Commit graph

62 commits

Author SHA1 Message Date
Danny Al-Gaaf 177caca428 ttl/ttl_test.cc: pass const string param by reference
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
2014-10-01 11:53:00 +02:00
Danny Al-Gaaf b140375565 ttl/ttl_test.cc: prefer prefix ++operator for non-primitive types
Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
2014-09-30 23:30:32 +02:00
Danny Al-Gaaf 873f1356a1 db_ttl_impl.h: pass func parameter by reference
Fix for:

[utilities/ttl/db_ttl_impl.h:209]: (performance) Function parameter
 'merge_op' should be passed by reference.

Signed-off-by: Danny Al-Gaaf <danny.al-gaaf@bisect.de>
2014-09-30 23:30:32 +02:00
Igor Canadi 0ff183a0d9 Move include/utilities/*.h to include/rocksdb/utilities/*.h
Summary:
All public headers need to be under `include/rocksdb` directory. Otherwise, clients include our header files like this:

    #include <rocksdb/db.h>
    #include <utilities/backupable_db.h> // still our public header!

Also, internally, we include:

    #include "utilities/backupable/backupable_db.h" // internal header
    #include "utilities/backupable_db.h" // public header

which is confusing.

This way, when we install rocksdb as a system library, we can just copy `include/rocksdb` directory to system's header files. We can't really copy `utilities` directory to system's header files.

Test Plan: compiles

Reviewers: dhruba, ljin, yhchiang, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D20409
2014-07-23 10:21:38 -04:00
Igor Canadi 3b5fa6bd9b Improve ttl_test
Summary:
Our valgrind tests are failing because ttl_test is kind of flakey. This diff should fix valgrind issue and make ttl_test less flakey and much faster.

Instead of relying on Env::Default() for getting current time, I expose `Env*` to all TTL functions that are interested in time. That way, I can insert a custom test Env which is then used to provide exactly the times we need. That way, we don't need to sleep anymore -- we control the time.

Test Plan: ttl_test in normal and valgrind run

Reviewers: dhruba, haobo, sdong, yhchiang

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18399
2014-05-02 07:13:51 -07:00
Igor Canadi 76c3dbf5b5 Make ttl_test a bit more robust 2014-04-29 12:19:54 -07:00
Igor Canadi f868dcbbed Support for adding TTL-ed column family
Summary:
This enables user to add a TTL column family to normal DB.

Next step should be to expand StackableDB and create StackableColumnFamily, such that users can for example add geo-spatial column families to normal DB.

Test Plan: added a test

Reviewers: dhruba, haobo, ljin

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18201
2014-04-28 20:34:20 -07:00
Igor Canadi 3992aec8fa Support for column families in TTL DB
Summary:
This will enable people using TTL DB to do so with multiple column families. They can also specify different TTLs for each one.

TODO: Implement CreateColumnFamily() in TTL world.

Test Plan: Added a very simple sanity test.

Reviewers: dhruba, haobo, ljin, sdong, yhchiang

Reviewed By: haobo

CC: leveldb, alberts

Differential Revision: https://reviews.facebook.net/D17859
2014-04-22 11:27:33 -07:00
Igor Canadi 588bca2020 RocksDBLite
Summary:
Introducing RocksDBLite! Removes all the non-essential features and reduces the binary size. This effort should help our adoption on mobile.

Binary size when compiling for IOS (`TARGET_OS=IOS m static_lib`) is down to 9MB from 15MB (without stripping)

Test Plan: compiles :)

Reviewers: dhruba, haobo, ljin, sdong, yhchiang

Reviewed By: yhchiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17835
2014-04-15 13:39:26 -07:00
Igor Canadi 3d2fe844ab Merge branch 'master' into columnfamilies
Conflicts:
	db/db_impl.cc
	db/db_impl.h
	db/memtable_list.cc
	db/version_set.cc
2014-04-07 11:31:11 -07:00
sdong 4af1954fd6 Compaction Filter V1 to use old context struct to keep backward compatible
Summary: The previous change D15087 changed existing compaction filter, which makes the commonly used class not backward compatible. Revert the older interface. Use a new interface for V2 instead.

