Commit Graph

826 Commits

Author SHA1 Message Date
Igor Canadi
a96fcd09b7 Deprecate CompactionFilterV2
Summary: It has been around for a while and it looks like it never found any uses in the wild. It's also complicating our compaction_job code quite a bit. We're deprecating it in 3.13, but will put it back in 3.14 if we actually find users that need this feature.

Test Plan: make check

Reviewers: noetzli, yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42405
2015-07-17 18:59:11 +02:00
Siying Dong
d730c36777 Merge pull request #657 from yuslepukhin/ensure_clean_public_headers
Ensure Windows build w/o port/port.h in public headers
2015-07-16 17:47:30 -07:00
Dmitri Smirnov
d1a457181d Ensure Windows build w/o port/port.h in public headers
- Remove make file defines from public headers and use _WIN32 because it is compiler defined
 - use __GNUC__ and __clang__ to guard non-portable attributes
 - add #include "port/port.h" to some new .cc files.
 - minor changes in CMakeLists to reflect recent changes
2015-07-16 12:10:16 -07:00
agiardullo
43e9825625 Fix mongo build -take 2
Summary: quick fix for now.  will figure out a better fix soon

Test Plan: build

Reviewers: sdong, igor, kradhakrishnan

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42381
2015-07-15 18:24:02 -07:00
agiardullo
d8263d9584 Unbreak mongo build
Summary: Unbreak build for mongo.  later, we'll have to figure out if there is a platform independent way to implement ROCKSDB_WARNING

Test Plan: build

Reviewers: igor, sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42369
2015-07-15 17:56:37 -07:00
Igor Canadi
12c5528a89 Bump to RocksDB 3.13
Summary: master is now 3.13-to-be. I'm testing some internal stuff that has #ifdef based on RocksDB version.

Test Plan: none

Reviewers: sdong, anthony

Reviewed By: anthony

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42249
2015-07-15 16:03:20 -07:00
agiardullo
81d072623c move convenience.h out of utilities
Summary: Moved convenience.h out of utilities to remove a dependency on utilities in db.

Test Plan: unit tests.  Also compiled a link to the old location to verify the _Pragma works.

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42201
2015-07-15 14:51:51 -07:00
Igor Canadi
8a9fca2619 Better error handling in BackupEngine
Summary:
Couple of changes here:
* NewBackupEngine() and NewReadOnlyBackupEngine() are now removed. They were deprecated since RocksDB 3.8. Changing these to new functions should be pretty straight-forward. As a followup, I'll fix all fbcode callsights
* Instead of initializing backup engine in the constructor, we initialize it in a separate function now. That way, we can catch all errors and return appropriate status code.
* We catch all errors during initializations and return them to the client properly.
* Added new tests to backupable_db_test, to make sure that we can't open BackupEngine when there are Env errors.
* Transitioned backupable_db_test to use BackupEngine rather than BackupableDB. From the two available APIs, judging by the current use-cases, it looks like BackupEngine API won. It's much more flexible since it doesn't require StackableDB.

Test Plan: Added a new unit test to backupable_db_test

Reviewers: yhchiang, sdong, AaronFeldman

Reviewed By: AaronFeldman

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D41925
2015-07-14 20:51:36 +02:00
Igor Canadi
a9c5109515 Deprecate purge_redundant_kvs_while_flush
Summary: This option is guarding the feature implemented 2 and a half years ago: D8991. The feature was enabled by default back then and has been running without issues. There is no reason why any client would turn this feature off. I found no reference in fbcode.

Test Plan: none

Reviewers: sdong, yhchiang, anthony, dhruba

Reviewed By: dhruba

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D42063
2015-07-14 13:07:02 +02:00
Igor Canadi
5aea98ddd8 Deprecate WriteOptions::timeout_hint_us
Summary:
In one of our recent meetings, we discussed deprecating features that are not being actively used. One of those features, at least within Facebook, is timeout_hint. The feature is really nicely implemented, but if nobody needs it, we should remove it from our code-base (until we get a valid use-case). Some arguments:
* Less code == better icache hit rate, smaller builds, simpler code
* The motivation for adding timeout_hint_us was to work-around RocksDB's stall issue. However, we're currently addressing the stall issue itself (see @sdong's recent work on stall write_rate), so we should never see sharp lock-ups in the future.
* Nobody is using the feature within Facebook's code-base. Googling for `timeout_hint_us` also doesn't yield any users.

Test Plan: make check

Reviewers: anthony, kradhakrishnan, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: sdong, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D41937
2015-07-14 09:35:48 +02:00
Ari Ekmekji
8bca83e5dd Add tombstone information in CompactionJobStats
Summary:
Added new statistics in CompactionJobStats to keep track of
deletion entries and the expiration of those entries. Updated these
fields in compaction_job.cc as compaction took place and wrote a new
test in compaction_job_stats_test.cc to verify accuracy.

Test Plan:
Wrote new test DeletionStatsTest in
compaction_job_stats_test.cc to verify

Reviewers: sdong, igor, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D41355
2015-07-13 15:51:38 -07:00
sdong
f9728640f3 "make format" against last 10 commits
Summary: This helps Windows port to format their changes, as discussed. Might have formatted some other codes too becasue last 10 commits include more.

Test Plan: Build it.

Reviewers: anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D41961
2015-07-13 13:50:18 -07:00
sdong
76d3cd3286 Fix public API dependency on internal codes and dependency on MAX_INT32
Summary:
Public API depends on port/port.h which is wrong. Fix it.
Also with gcc 4.8.1 build was broken as MAX_INT32 was not recognized. Fix it by using ::max in linux.

