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

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

Summary: https://www.facebook.com/groups/rocksdb.dev/permalink/590438347721350/

Test Plan: compiles

Reviewers: sdong, ljin, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19197

Commit 6634844d by sdong
Two small fixes in db_test

Summary:
Two fixes:
(1) WalDir to pick a directory under TmpDir to allow two tests running in parallel without impacting each other
(2) kBlockBasedTableWithWholeKeyHashIndex is disabled by mistake (I assume). Enable it.

Test Plan: ./db_test

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: nkg-, igor, dhruba, haobo, leveldb

Differential Revision: https://reviews.facebook.net/D19389

This reverts commit 6634844d.

Summary:
In this patch, we enhance HashLinkList memtable to reduce performance outliers when a bucket contains too many entries. We switch to skip list for this case to enable binary search.

Add threshold_use_skiplist parameter to determine when a bucket needs to switch to skip list.

The new data structure is documented in comments in the codes.

Test Plan:
make all check
set threshold_use_skiplist in several tests

Reviewers: yhchiang, haobo, ljin

Reviewed By: yhchiang, ljin

Subscribers: nkg-, xjin, dhruba, yhchiang, leveldb

Differential Revision: https://reviews.facebook.net/D19299

Summary:
Two fixes:
(1) WalDir to pick a directory under TmpDir to allow two tests running in parallel without impacting each other
(2) kBlockBasedTableWithWholeKeyHashIndex is disabled by mistake (I assume). Enable it.

Test Plan: ./db_test

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: nkg-, igor, dhruba, haobo, leveldb

Differential Revision: https://reviews.facebook.net/D19389

Summary:
    Now that the arena is used to allocate space for hashskiplist's bucket. The bucket size
    need to be set small enough to avoid "should_flush_" failure in memtable's assertion.

Test Plan:
    make all check

Reviewers: sdong

Reviewed By: sdong

Subscribers: igor

Differential Revision: https://reviews.facebook.net/D19371

Summary: files_by_size_ is sorted by time in case of universal compaction. However, Version::files_ is also sorted by time. So no need for files_by_size_

Test Plan:
1) make check with the change
2) make check with `assert(last_index == c->input_version_->files_[level].size() - 1);` in compaction picker

Reviewers: dhruba, haobo, yhchiang, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19125

Summary:
    Bloomfilter and hashskiplist's buckets_ allocated by memtable's arena
    DynamicBloom: pass arena via constructor, allocate space in SetTotalBits
    HashSkipListRep: allocate space of buckets_ using arena.
       do not delete it in deconstructor because arena would take care of it.
    Several test files are changed.

Test Plan:
    make all check

Reviewers: ljin, haobo, yhchiang, sdong

Reviewed By: sdong

Subscribers: igor, dhruba

Differential Revision: https://reviews.facebook.net/D19335

Summary:
Correct the library loading for zlib in RocksJava: zlib should
be loaded by loadLibrary("z") instead of loadLibrary("zlib").

Test Plan:
make rocksdbjava
cd java
make db_bench
./jdb_bench.sh --compression_type=zlib

Reviewers: sdong, ljin, ankgup87

Reviewed By: ankgup87

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19341

[Java] Merge pull request #183 --- Add statistics collector utility

Summary:
1. Add statistics collector which collects statistics periodically at a period specified by caller.
2. Added unit-test for StatsCollector

make rocksdbjava
make test

Reviewers: haobo, yhchiang, sdong, dhruba, rsumbaly, zzbennett, swapnilghike
Reviewed By: yhchiang
CC: leveldb

Differential Revision: https://reviews.facebook.net/19215

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

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

Summary:
Fixed the following warning:

util/options.cc: In constructor ‘rocksdb::ColumnFamilyOptions::ColumnFamilyOptions(const rocksdb::Options&)’:
util/options.cc:157:58: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
   if (max_bytes_for_level_multiplier_additional.size() < num_levels) {
                                                             ^

Test Plan: make all check

Reviewers: haobo, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19293

Summary: It seems to me that when ever function MemTableRep::GetIterator(const Slice& slice) is used, we can use MemTableRep::GetDynamicPrefixIterator() instead. Just delete it to simplify the codes.

Test Plan: make all check

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: xjin, dhruba, haobo, leveldb

Differential Revision: https://reviews.facebook.net/D19281

Summary:
Currently, when num_levels has been changed to > 7, internally
it will not resize max_bytes_for_level_multiplier_additional.
As a result, max_bytes_for_level_multiplier_additional.size() will
be smaller than num_levels, which causes heap-buffer-overflow.

