124       141       208        67        293         8   36.582      17.05      16100    1.06
  L2   162    15333   1.5     47.0     7.1     40.0      42.6      2.6   12.7   6.0     67.9     61.5       62       457       482        25        709        55   12.898       0.00          0    0.00
  L3   985   108065   1.1     37.8     4.0     33.9      36.9      3.0   18.8   9.3     60.1     58.5       41       338       363        25        645        31   20.812       0.00          0    0.00
  L4  2788   356033   0.3      0.0     0.0      0.0       0.0      0.0    0.0   0.0      0.0      0.0        0         0         0         0          0         0    0.000       0.00          0    0.00
 Sum  3973   482572   0.0    105.8    19.3     86.5     107.7     21.2   11.1   5.6     62.9     64.0      227       936      1054       118       1723       217    7.938     312.99    1955338    0.16

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19707
2014-07-11 15:03:30 -07:00
Feng Zhu
178fd6f9db use FileLevel in LevelFileNumIterator
Summary:
  Use FileLevel in LevelFileNumIterator, thus use new version of findFile.
  Old version of findFile function is deleted.
  Write a function in version_set.cc to generate FileLevel from files_.
  Add GenerateFileLevelTest in version_set_test.cc

Test Plan:
  make all check

Reviewers: ljin, haobo, yhchiang, sdong

Reviewed By: sdong

Subscribers: igor, dhruba

Differential Revision: https://reviews.facebook.net/D19659
2014-07-11 12:52:41 -07:00
Lei Jin
534357ca3a integrate rate limiter into rocksdb
Summary:
Add option and plugin rate limiter for PosixWritableFile. The rate
limiter only applies to flush and compaction. WAL and MANIFEST are
excluded from this enforcement.

Test Plan: db_test

Reviewers: igor, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19425
2014-07-08 12:31:49 -07:00
Yueh-Hsuan Chiang
d33657a4a5 Fixed a warning in release mode.
Summary: Removed a variable that is only used in assertion check.

Test Plan: make release

Reviewers: ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19455
2014-07-03 17:19:17 -07:00
Yueh-Hsuan Chiang
90a6aca48e Finer report I/O stats about Flush and Compaction.
Summary:
This diff allows the I/O stats about Flush and Compaction to be reported
in a more accurate way.  Instead of measuring the size of a file, it
measure I/O cost in per read / write basis.

Test Plan: make all check

Reviewers: sdong, igor, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19383
2014-07-03 16:28:03 -07:00
Yueh-Hsuan Chiang
d4d338de33 Add timeout_hint_us to WriteOptions and introduce Status::TimeOut.
Summary:
This diff adds timeout_hint_us to WriteOptions.  If it's non-zero, then
1) writes associated with this options MAY be aborted when it has been
  waiting for longer than the specified time.  If an abortion happens,
  associated writes will return Status::TimeOut.
2) the stall time of the associated write caused by flush or compaction
  will be limited by timeout_hint_us.

The default value of timeout_hint_us is 0 (i.e., OFF.)

The statistics of timeout writes will be recorded in WRITE_TIMEDOUT.

Test Plan:
export ROCKSDB_TESTS=WriteTimeoutAndDelayTest
make db_test
./db_test

Reviewers: igor, ljin, haobo, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D18837
2014-07-03 15:47:02 -07:00
sdong
2459f7ec4e Support Multiple DB paths (without having an interface to expose to users)
Summary:
In this patch, we allow RocksDB to support multiple DB paths internally.
No user interface is supported yet so this patch is silent to users.

Test Plan: make all check

Reviewers: igor, haobo, ljin, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D18921
2014-07-02 21:14:44 -07:00
Igor Canadi
f146cab261 Centralize compression decision to compaction picker
Summary:
Before this diff, we're deciding enable_compression in CompactionPicker and then we're deciding final compression type in DBImpl. This is kind of confusing.

After the diff, the final compression type will be decided in CompactionPicker.

The reason for this is that I want CompactFiles() to specify output compression type, so that people can mix and match compression styles in their compaction algorithms. This diff makes it much easier to do that.