Test Plan: Build it and try to build an external project on top of it.

Reviewers: anthony, yhchiang, kradhakrishnan, igor

Reviewed By: igor

Subscribers: yoshinorim, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D41745
2015-07-11 10:32:11 -07:00
sdong
a6e38fd170 Fix a uncleaned counter in PerfContext::Reset()
Summary:
new_table_iterator_nanos is not cleaned in PerfContext::Reset() while new_table_block_iter_nanos is cleaned twice. Fix it.
Also fix a comment.

Test Plan: Build and db_bench with --perf_context to see the value shown.

Reviewers: kradhakrishnan, anthony, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D41721
2015-07-10 16:27:32 -07:00
Siying Dong
e41cbd9c2f Merge pull request #646 from yuslepukhin/ms_win_port
Windows Port from Microsoft
2015-07-10 15:53:39 -07:00
Dmitri Smirnov
296de4ae6d Address review comments
Rule of five: add destructor
 Add a note to COMMIT.md for 3rd party json.
2015-07-10 15:21:04 -07:00
sdong
041b6f95a2 perf_context: report time spent on reading index and bloom blocks
Summary: Add a perf context counter to help users figure out time spent on reading indexes and bloom filter blocks.

Test Plan: Will write a unit test

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D41433
2015-07-10 14:45:42 -07:00
Dmitri Smirnov
c903ccc4c2 Merge from github/master 2015-07-09 18:01:08 -07:00
unknown
5c79132335 Revert the changes related to Options, as requested to seperate them into
a different patch.
2015-07-09 11:31:42 -07:00
Dmitri Smirnov
ef4b87f1b2 Commit both PR and internal code review changes 2015-07-07 16:58:20 -07:00
Poornima Chozhiyath Raman
c0b23dd5b0 Enabling trivial move in universal compaction
Summary: This change enables trivial move if all the input files are non onverlapping while doing Universal Compaction.

Test Plan: ./compaction_picker_test and db_test ran successfully with the new testcases.

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D40875
2015-07-07 14:18:55 -07:00
Dmitri Smirnov
d2f0912bd3 Merge the latest changes from github/master 2015-07-02 17:23:41 -07:00
Ari Ekmekji
35cd75c379 Introduce InfoLogLevel::HEADER_LEVEL
Summary:
 Introduced a new category in the enum InfoLogLevel in env.h.
 Modifed Log() in env.cc to use the Header()
 when the InfoLogLevel == HEADER_LEVEL.
 Updated tests in auto_roll_logger_test to ensure
 the header is handled properly in these cases.

Test Plan: Augment existing tests in auto_roll_logger_test

Reviewers: igor, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D41067
2015-07-02 17:14:39 -07:00
Dmitri Smirnov
feb99c31a4 Merge remote-tracking branch 'origin' into ms_win_port 2015-07-02 13:14:18 -07:00
agiardullo
4159f5b87b Prepare 3.12
Summary: About to cut release

Test Plan: none

Reviewers: igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D41061
2015-07-02 12:20:36 -07:00
Aaron Feldman
a69bc91e37 Multithreaded backup and restore in BackupEngineImpl
Summary:
Add a new field: BackupableDBOptions.max_background_copies.
CreateNewBackup() and RestoreDBFromBackup() will use this number of threads to perform copies.
If there is a backup rate limit, then max_background_copies must be 1.
Update backupable_db_test.cc to test multi-threaded backup and restore.
Update backupable_db_test.cc to test backups when the backup environment is not the same as the database environment.

Test Plan:
Run ./backupable_db_test
Run valgrind ./backupable_db_test
Run with TSAN and ASAN

Reviewers: yhchiang, rven, anthony, sdong, igor

Reviewed By: igor

Subscribers: yhchiang, anthony, sdong, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D40725
2015-07-02 11:35:51 -07:00
Dmitri Smirnov
9dbde7277c Merge remote-tracking branch 'origin' into ms_win_port 2015-07-02 11:34:22 -07:00
Dmitri Smirnov
ca2fe2c1b6 Address GCC compilation issues
invalid suffix on literal
 no return statement in function returning non-void CuckooStep::operator=
 extra qualification ‘rocksdb::spatial::Variant::
 dereferencing type-punned pointer will break strict-aliasing rules
2015-07-01 17:04:08 -07:00
Dmitri Smirnov
18285c1e2f Windows Port from Microsoft
Summary: Make RocksDb build and run on Windows to be functionally
 complete and performant. All existing test cases run with no
 regressions. Performance numbers are in the pull-request.

 Test plan: make all of the existing unit tests pass, obtain perf numbers.

 Co-authored-by: Praveen Rao praveensinghrao@outlook.com
 Co-authored-by: Sherlock Huang baihan.huang@gmail.com
 Co-authored-by: Alex Zinoviev alexander.zinoviev@me.com
 Co-authored-by: Dmitri Smirnov dmitrism@microsoft.com
2015-07-01 16:13:56 -07:00
Igor Canadi
4cbc4e6f88 Call merge operators with empty values
Summary: It's not really nice to call user's API with garbage data in new_value. This diff makes sure that new_value is empty before calling the merge operator.

Test Plan: Added assert to Merge operator in merge_test

Reviewers: sdong, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D40773
2015-06-26 11:35:46 -07:00
Yueh-Hsuan Chiang
48da7a9cad Improve the comment for BYTES_READ in statistics.
Summary:
BYTES_READ only count the number of logical bytes read from
the DB::Get() function.  It neither includes all logical bytes read
nor indicates IO read bytes.