Test Plan: make all check

Reviewers: haobo, yhchiang, igor

CC: danguo, dhruba, ljin, igor, leveldb

Differential Revision: https://reviews.facebook.net/D17223
2014-04-02 14:57:51 -07:00
Igor Canadi e8168382c4 Merge branch 'master' into columnfamilies
Conflicts:
	db/db_impl.cc
	include/rocksdb/options.h
	util/options.cc
2014-03-25 11:09:40 -07:00
Danny Guo b47812fba6 [rocksdb] new CompactionFilterV2 API
Summary:
This diff adds a new CompactionFilterV2 API that roll up the
decisions of kv pairs during compactions. These kv pairs must share the
same key prefix. They are buffered inside the db.

    typedef std::vector<Slice> SliceVector;
    virtual std::vector<bool> Filter(int level,
                                 const SliceVector& keys,
                                 const SliceVector& existing_values,
                                 std::vector<std::string>* new_values,
                                 std::vector<bool>* values_changed
                                 ) const = 0;

Application can override the Filter() function to operate
on the buffered kv pairs. More details in the inline documentation.

Test Plan:
make check. Added unit tests to make sure Keep, Delete,
Change all works.

Reviewers: haobo

CCs: leveldb

Differential Revision: https://reviews.facebook.net/D15087
2014-03-24 20:47:53 -07:00
Yueh-Hsuan Chiang cda4006e87 Enhance partial merge to support multiple arguments
Summary:
* PartialMerge api now takes a list of operands instead of two operands.
* Add min_pertial_merge_operands to Options, indicating the minimum
  number of operands to trigger partial merge.
* This diff is based on Schalk's previous diff (D14601), but it also
  includes necessary changes such as updating the pure C api for
  partial merge.

Test Plan:
* make check all
* develop tests for cases where partial merge takes more than two
  operands.

TODOs (from Schalk):
* Add test with min_partial_merge_operands > 2.
* Perform benchmarks to measure the performance improvements (can probably
  use results of task #2837810.)
* Add description of problem to doc/index.html.
* Change wiki pages to reflect the interface changes.

Reviewers: haobo, igor, vamsi

Reviewed By: haobo

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D16815
2014-03-24 17:57:13 -07:00
Igor Canadi 457c78eb89 [CF] db_stress for column families
Summary:
I had this diff for a while to test column families implementation. Last night, I ran it sucessfully for 10 hours with the command:

   time ./db_stress --threads=30 --ops_per_thread=200000000 --max_key=5000 --column_families=20 --clear_column_family_one_in=3000000 --verify_before_write=1  --reopen=50 --max_background_compactions=10 --max_background_flushes=10 --db=/tmp/db_stress

It is ready to be committed :)

Test Plan: Ran it for 10 hours

Reviewers: dhruba, haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16797
2014-03-11 12:06:12 -07:00
Igor Canadi b06840aa7d [CF] Rethinking ColumnFamilyHandle and fix to dropping column families
Summary:
The change to the public behavior:
* When opening a DB or creating new column family client gets a ColumnFamilyHandle.
* As long as column family handle is alive, client can do whatever he wants with it, even drop it
* Dropped column family can still be read from (using the column family handle)
* Added a new call CloseColumnFamily(). Client has to close all column families that he has opened before deleting the DB
* As soon as column family is closed, any calls to DB using that column family handle will fail (also any outstanding calls)

Internally:
* Ref-counting ColumnFamilyData
* New thread-safety for ColumnFamilySet
* Dropped column families are now completely dropped and their memory cleaned-up

Test Plan: added some tests to column_family_test

Reviewers: dhruba, haobo, kailiu, sdong

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16101
2014-02-12 13:47:09 -08:00
Igor Canadi 9385a5247e [RocksDB] [Column Family] Interface proposal
Summary:
<This diff is for Column Family branch>

Sharing some of the work I've done so far. This diff compiles and passes the tests.