Test Plan: make check

Reviewers: dhruba, haobo, sdong, yhchiang, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19137
2014-07-02 20:40:57 +02:00
sdong
dd337bc0b2 In logging format, use PRIu64 instead of casting
Summary: Code cleaning up, since we are already using __STDC_FORMAT_MACROS in printing uint64_t, change other places. Only logging is changed.

Test Plan: make all check

Reviewers: ljin

Reviewed By: ljin

Subscribers: dhruba, yhchiang, haobo, leveldb

Differential Revision: https://reviews.facebook.net/D19113
2014-06-27 16:34:15 -07:00
Stanislau Hlebik
a3594867ba Cache some conditions for DBImpl::MakeRoomForWrite
Summary:
Task 4580155. Some conditions in DBImpl::MakeRoomForWrite can be cached in
ColumnFamilyData, because theirs value can be changed only during compaction,
adding new memtable and/or add recalculation of compaction score.

These conditions are:

cfd->imm()->size() ==  cfd->options()->max_write_buffer_number - 1
cfd->current()->NumLevelFiles(0) >=  cfd->options()->level0_stop_writes_trigger
cfd->options()->soft_rate_limit > 0.0 &&
    (score = cfd->current()->MaxCompactionScore()) >  cfd->options()->soft_rate_limit
cfd->options()->hard_rate_limit > 1.0 &&
    (score = cfd->current()->MaxCompactionScore()) >  cfd->options()->hard_rate_limit

P.S.
As it's my first diff, Siying suggested to add everybody as a reviewers
for this diff. Sorry, if I forgot someone or add someone by mistake.

Test Plan: make all check

Reviewers: haobo, xjin, dhruba, yhchiang, zagfox, ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19311
2014-06-26 16:45:27 -07:00
Igor Canadi
d4a8423334 Remove seek compaction
Summary:
As discussed in our internal group, we don't get much use of seek compaction at the moment, while it's making code more complicated and slower in some cases.

This diff removes seek compaction and (hopefully) all code that was introduced to support seek compaction.

There is one test case that relied on didIO information. I'll try to find another way to implement it.

Test Plan: make check

Reviewers: sdong, haobo, yhchiang, ljin, dhruba

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19161
2014-06-20 10:23:02 +02:00
Yueh-Hsuan Chiang
4f5ccfd179 Fixed a potential write hang
Summary:
Currently, when something badly happen in the DB::Write() while the write-queue
contains more than one element, the current design seems to forget to clean up
the queue as well as wake-up all the writers, this potentially makes rocksdb
hang on writes.

Test Plan: make all check

Reviewers: sdong, ljin, igor, haobo

Reviewed By: haobo

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19167
2014-06-19 14:53:03 -07:00
Lei Jin
c4e90c79ed bug fix: iteration over ColumnFamilySet needs to be under mutex
Summary: asan_crash_test is failing on segfault

Test Plan: running asan_crash_test

Reviewers: sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19149
2014-06-19 09:31:14 -07:00
sdong
cadc1adffa Refactor: group metadata needed to open an SST file to a separate copyable struct
Summary:
We added multiple fields to FileMetaData recently and are planning to add more.
This refactoring separate the minimum information for accessing the file. This object is copyable (FileMetaData is not copyable since the ref counter). I hope this refactoring can enable further improvements:

(1) use it to design a more efficient data structure to speed up read queries.
(2) in the future, when we add information of storage level, we can easily do the encoding, instead of enlarge this structure, which might expand memory work set for file meta data.

The definition is same as current EncodedFileMetaData used in two level iterator, so now the logic in two level iterator is easier to understand.

Test Plan: make all check

Reviewers: haobo, igor, ljin

Reviewed By: ljin

Subscribers: leveldb, dhruba, yhchiang

Differential Revision: https://reviews.facebook.net/D18933
2014-06-16 16:10:52 -07:00
Igor Canadi
a0191c9dfe Create Missing Column Families
Summary: Provide an convenience option to create column families if they are missing from the DB. Task #4460490

Test Plan: added unit test. also, stress test for some time

Reviewers: sdong, haobo, dhruba, ljin, yhchiang

Reviewed By: yhchiang

Subscribers: yhchiang, leveldb

Differential Revision: https://reviews.facebook.net/D18951
2014-06-06 18:04:56 -07:00
Igor Canadi
99d3eed2fd Write Fast-path for single column family
Summary: We have a perf regression of Write() even with one column family. Make fast path for single column family to avoid the perf regression. See task #4455480