This patch improves the comment for BYTES_READ.

Test Plan: Only change comment.

Reviewers: sdong, rven, anthony, kradhakrishnan, IslamAbdelRahman, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D40599
2015-06-24 15:00:51 -07:00
Islam AbdelRahman
674b1181cf Bottommost level compaction option
Summary: Replace force_bottommost_level_compaction in CompactRangeOption with an option that allow the user to (always skip, always compact, compact if compaction filter is present) the bottommost level for level based compaction.

Test Plan: make check

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D40527
2015-06-23 13:32:40 -07:00
Giuseppe Ottaviano
782a1590f9 Implement a table-level row cache
Summary:
Implementation of a table-level row cache.
It only caches point queries done through the `DB::Get` interface, queries done through the `Iterator` interface will completely skip the cache.

Supports snapshots and merge operations.

Test Plan: Ran `make valgrind_check commit-prereq`

Reviewers: igor, philipp, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39849
2015-06-23 10:25:45 -07:00
krad
de85e4cadf Introduce WAL recovery consistency levels
Summary:
The "one size fits all" approach with WAL recovery will only introduce inconvenience for our varied clients as we go forward. The current recovery is a bit heuristic. We introduce the following levels of consistency while replaying the WAL.

1. RecoverAfterRestart (kTolerateCorruptedTailRecords)

This mocks the current recovery mode.

2. RecoverAfterCleanShutdown (kAbsoluteConsistency)

This is ideal for unit test and cases where the store is shutdown cleanly. We tolerate no corruption or incomplete writes.

3. RecoverPointInTime (kPointInTimeRecovery)

This is ideal when using devices with controller cache or file systems which can loose data on restart. We recover upto the point were is no corruption or incomplete write.

4. RecoverAfterDisaster (kSkipAnyCorruptRecord)

This is ideal mode to recover data. We tolerate corruption and incomplete writes, and we hop over those sections that we cannot make sense of salvaging as many records as possible.

Test Plan:
(1) Run added unit test to cover all levels.
(2) Run make check.

Reviewers: leveldb, sdong, igor

Subscribers: yoshinorim, dhruba

Differential Revision: https://reviews.facebook.net/D38487
2015-06-22 15:28:12 -07:00
krad
7015fd81c4 Add read_nanos to IOStatsContext.
Summary: MyRocks need a mechanism to track read outliers. We need to expose this
stat.

Test Plan: None

Reviewers: sdong

CC: leveldb

Task ID: #7152512

Blame Rev:
2015-06-22 11:09:35 -07:00
Yueh-Hsuan Chiang
eade498bda Block utilities/write_batch_with_index in ROCKSDB_LITE
Summary:
Block utilities/write_batch_with_index in ROCKSDB_LITE as we
don't include anly utilities in ROCKSDB_LITE

Test Plan: write_batch_with_index_test

Reviewers: rven, anthony, kradhakrishnan, IslamAbdelRahman, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D40347
2015-06-18 15:54:05 -07:00
Igor Canadi
760e9a94de Fail DB::Open() when the requested compression is not available
Summary:
Currently RocksDB silently ignores this issue and doesn't compress the data. Based on discussion, we agree that this is pretty bad because it can cause confusion for our users.

This patch fails DB::Open() if we don't support the compression that is specified in the options.

Test Plan: make check with LZ4 not present. If Snappy is not present all tests will just fail because Snappy is our default library. We should make Snappy the requirement, since without it our default DB::Open() fails.

Reviewers: sdong, MarkCallaghan, rven, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39687
2015-06-18 14:55:05 -07:00
Aaron Feldman
69bb210d58 Add Cache.GetPinnedUsageUsage()
Summary:
  Add the funcion Cache.GetPinnedUsage() to return the memory size of entries
  that are in use by the system (that is, all the entries not in the LRU list).

Test Plan:
  Run ./cache_test and examine PinnedUsageTest.

Reviewers: tnovak, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D40305
2015-06-18 13:56:31 -07:00
Islam AbdelRahman
4eabbdb7ec Skip bottommost level compaction if possible
Summary:
This is https://reviews.facebook.net/D39999 but after introducing an option to force compaction the bottom most level

Changes in this patch
- Introduce force_bottommost_level_compaction to CompactRangeOptions that force compacting bottommost level during compaction
- Skip bottommost level compaction if we dont have a compaction filter and force_bottommost_level_compaction options is not set

Although tests pass on my machine but I suspect that there maybe some tests that I am not aware of that  should use force_bottommost_level_compaction to pass in a deterministic way

Test Plan:
make check
adding new tests

Reviewers: igor, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D40059
2015-06-18 11:03:31 -07:00
Igor Canadi
4b8bb62f0a Don't dump DBOptions for each column family
Summary: Currently we dump DBOptions for each column family options we dump. This leads to duplicate lines in our LOG file. This diff fixes that.