The biggest change is in options.h - I broke down Options into two parts - DBOptions and ColumnFamilyOptions. DBOptions is DB-specific (env, create_if_missing, block_cache, etc.) and ColumnFamilyOptions is column family-specific (all compaction options, compresion options, etc.). Note that this does not break backwards compatibility at all.

Further, I created DBWithColumnFamily which inherits DB interface and adds new functions with column family support. Clients can transparently switch to DBWithColumnFamily and it will not break their backwards compatibility.
There are few methods worth checking out: ListColumnFamilies(), MultiNewIterator(), MultiGet() and GetSnapshot(). [GetSnapshot() returns the snapshot across all column families for now - I think that's what we agreed on]

Finally, I made small changes to WriteBatch so we are able to atomically insert data across column families.

Please provide feedback.

Test Plan: make check works, the code is backward compatible

Reviewers: dhruba, haobo, sdong, kailiu, emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14445
2013-12-18 13:08:22 -08:00
Igor Canadi 0a5ec49895 Make DBWithTTL more like StackableDB
Summary: Now DBWithTTL takes DB* and can behave more like StackableDB. This saves us a lot of duplicate work by defining interfaces

Test Plan: ttl_test with ASAN - OK

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14481
2013-12-06 16:10:43 -08:00
Mayank Agarwal 92e8316118 Make GetDbIdentity pure virtual and also implement it for StackableDB, DBWithTTL
Summary: As title

Test Plan: make clean and make

Reviewers: igor

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14469
2013-12-05 12:02:31 -08:00
Igor Canadi 3ce3658411 DB::GetOptions()
Summary: We need access to options for BackupableDB

Test Plan: make check

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14331
2013-11-25 15:51:50 -08:00
Igor Canadi 11c26bd4a4 [RocksDB] Interface changes required for BackupableDB
Summary: This is part of https://reviews.facebook.net/D14295 -- smaller diff that is easier to review

Test Plan: make asan_check

Reviewers: dhruba, haobo, emayanke

Reviewed By: emayanke

CC: leveldb, kailiu, reconnect.grayhat

Differential Revision: https://reviews.facebook.net/D14301
2013-11-25 12:39:23 -08:00
Igor Canadi ec0acfbca1 Fix stack overflow
Summary:
Sure, let me put 8 bytes in that int32_t.

Brought to you by ASAN!

Test Plan: ttl_test

Reviewers: dhruba, haobo, kailiu, emayanke

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14193
2013-11-18 20:56:21 -08:00
Pascal Borreli 443e04e62d Fixed typos 2013-11-16 11:21:34 +00:00
kailiu 21587760b9 Fixing the warning messages captured under mac os # Consider using git commit -m 'One line title' && arc diff. # You will save time by running lint and unit in the background.
Summary: The work to make sure mac os compiles rocksdb is not completed yet. But at least we can start cleaning some warnings captured only by g++ from mac os..

Test Plan: ran make in mac os

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14049
2013-11-12 20:05:28 -08:00
Mayank Agarwal f837f5b1c9 Making the transaction log iterator more robust
Summary:
strict essentially means that we MUST find the startsequence. Thus we should return if starteSequence is not found in the first file in case strict is set. This will take care of ending the iterator in case of permanent gaps due to corruptions in the log files
Also created NextImpl function that will have internal variable to distinguish whether Next is being called from StartSequence or by application.
Set NotFoudn::gaps status to give an indication of gaps happeneing.
Polished the inline documentation at various places

Test Plan:
* db_repl_stress test
* db_test relating to transaction log iterator
* fbcode/wormhole/rocksdb/rocks_log_iterator
* sigma production machine sigmafio032.prn1

Reviewers: dhruba

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13689
2013-11-04 20:49:03 -08:00
Haobo Xu 8cbe5bb56b [RocksDB] Add OnCompactionStart to CompactionFilter class
Summary: This is to give application compaction filter a chance to access context information of a specific compaction run. For example, depending on whether a compaction goes through all data files, the application could do things differently.