Test Plan: make check

Reviewers: sdong, ljin

Reviewed By: sdong, ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18963
2014-06-06 17:26:23 -07:00
Igor Canadi
5d870717ae Correctly preallocate files in universal compaction
Summary: In universal compaction, MaxFileSizeForLevel is ULLONG_MAX. We've been preallocation files to UULONG_MAX size all these time :)

Test Plan: make check

Reviewers: dhruba, haobo, ljin, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18915
2014-06-05 13:19:35 -07:00
Igor Canadi
fd27001072 Fix compile errors on Mac
Summary: https://phabricator.fb.com/P11372644

Test Plan: compiles

Reviewers: sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18873
2014-06-03 12:28:58 -07:00
sdong
df9069d23f In DB::NewIterator(), try to allocate the whole iterator tree in an arena
Summary:
In this patch, try to allocate the whole iterator tree starting from DBIter from an arena
1. ArenaWrappedDBIter is created when serves as the entry point of an iterator tree, with an arena in it.
2. Add an option to create iterator from arena for following iterators: DBIter, MergingIterator, MemtableIterator, all mem table's iterators, all table reader's iterators and two level iterator.
3. MergeIteratorBuilder is created to incrementally build the tree of internal iterators. It is passed to mem table list and version set and add iterators to it.

Limitations:
(1) Only DB::NewIterator() without tailing uses the arena. Other cases, including readonly DB and compactions are still from malloc
(2) Two level iterator itself is allocated in arena, but not iterators inside it.

Test Plan: make all check

Reviewers: ljin, haobo

Reviewed By: haobo

Subscribers: leveldb, dhruba, yhchiang, igor

Differential Revision: https://reviews.facebook.net/D18513
2014-06-02 17:44:57 -07:00
Igor Canadi
91ddd587cc Only signal cond variable if need to
Summary:
At the end of BackgroundCallCompaction(), we call SignalAll(), even though we don't need to. If compaction hasn't done anything and there's another compaction running, there is no need to signal on the condition variable. Doing so creates a tight feedback loop which results in log files like:

   wait for memtable flush
   compaction nothing to do
   wait for memtable flush
   compaction nothing to do

This change eliminates that

Test Plan:
make check
Also:

    icanadi@dev1440 ~ $ grep "nothing to do" /fast-rocksdb-tmp/rocksdb_test/column_family_test/LOG | wc -l
    7435
    icanadi@dev1440 ~ $ grep "nothing to do" /fast-rocksdb-tmp/rocksdb_test/column_family_test/LOG | wc -l
    372

First version is before the change, second version is after the change.

Reviewers: dhruba, ljin, haobo, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18855
2014-06-02 17:23:55 -07:00
Igor Canadi
8cb7ad83c3 Flush stale column families less aggressively
Summary:
We've seen some production issues where column family is detected as stale, although there is only one column family in the system. This is a quick fix that:
1) doesn't flush stale column families if there's only one of them
2) Use 4 as a coefficient instead of 2 for determening when a column family is stale. This will make flushing less aggressive, while still keep a nice dynamic flushing of very stale CFs.

Test Plan: make check

Reviewers: dhruba, haobo, ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D18861
2014-06-02 15:33:54 -07:00
Lei Jin
388d2054c7 forward iterator
Summary:
Forward iterator puts everything together in a flat structure instead of
a hierarchy of nested iterators. this should simplify the code and
provide better performance. It also enables more optimization since all
information are accessiable in one place.
Init evaluation shows about 6% improvement

Test Plan: db_test and db_bench

Reviewers: dhruba, igor, tnovak, sdong, haobo

Reviewed By: haobo

Subscribers: sdong, leveldb

Differential Revision: https://reviews.facebook.net/D18795
2014-05-30 14:31:55 -07:00
Igor Canadi
6de6a06631 FIFO compaction style
Summary:
Introducing new compaction style -- FIFO.

FIFO compaction style has write amplification of 1 (+1 for WAL) and it deletes the oldest files when the total DB size exceeds pre-configured values.

FIFO compaction style is suited for storing high-frequency event logs.