Test Plan: Check out the LOG

Reviewers: sdong, rven, yhchiang

Reviewed By: yhchiang

Subscribers: IslamAbdelRahman, yoshinorim, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39729
2015-06-18 10:15:54 -07:00
Islam AbdelRahman
12e030a992 Use CompactRangeOptions for CompactRange
Summary:
This diff update DB::CompactRange to use RangeCompactionOptions instead of using multiple parameters
Old CompactRange is still available but deprecated

Test Plan:
make all check
make rocksdbjava
USE_CLANG=1 make all
OPT=-DROCKSDB_LITE make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D40209
2015-06-17 14:36:14 -07:00
Holodov Alexander
84a9c6a53a add comment 2015-05-16 15:29:39 +04:00
Holodov Alexander
eeb44366ba C api: human-readable statistics 2015-05-16 12:34:28 +04:00
sdong
40f562e747 Allow GetApproximateSize() to include mem table size if it is skip list memtable
Summary:
Add an option in GetApproximateSize() so that the result will include estimated sizes in mem tables.
To implement it, implement an estimated count from the beginning to a key in skip list. The approach is to count to find the entry, how many Next() is issued from each level, and sum them with a weight that is <branching factor> ^ <level>.

Test Plan: Add a test case

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D40119
2015-06-16 18:13:23 -07:00
sdong
7842920be5 Slow down writes by bytes written
Summary:
We slow down data into the database to the rate of options.delayed_write_rate (a new option) with this patch.

The thread synchronization approach I take is to still synchronize write controller by DB mutex and GetDelay() is inside DB mutex. Try to minimize the frequency of getting time in GetDelay(). I verified it through db_bench and it seems to work

hard_rate_limit is deprecated.

options.delayed_write_rate is still not dynamically changeable. Need to work on it as a follow-up.

Test Plan: Add new unit tests in db_test

Reviewers: yhchiang, rven, kradhakrishnan, anthony, MarkCallaghan, igor

Reviewed By: igor

Subscribers: ikabiljo, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D36351
2015-06-11 20:42:18 -07:00
Islam AbdelRahman
d6ce0f7c61 Add largest sequence to FlushJobInfo
Summary:
Adding largest sequence number to FlushJobInfo
and passing flushed file metadata to NotifyOnFlushCompleted which include alot of other values that we may want to expose in FlushJobInfo

Test Plan: make check

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39927
2015-06-11 15:22:22 -07:00
Yueh-Hsuan Chiang
3eddd1abe9 Add Env::GetThreadID(), which returns the ID of the current thread.
Summary:
Add Env::GetThreadID(), which returns the ID of the current thread.

In addition, make GetThreadList() and InfoLog use same unique ID for the same thread.

Test Plan:
db_test
listener_test

Reviewers: igor, rven, IslamAbdelRahman, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39735
2015-06-11 14:18:02 -07:00
Igor Canadi
821cff114e Re-generate WriteEntry on WBWIIterator::Entry()
Summary:
[This is the resubmit of D39813. Tests were failing, so I reverted the diff. I found the bug and I'm now resubmitting]

If we don't do this, any calls to Entry() after WBWI mutation will result in undefined behavior. We need to re-fetch the offset from the skip list and regenerate the new pointer (because string's base pointer can change while mutating).

Test Plan: COMPILE_WITH_ASAN=1 make write_batch_with_index_test && ./write_batch_with_index_test

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39897
2015-06-10 12:57:38 -07:00
Igor Canadi
75222d130e Revert "Fix compile"
This reverts commit 51440f83ec.

Revert "Re-generate WriteEntry on WBWIIterator::Entry()"

This reverts commit 4949ef08db.
2015-06-10 11:05:27 -07:00
Igor Canadi
47f1e72125 Merge pull request #630 from rdallman/c-wb-logdata
C: add WriteBatch.PutLogData support
2015-06-10 10:50:28 -07:00
Igor Canadi
4949ef08db Re-generate WriteEntry on WBWIIterator::Entry()
Summary: If we don't do this, any calls to Entry() after WBWI mutation will result in undefined behavior. We need to re-fetch the offset from the skip list and regenerate the new pointer (because string's base pointer can change while mutating).

Test Plan: COMPILE_WITH_ASAN=1 make write_batch_with_index_test && ./write_batch_with_index_test

Reviewers: sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39813
2015-06-10 10:35:19 -07:00
Reed Allman
735df66552 C: add WriteBatch.PutLogData support 2015-06-10 00:12:33 -07:00
Islam AbdelRahman
643bbbf081 Use nullptr for default compaction_filter_factory
Summary:
Replacing the default value for compaction_filter_factory and compaction_filter_factory_v2 to be nullptr instead of DefaultCompactionFilterFactory / DefaultCompactionFilterFactoryV2
The reason for this is to be able to determine easily if we have compaction filter factory or not without depending on RTTI

Test Plan: make check

Reviewers: yoshinorim, ott, igor, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D39693
2015-06-08 16:34:26 -07:00
Igor Canadi
133130a4f5 Merge pull request #625 from rdallman/c-slice-parts-support
C: add support for WriteBatch SliceParts params
2015-06-08 13:14:44 -04:00
Igor Canadi
de4d172d0f Merge pull request #622 from rdallman/c-multiget
C: add MultiGet support
2015-06-08 13:13:54 -04:00
sdong
6df589b446 Add TablePropertiesCollector::NeedCompact() to suggest DB to further compact output files
Summary:
It is experimental. Allow users to return from a call back function TablePropertiesCollector::NeedCompact(), based on the data in the file.
It can be used to allow users to suggest DB to clear up delete tombstones faster.

Test Plan: Add a unit test.

Reviewers: igor, yhchiang, kradhakrishnan, rven

Reviewed By: rven

Subscribers: yoshinorim, MarkCallaghan, maykov, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39585
2015-06-05 20:18:21 -07:00
Yueh-Hsuan Chiang
2e764f06ea [API Change] Improve EventListener::OnFlushCompleted interface
Summary:
EventListener::OnFlushCompleted() now passes a structure instead
of a list of parameters.  This minimizes the API change in the
future.