Test Plan: make check

Reviewers: dhruba, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13683
2013-10-31 13:36:43 -07:00
Mayank Agarwal 56305221c4 Unify DeleteFile and DeleteWalFiles
Summary:
This is to simplify rocksdb public APIs and improve the code quality.
Created an additional parameter to ParseFileName for log sub type and improved the code for deleting a wal file.
Wrote exhaustive unit-tests in delete_file_test
Unification of other redundant APIs can be taken up in a separate diff

Test Plan: Expanded delete_file test

Reviewers: dhruba, haobo, kailiu, sdong

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13647
2013-10-25 08:32:14 -07:00
Dhruba Borthakur 4463b11cad Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.
Summary: Migrate names of properties from 'leveldb' prefix to 'rocksdb' prefix.

Test Plan: make check

Reviewers: emayanke, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13311
2013-10-06 00:14:26 -07:00
Dhruba Borthakur a143ef9b38 Change namespace from leveldb to rocksdb
Summary:
Change namespace from leveldb to rocksdb. This allows a single
application to link in open-source leveldb code as well as
rocksdb code into the same process.

Test Plan: compile rocksdb

Reviewers: emayanke

Reviewed By: emayanke

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13287
2013-10-04 11:59:26 -07:00
Mayank Agarwal 854d236361 Add backward compatible option in GetLiveFiles to choose whether to not Flush first
Summary:
As explained in comments in GetLiveFiles in db.h, this option will cause flush to be skipped in GetLiveFiles because some use-cases use GetSortedWalFiles after GetLiveFiles to generate more complete snapshots.
Using GetSortedWalFiles after GetLiveFiles allows us to not Flush in GetLiveFiles first because wals have everything.
Note: file deletions will be disabled before calling GLF or GSWF so live logs will not move to archive logs or get delted.
Note: Manifest file is truncated to a proper value in GLF, so it will always reply from the proper wal files on a restart

Test Plan: make

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D13257
2013-10-04 10:20:10 -07:00
Rajat Goel 11c65021fb Revert "Minor fixes found while trying to compile it using clang on Mac OS X"
This reverts commit 5f2c136c32.
2013-09-15 23:01:26 -07:00
Rajat Goel 5f2c136c32 Minor fixes found while trying to compile it using clang on Mac OS X 2013-09-15 22:06:14 -07:00
Mayank Agarwal e2a093a6c3 Fix delete in db_ttl.cc
Summary: should delete the proper variable

Test Plan: make all check

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12921
2013-09-13 11:16:27 -07:00
Mayank Agarwal 4b785aab05 Add logdata to ttl
Summary: Ttl-write makes a new writebatch and calls Write on the base db. It should recognize LogData also

Test Plan: make

Reviewers: dhruba, haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12747
2013-09-05 13:52:47 -07:00
Xing Jin 42c109cc2e New ldb command to convert compaction style
Summary:
Add new command "change_compaction_style" to ldb tool. For
universal->level, it shows "nothing to do". For level->universal, it
compacts all files into a single one and moves the file to level 0.

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

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

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

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: vamsi, emayanke

Differential Revision: https://reviews.facebook.net/D12603
2013-09-04 13:13:08 -07:00
Mayank Agarwal b1d09f1a51 Fix build failing becasue of ttl-keymayexist
Summary: PutValues calls Flush in ttl_test which clears memtables. KeyMayExist called after that will not be able to read those key-values

Test Plan: make all check OPT=-g

Reviewers:leveldb
2013-09-01 21:06:04 -07:00
Mayank Agarwal f121c4f504 KeyMayExist for ttl
Summary: value needed to be filtered of timestamp

Test Plan: ./ttl_test

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12657
2013-09-01 00:28:18 -07:00
Dhruba Borthakur 1186192ed1 Replace include/leveldb with include/rocksdb.
Summary: Replace include/leveldb with include/rocksdb.