Test Plan: Added a unit test

Reviewers: dhruba, haobo, sdong

Reviewed By: dhruba

Subscribers: alberts, leveldb

Differential Revision: https://reviews.facebook.net/D18765
2014-05-21 11:43:35 -07:00
Yueh-Hsuan Chiang
1c7799d8aa Fixed a file-not-found issue when a log file is moved to archive.
Summary:
Fixed a file-not-found issue when a log file is moved to archive
by doing a missing retry.

Test Plan:
make db_test
export ROCKSDB_TEST=TransactionLogIteratorRace
./db_test

Reviewers: sdong, haobo

Reviewed By: sdong

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D18669
2014-05-12 17:50:21 -07:00
sdong
9efbd85ac9 fsync directory after creating current file in NewDB()
Summary: One of our users reported current file corruption. The machine was rebooted during the time. This is the only think I can think of which could cause current file corruption. Just add this paranoid check.

Test Plan: make all check

Reviewers: haobo, igor

Reviewed By: haobo

CC: yhchiang, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D18495
2014-05-06 17:51:33 -07:00
Igor Canadi
16f1aa7b2d Fix signed/unsigned compare 2014-04-30 14:38:01 -04:00
Igor Canadi
df70047669 Flush stale column families
Summary:
Added a new option `max_total_wal_size`. Once the total WAL size goes over that, we make an attempt to flush all column families that still have data in the earliest WAL file.

By default, I calculate `max_total_wal_size` dynamically, that should be good-enough for non-advanced customers.

Test Plan: Added a test

Reviewers: dhruba, haobo, sdong, ljin, yhchiang

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18345
2014-04-30 14:33:40 -04:00
Yueh-Hsuan Chiang
9d9d2965cb Add a new mem-table representation based on cuckoo hash.
Summary:
= Major Changes =
* Add a new mem-table representation, HashCuckooRep, which is based cuckoo hash.
  Cuckoo hash uses multiple hash functions.  This allows each key to have multiple
  possible locations in the mem-table.

  - Put: When insert a key, it will try to find whether one of its possible
    locations is vacant and store the key.  If none of its possible
    locations are available, then it will kick out a victim key and
    store at that location.  The kicked-out victim key will then be
    stored at a vacant space of its possible locations or kick-out
    another victim.  In this diff, the kick-out path (known as
    cuckoo-path) is found using BFS, which guarantees to be the shortest.

 - Get: Simply tries all possible locations of a key --- this guarantees
   worst-case constant time complexity.

 - Time complexity: O(1) for Get, and average O(1) for Put if the
   fullness of the mem-table is below 80%.

 - Default using two hash functions, the number of hash functions used
   by the cuckoo-hash may dynamically increase if it fails to find a
   short-enough kick-out path.

 - Currently, HashCuckooRep does not support iteration and snapshots,
   as our current main purpose of this is to optimize point access.

= Minor Changes =
* Add IsSnapshotSupported() to DB to indicate whether the current DB
  supports snapshots.  If it returns false, then DB::GetSnapshot() will
  always return nullptr.

Test Plan:
Run existing tests.  Will develop a test specifically for cuckoo hash in
the next diff.

Reviewers: sdong, haobo

Reviewed By: sdong

CC: leveldb, dhruba, igor

Differential Revision: https://reviews.facebook.net/D16155
2014-04-29 17:13:46 -07:00
Igor Canadi
dd9eb7a7d5 Cache result of ReadFirstRecord()
Summary:
ReadFirstRecord() reads the actual log file from disk on every call. This diff introduces a cache layer on top of ReadFirstRecord(), which should significantly speed up repeated calls to GetUpdatesSince().

I also cleaned up some stuff, but the whole TransactionLogIterator could use some refactoring, especially if we see increased usage.

Test Plan: make check

Reviewers: haobo, sdong, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18387
2014-04-29 13:27:58 -04:00
Lei Jin
3995e801ab kill ReadOptions.prefix and .prefix_seek
Summary:
also add an override option total_order_iteration if you want to use full
iterator with prefix_extractor

Test Plan: make all check

Reviewers: igor, haobo, sdong, yhchiang

Reviewed By: haobo

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D17805
2014-04-25 12:21:34 -07:00