Test Plan:
listener_test
compact_files_test
example/compact_files_example

Reviewers: kradhakrishnan, sdong, IslamAbdelRahman, rven, igor

Reviewed By: rven, igor

Subscribers: IslamAbdelRahman, rven, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39543
2015-06-05 12:28:51 -07:00
Yueh-Hsuan Chiang
bb808eaddb Changed the CompactionJobStats::output_key_prefix type from char[] to string.
Summary:
Keys in RocksDB can be arbitrary byte strings.  However, in the current
CompactionJobStats, smallest_output_key_prefix and largest_output_key_prefix
are of type char[] without having a length, which is insufficient to handle
non-null terminated strings.

This patch change their type to std::string.

Test Plan: compaction_job_stats_test

Reviewers: igor, rven, IslamAbdelRahman, kradhakrishnan, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39537
2015-06-04 12:31:12 -07:00
Yueh-Hsuan Chiang
0b3172d071 Add EventListener::OnTableFileDeletion()
Summary:
Add EventListener::OnTableFileDeletion(), which will be
called when a table file is deleted.

Test Plan: Extend three existing tests in db_test to verify the deleted files.

Reviewers: rven, anthony, kradhakrishnan, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38931
2015-06-03 19:57:01 -07:00
Reed Allman
211a195d41 C: add MultiGet support 2015-06-03 17:57:42 -07:00
Reed Allman
5dc174e11a C: add support for WriteBatch SliceParts params 2015-06-03 17:08:00 -07:00
Igor Canadi
408cc4b8e0 Revert "Merge pull request #621 from rdallman/c-slice-parts-support"
This reverts commit 78382d4ba7, reversing
changes made to ca8b85ac04.
2015-06-03 13:34:07 -04:00
Igor Canadi
78382d4ba7 Merge pull request #621 from rdallman/c-slice-parts-support
C: add support for WriteBatch SliceParts params
2015-06-03 13:16:14 -04:00
agiardullo
ca8b85ac04 better document max_write_buffer_number_to_maintain
Test Plan: compile

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39285
2015-06-02 21:24:19 -07:00
Yueh-Hsuan Chiang
fe5c6321cb Allow EventListener::OnCompactionCompleted to return CompactionJobStats.
Summary:
Allow EventListener::OnCompactionCompleted to return CompactionJobStats,
which contains useful information about a compaction.

Example CompactionJobStats returned by OnCompactionCompleted():
    smallest_output_key_prefix 05000000
    largest_output_key_prefix 06990000
    elapsed_time 42419
    num_input_records 300
    num_input_files 3
    num_input_files_at_output_level 2
    num_output_records 200
    num_output_files 1
    actual_bytes_input 167200
    actual_bytes_output 110688
    total_input_raw_key_bytes 5400
    total_input_raw_value_bytes 300000
    num_records_replaced 100
    is_manual_compaction 1

Test Plan: Developed a mega test in db_test which covers 20 variables in CompactionJobStats.

Reviewers: rven, igor, anthony, sdong

Reviewed By: sdong

Subscribers: tnovak, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38463
2015-06-02 17:07:16 -07:00
Yueh-Hsuan Chiang
8d8d4e45ba Fixed ROCKSDB_LITE compile error due to the missing of TableFileCreationInfo
Summary: Fixed ROCKSDB_LITE compile error due to the missing of TableFileCreationInfo

Test Plan: make OPT=-DROCKSDB_LITE shared_lib -j32

Reviewers: sdong, igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39405
2015-06-02 14:27:46 -07:00
Yueh-Hsuan Chiang
fc83821270 Add EventListener::OnTableFileCreated()
Summary:
Add EventListener::OnTableFileCreated(), which will be called
when a table file is created.  This patch is part of the
EventLogger and EventListener integration.

Test Plan: Augment existing test in db/listener_test.cc

Reviewers: anthony, kradhakrishnan, rven, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38865
2015-06-02 14:12:23 -07:00
sdong
ac81130fa0 Fix Bug: CompactRange() doesn't change to correct level caused by using wrong level
Summary: In previous change https://reviews.facebook.net/D39099 , while renaming parameters, use a wrong parameter, causing CompactRange() to compact not wrong level.

Test Plan: Run "DBTest.MigrateToDynamicLevelMaxBytesBase" which failed with the patch.

Reviewers: rven, yhchiang, kradhakrishnan, igor, anthony

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39393
2015-06-02 10:00:58 -07:00
Mike Kolupaev
ec7a944360 more times in perf_context and iostats_context
Summary:
We occasionally get write stalls (>1s Write() calls) on HDD under read load. The following timers explain almost all of the stalls:
 - perf_context.db_mutex_lock_nanos
 - perf_context.db_condition_wait_nanos
 - iostats_context.open_time
 - iostats_context.allocate_time
 - iostats_context.write_time
 - iostats_context.range_sync_time
 - iostats_context.logger_time

In my experiments each of these occasionally takes >1s on write path under some workload. There are rare cases when Write() takes long but none of these takes long.

Test Plan: Added code to our application to write the listed timings to log for slow writes. They usually add up to almost exactly the time Write() call took.

Reviewers: rven, yhchiang, sdong

Reviewed By: sdong

Subscribers: march, dhruba, tnovak

Differential Revision: https://reviews.facebook.net/D39177
2015-06-02 02:07:58 -07:00
sdong
4266d4fd90 Allow users to migrate to options.level_compaction_dynamic_level_bytes=true using CompactRange()
Summary: In DB::CompactRange(), change parameter "reduce_level" to "change_level". Users can compact all data to the last level if needed. By doing it, users can migrate the DB to options.level_compaction_dynamic_level_bytes=true.