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

Differential Revision: https://reviews.facebook.net/D12489
2013-08-23 10:51:00 -07:00
Deon Nicholas b87dcae1a3 Made merge_oprator a shared_ptr; and added TTL unit tests
Test Plan:
- make all check;
- make release;
- make stringappend_test; ./stringappend_test

Reviewers: haobo, emayanke

Reviewed By: haobo

CC: leveldb, kailiu

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

Test Plan: make all check

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

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

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

Reviewers: haobo, emayanke, vamsi, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12315
2013-08-19 11:42:47 -07:00
Mayank Agarwal f1bf169484 Counter for merge failure
Summary:
With Merge returning bool, it can keep failing silently(eg. While faling to fetch timestamp in TTL). We need to detect this through a rocksdb counter which can get bumped whenever Merge returns false. This will also be super-useful for the mcrocksdb-counter service where Merge may fail.
Added a counter NUMBER_MERGE_FAILURES and appropriately updated db/merge_helper.cc

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

Test Plan: make all check

Reviewers: dnicholas, haobo, dhruba, vamsi

CC: leveldb

Differential Revision: https://reviews.facebook.net/D12129
2013-08-13 14:25:42 -07:00
sumeet 3b81df34bd Separate compaction filter for each compaction
Summary:
If we have same compaction filter for each compaction,
application cannot know about the different compaction processes.
Later on, we can put in more details in compaction filter for the
application to consume and use it according to its needs. For e.g. In
the universal compaction, we have a compaction process involving all the
files while others don't involve all the files. Applications may want to
collect some stats only when during full compaction.

Test Plan: run existing unit tests

Reviewers: haobo, dhruba

Reviewed By: dhruba

CC: xinyaohu, leveldb

Differential Revision: https://reviews.facebook.net/D12057
2013-08-13 10:56:20 -07:00
Deon Nicholas e37eb21e92 minor change to fix build 2013-08-06 11:02:19 -07:00
Deon Nicholas c2d7826ced [RocksDB] [MergeOperator] The new Merge Interface! Uses merge sequences.
Summary:
Here are the major changes to the Merge Interface. It has been expanded
to handle cases where the MergeOperator is not associative. It does so by stacking
up merge operations while scanning through the key history (i.e.: during Get() or
Compaction), until a valid Put/Delete/end-of-history is encountered; it then
applies all of the merge operations in the correct sequence starting with the
base/sentinel value.

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

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

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

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

Reviewers: haobo, dhruba, zshao, emayanke

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11499
2013-08-05 20:14:32 -07:00
Mayank Agarwal 73f9518b21 Fix build
Summary: remove reference

Test Plan: make OPT=-g

Reviewers:

CC:

Task ID: #

Blame Rev:
2013-08-05 19:22:12 -07:00
Mayank Agarwal 1d7b4765c3 Expose base db object from ttl wrapper
Summary: rocksdb replicaiton will need this when writing value+TS from master to slave 'as is'

Test Plan: make

Reviewers: dhruba, vamsi, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11919
2013-08-05 18:44:14 -07:00
Mayank Agarwal cacd812fb2 Support user's compaction filter in TTL logic
Summary: TTL uses compaction filter to purge key-values and required the user to not pass one. This diff makes it accommodating of user's compaciton filter. Added test to ttl_test

Test Plan: make; ./ttl_test

Reviewers: dhruba, haobo, vamsi

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11973
2013-08-05 11:28:01 -07:00
Mayank Agarwal c42485f67c Merge operator for ttl
Summary: Implemented a TtlMergeOperator class which inherits from MergeOperator and is TTL aware. It strips out timestamp from existing_value and attaches timestamp to new_value, calling user-provided-Merge in between.

Test Plan: make all check

Reviewers: haobo, dhruba

Reviewed By: haobo

CC: leveldb

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

Test Plan: make all check;db_stress for 1 hour

Reviewers: dhruba, haobo

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D11853
2013-08-01 09:07:46 -07:00