Test Plan: Add a unit test for it.

Reviewers: yhchiang, anthony, kradhakrishnan, igor, rven

Reviewed By: rven

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D39099
2015-06-01 18:21:14 -07:00
Mike Kolupaev
2ecac9f96d add rocksdb::WritableFileWrapper similar to rocksdb::EnvWrapper
Summary: It used to be no good (known to me) non-intrusive way to wrap WritableFile - you can't call protected virtual methods of the wrapped pointer to WritableFile. This diff adds a convenience class WritableFileWrapper that makes wrapping WritableFile both possible and easy.

Test Plan: `make clean; make -j release`, `make clean; OPT=-DROCKSDB_LITE make release`, `make clean; USE_CLANG=1 make -j all`.

Reviewers: sdong, yhchiang, rven

Reviewed By: rven

Subscribers: dhruba, tnovak, march

Differential Revision: https://reviews.facebook.net/D39147
2015-06-01 11:22:36 -07:00
Igor Canadi
a187e66ad0 Merge pull request #617 from rdallman/wb-merge-sliceparts
WriteBatch.Merge w/ SliceParts support
2015-05-31 13:34:34 -04:00
agiardullo
dc9d70de65 Optimistic Transactions
Summary: Optimistic transactions supporting begin/commit/rollback semantics.  Currently relies on checking the memtable to determine if there are any collisions at commit time.  Not yet implemented would be a way of enuring the memtable has some minimum amount of history so that we won't fail to commit when the memtable is empty.  You should probably start with transaction.h to get an overview of what is currently supported.

Test Plan: Added a new test, but still need to look into stress testing.

Reviewers: yhchiang, igor, rven, sdong

Reviewed By: sdong

Subscribers: adamretter, MarkCallaghan, leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D33435
2015-05-29 14:36:35 -07:00
Yueh-Hsuan Chiang
ebfdb3c7f6 Fixed a compile error in ROCKSDB_LITE
Summary: Fixed a compile error in ROCKSDB_LITE

Test Plan: make db_stress OPT=-DROCKSDB_LITE -j32

Reviewers: sdong, igor, anthony

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39201
2015-05-29 13:21:09 -07:00
Yueh-Hsuan Chiang
9ffc8ba024 Include EventListener in stress test.
Summary: Include EventListener in stress test.

Test Plan: make blackbox_crash_test whitebox_crash_test

Reviewers: anthony, igor, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39105
2015-05-29 13:17:49 -07:00
Reed Allman
21cd6b7ad8 C: add support for WriteBatch SliceParts params 2015-05-29 10:23:43 -07:00
Reed Allman
a0635ba3f6 WriteBatch.Merge w/ SliceParts support
also hooked up WriteBatchInternal
2015-05-29 04:30:03 -07:00
agiardullo
c815351038 Support saving history in memtable_list
Summary:
For transactions, we are using the memtables to validate that there are no write conflicts.  But after flushing, we don't have any memtables, and transactions could fail to commit.  So we want to someone keep around some extra history to use for conflict checking.  In addition, we want to provide a way to increase the size of this history if too many transactions fail to commit.

After chatting with people, it seems like everyone prefers just using Memtables to store this history (instead of a separate history structure).  It seems like the best place for this is abstracted inside the memtable_list.  I decide to create a separate list in MemtableListVersion as using the same list complicated the flush/installalflushresults logic too much.

This diff adds a new parameter to control how much memtable history to keep around after flushing.  However, it sounds like people aren't too fond of adding new parameters.  So I am making the default size of flushed+not-flushed memtables be set to max_write_buffers.  This should not change the maximum amount of memory used, but make it more likely we're using closer the the limit.  (We are now postponing deleting flushed memtables until the max_write_buffer limit is reached).  So while we might use more memory on average, we are still obeying the limit set (and you could argue it's better to go ahead and use up memory now instead of waiting for a write stall to happen to test this limit).

However, if people are opposed to this default behavior, we can easily set it to 0 and require this parameter be set in order to use transactions.

Test Plan: Added a xfunc test to play around with setting different values of this parameter in all tests.  Added testing in memtablelist_test and planning on adding more testing here.

Reviewers: sdong, rven, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D37443
2015-05-28 16:34:24 -07:00
Yueh-Hsuan Chiang
672dda9b3b [API Change] Move listeners from ColumnFamilyOptions to DBOptions
Summary: Move listeners from ColumnFamilyOptions to DBOptions

Test Plan:
listener_test
compact_files_test

Reviewers: rven, anthony, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D39087
2015-05-28 13:21:39 -07:00
Reed Allman
9c38ce1d02 C: extra bbto / noop slice transform 2015-05-22 22:56:28 -07:00
Igor Canadi
4cb4d546cd Set stats_dump_period_sec to 600 by default
Summary: Having stats in our LOG more often will help a lot with perf debugging.

Test Plan: none

Reviewers: sdong, MarkCallaghan

Reviewed By: MarkCallaghan

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38781
2015-05-21 14:22:16 -04:00
Yueh-Hsuan Chiang
e2c1d4b57f [Public API Change] Make DB::GetDbIdentity() be const function.
Summary: Make DB::GetDbIdentity() be const function.

Test Plan: make db_test

Reviewers: igor, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38745
2015-05-21 11:01:48 -07:00
Igor Canadi
4a855c0799 Add an option wal_bytes_per_sync to control sync_file_range for WAL files
Summary:
sync_file_range is not always asyncronous and thus can block writes if we do this for WAL in the foreground thread. See more here: http://yoshinorimatsunobu.blogspot.com/2014/03/how-syncfilerange-really-works.html

Some users don't want us to call sync_file_range on WALs. Some other do.
Thus, I'm adding a separate option wal_bytes_per_sync to control calling
sync_file_range on WAL files. bytes_per_sync will apply only to table
files now.

Test Plan: no more sync_file_range for WAL as evidenced by strace

Reviewers: yhchiang, rven, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38253
2015-05-18 17:03:59 -07:00
sdong
6fa7085121 CompactRange skips levels 1 to base_level -1 for dynamic level base size
Summary: CompactRange() now is much more expensive for dynamic level base size as it goes through all the levels. Skip those not used levels between level 0 an base level.

Test Plan: Run all unit tests

Reviewers: yhchiang, rven, anthony, kradhakrishnan, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D37125
2015-05-18 10:54:11 -07:00
Yueh-Hsuan Chiang
3f0867c0fe Allow GetThreadList to report Flush properties.
Summary:
Allow GetThreadList to report Flush properties, which includes:
* job id
* number of bytes that has been written since flush started.
* total size of input mem-tables

Test Plan:
./db_bench --threads=30 --num=1000000 --benchmarks=fillrandom --thread_status_per_interval=100 --value_size=1000

Sample output from db_bench which tracks same flush job

          ThreadID ThreadType       cfName            Operation   ElapsedTime                                         Stage        State OperationProperties
   140213879898240   High Pri      default                Flush       5789 us                    FlushJob::WriteLevel0Table              BytesMemtables 4112835 | BytesWritten 577104 | JobID 8 |

          ThreadID ThreadType       cfName            Operation   ElapsedTime                                         Stage        State OperationProperties
   140213879898240   High Pri      default                Flush     30.634 ms                    FlushJob::WriteLevel0Table              BytesMemtables 4112835 | BytesWritten 1734865 | JobID 8 |

Reviewers: rven, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38505
2015-05-15 23:22:22 -07:00
Yueh-Hsuan Chiang
a66f643e97 Use a better way to initialize ThreadStatus::kNumOperationProperties.
Summary: Use a better way to initialize ThreadStatus::kNumOperationProperties.

Test Plan: make

Reviewers: sdong, rven, anthony, krishnanm86, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38547
2015-05-15 15:55:20 -07:00
sdong
ec43a8b9fb Universal Compaction with multiple levels won't allocate up to output size
Summary: Universal compactions with multiple levels should use file preallocation size based on file size if output level is not level 0

Test Plan: Run all tests.

Reviewers: igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D38439
2015-05-13 14:15:46 -07:00
Yueh-Hsuan Chiang
714fcc067d Make ThreadStatus::InterpretOperationProperties take const uint64_t*
Summary: Make ThreadStatus::InterpretOperationProperties take const uint64_t*

Test Plan:
make
make OPT=-DROCKSDB_LITE shared_lib

Reviewers: igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38445
2015-05-13 12:26:07 -07:00
Yueh-Hsuan Chiang
14431e971d Fixed a bug in EventListener::OnCompactionCompleted().
Summary:
Fixed a bug in EventListener::OnCompactionCompleted() that returns
incorrect list of input / output file names.

Test Plan: Extend existing test in listener_test.cc

Reviewers: sdong, rven, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38349
2015-05-12 16:10:23 -07:00
agiardullo
711465ccec API to fetch from both a WriteBatchWithIndex and the db
Summary:
Added a couple functions to WriteBatchWithIndex to make it easier to query the value of a key including reading pending writes from a batch.  (This is needed for transactions).

I created write_batch_with_index_internal.h to use to store an internal-only helper function since there wasn't a good place in the existing class hierarchy to store this function (and it didn't seem right to stick this function inside WriteBatchInternal::Rep).

Since I needed to access the WriteBatchEntryComparator, I moved some helper classes from write_batch_with_index.cc into write_batch_with_index_internal.h/.cc.  WriteBatchIndexEntry, ReadableWriteBatch, and WriteBatchEntryComparator are all unchanged (just moved to a different file(s)).

Test Plan: Added new unit tests.

Reviewers: rven, yhchiang, sdong, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38037
2015-05-11 14:51:51 -07:00
Igor Canadi
962f8ba332 Bump to 3.11
Summary: as title

Test Plan: none

Reviewers: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D38175
2015-05-07 13:27:14 -07:00
Yueh-Hsuan Chiang
77a5a543a5 Allow GetThreadList() to report basic compaction operation properties.
Summary:
Now we're able to show more details about a compaction in
GetThreadList() :)

This patch allows GetThreadList() to report basic compaction
operation properties.  Basic compaction properties include:
    1. job id
    2. compaction input / output level
    3. compaction property flags (is_manual, is_deletion, .. etc)
    4. total input bytes
    5. the number of bytes has been read currently.
    6. the number of bytes has been written currently.

Flush operation properties will be done in a seperate diff.

Test Plan:
/db_bench --threads=30 --num=1000000 --benchmarks=fillrandom --thread_status_per_interval=1

Sample output of tracking same job:

          ThreadID ThreadType       cfName            Operation   ElapsedTime                                         Stage        State OperationProperties
   140664171987072    Low Pri      default           Compaction     31.357 ms     CompactionJob::FinishCompactionOutputFile              BaseInputLevel 1 | BytesRead 2264663 | BytesWritten 1934241 | IsDeletion 0 | IsManual 0 | IsTrivialMove 0 | JobID 277 | OutputLevel 2 | TotalInputBytes 3964158 |

          ThreadID ThreadType       cfName            Operation   ElapsedTime                                         Stage        State OperationProperties
   140664171987072    Low Pri      default           Compaction     59.440 ms     CompactionJob::FinishCompactionOutputFile              BaseInputLevel 1 | BytesRead 2264663 | BytesWritten 1934241 | IsDeletion 0 | IsManual 0 | IsTrivialMove 0 | JobID 277 | OutputLevel 2 | TotalInputBytes 3964158 |

          ThreadID ThreadType       cfName            Operation   ElapsedTime                                         Stage        State OperationProperties
   140664171987072    Low Pri      default           Compaction    226.375 ms                        CompactionJob::Install              BaseInputLevel 1 | BytesRead 3958013 | BytesWritten 3621940 | IsDeletion 0 | IsManual 0 | IsTrivialMove 0 | JobID 277 | OutputLevel 2 | TotalInputBytes 3964158 |

Reviewers: sdong, rven, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D37653
2015-05-06 22:51:06 -07:00
Laurent Demailly
df4130ad85 fix crashes in stats and compaction filter for db_ttl_impl
Summary: fix crashes in stats and compaction filter for db_ttl_impl

Test Plan:
Ran build with lots of debugging
https://reviews.facebook.net/differential/diff/194175/

Reviewers: yhchiang, igor, rven

Reviewed By: igor

Subscribers: rven, dhruba

Differential Revision: https://reviews.facebook.net/D38001
2015-05-05 16:54:47 -07:00
Igor Canadi
fd96b55402 Making GetOptions() comment better (#597) 2015-04-30 09:29:51 -07:00
Aashish Pant
794ccfde89 Task 6532943: Rocksdb - SetCapacity() can dynamically change cache capacity if feasible
Summary:
When new capacity is larger than existing capacity, simply update the capacity to the new valie
When new capacity is less than existing capacity, but more than the usage, simply update the capacity to new value
When new capacity is less than the existing capacity and existing usage both, try to purge entries in LRU if feasible to make usage < capacity

Test Plan: Created unit tests in cache_test.cc

Reviewers: sdong, rven, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D37527
2015-04-24 14:12:58 -07:00
sdong
98a44559d5 Build for CYGWIN
Summary:
Make it build for CYGWIN.
Need to define "-std=gnu++11" instead of "-std=c++11" and use some replacement functions.

Test Plan: Build it and run some unit tests in CYGWIN

Reviewers: yhchiang, rven, anthony, kradhakrishnan, igor

Reviewed By: igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D37605
2015-04-23 21:33:44 -07:00
Giuseppe Ottaviano
2dc421df48 Implement DB::PromoteL0 method
Summary:
This diff implements a new `DB` method `PromoteL0` which moves all files in L0
to a given level skipping compaction, provided that the files have disjoint
ranges and all levels up to the target level are empty.

This method provides finer-grain control for trivial compactions, and it is
useful for bulk-loading pre-sorted keys. Compared to D34797, it does not change
the semantics of an existing operation, which can impact existing code.

PromoteL0 is designed to work well in combination with the proposed
`GetSstFileWriter`/`AddFile` interface, enabling to "design" the level structure
by populating one level at a time. Such fine-grained control can be very useful
for static or mostly-static databases.

Test Plan: `make check`

Reviewers: IslamAbdelRahman, philipp, MarkCallaghan, yhchiang, igor, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D37107
2015-04-23 12:10:36 -07:00
sdong
397b6588bd options.paranoid_file_checks to read all rows after writing to a file.
Summary: To further distinguish the corruption cases were caused by storage media or in memory states when writing it, add a paranoid check after writing the file to iterate all the rows.

Test Plan: Add a new unit test for it

Reviewers: rven, igor

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D37335
2015-04-23 11:34:35 -07:00
Igor Canadi
6059bdf86a Add experimental API MarkForCompaction()
Summary:
Some Mongo+Rocks datasets in Parse's environment are not doing compactions very frequently. During the quiet period (with no IO), we'd like to schedule compactions so that our reads become faster. Also, aggressively compacting during quiet periods helps when write bursts happen. In addition, we also want to compact files that are containing deleted key ranges (like old oplog keys).

All of this is currently not possible with CompactRange() because it's single-threaded and blocks all other compactions from happening. Running CompactRange() risks an issue of blocking writes because we generate too much Level 0 files before the compaction is over. Stopping writes is very dangerous because they hold transaction locks. We tried running manual compaction once on Mongo+Rocks and everything fell apart.

MarkForCompaction() solves all of those problems. This is very light-weight manual compaction. It is lower priority than automatic compactions, which means it shouldn't interfere with background process keeping the LSM tree clean. However, if no automatic compactions need to be run (or we have extra background threads available), we will start compacting files that are marked for compaction.

Test Plan: added a new unit test

Reviewers: yhchiang, rven, MarkCallaghan, sdong

Reviewed By: sdong

Subscribers: yoshinorim, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D37083
2015-04-17 16:44:45 -07:00
agiardullo
84c5bd7eb9 Add thread-safety documentation to MemTable and related classes
Summary: Other than making some class members private, this is a documentation-only change

Test Plan: unit tests

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D36567
2015-04-08 21:10:35 -07:00