Test Plan: make all check

Reviewers: haobo, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19275

Summary:
Move stats related member variables of FileMetaData to the bottom to
improve cache locality of normal DB operations.

Test Plan: make

Reviewers: haobo, ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19287

Summary:
This diff allows compaction to reclaim storage more effectively.
In the current design, compactions are mainly triggered based on
the file sizes.  However, since deletion entries does not have
value, files which have many deletion entries are less likely
to be compacted.  As a result, it may took a while to make
deletion entries to be compacted.

This diff address issue by compensating the size of deletion
entries during compaction process: the size of each deletion
entry in the compaction process is augmented by 2x average
value size.  The diff applies to both leveled and universal
compacitons.

Test Plan:
develop CompactionDeletionTrigger
make db_test
./db_test

Reviewers: haobo, igor, ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19029

Summary:
RandomGenerator::Generate() currently has an assertion len < data_.size().
However, it is actually fine to have len == data_.size().
This diff change the assertion to len <= data_.size().

Test Plan:
make db_bench
./db_bench

Reviewers: haobo, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19269

Summary:
Enable the random values in Java DB Bench to be generated based
on the compression_ratio specified in the command-line arguments.

Test Plan:
make rocksdbjava
java/jdb_bench.sh

Reviewers: sdong, ankgup87, haobo

Reviewed By: haobo

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19101

Corrected the output message in mac-install-gflags.sh

Summary:
Revert the default setting of InitFromCmdLineArgs() as all the callers
currently provide full set of arguments.

Test Plan:
make reduce_levels_test
./reduce_levels_test

Reviewers: haobo, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19257

Summary:
Fixed the following compile error.
    tools/reduce_levels_test.cc:89:31: error: no matching function for call to 'InitFromCmdLineArgs'
      LDBCommand* level_reducer = LDBCommand::InitFromCmdLineArgs(args);
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ./util/ldb_cmd.h:56:22: note: candidate function not viable: requires 3 arguments, but 1 was provided
      static LDBCommand* InitFromCmdLineArgs(
                         ^
    ./util/ldb_cmd.h:62:22: note: candidate function not viable: requires 4 arguments, but 1 was provided
      static LDBCommand* InitFromCmdLineArgs(
                         ^
    1 error generated.

Test Plan:
make reduce_levels_test
./reduce_levels_test

Reviewers: haobo, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19251

Summary:
Fixed the following compile error.
    tools/reduce_levels_test.cc:89:31: error: no matching function for call to 'InitFromCmdLineArgs'
      LDBCommand* level_reducer = LDBCommand::InitFromCmdLineArgs(args);
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ./util/ldb_cmd.h:56:22: note: candidate function not viable: requires 3 arguments, but 1 was provided
      static LDBCommand* InitFromCmdLineArgs(
                         ^
    ./util/ldb_cmd.h:62:22: note: candidate function not viable: requires 4 arguments, but 1 was provided
      static LDBCommand* InitFromCmdLineArgs(
                         ^
    1 error generated.

Test Plan:
make reduce_levels_test
./reduce_levels_test

Reviewers: haobo, ljin, sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19251

Summary:
This diff fixes the following compilation error in mac.
  ./third-party/rapidjson/reader.h:422:31: error: comparison of constant 256 with expression of type 'Ch' (aka 'char') is always true
        [-Werror,-Wtautological-constant-out-of-range-compare]
                                  if ((sizeof(Ch) == 1 || e < 256) && escape[(unsigned char)e])
                                                          ~ ^ ~~~
  1 error generated.

Test Plan: make db_test

Reviewers: haobo, sdong, igor, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19245

typo

Summary: Currently ldb tool dump keys either in ascii format or hex format - neither is ideal if the key has a binary structure and is not readable in ascii. This diff also allows LDB tool to be customized in ways beyond DB options.

Test Plan: verify that key formatter works with some simple db with binary key.

Reviewers: sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19209

Summary: as title

Test Plan: make release

Reviewers: haobo, sdong, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19227

Summary: as title

Test Plan: none

Reviewers: ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19239

Summary:
Add one entry to HISTORY.md that is failed to be added.
Move two other ones to the right location.

Test Plan: Only document

Reviewers: haobo, ljin

Subscribers: dhruba, yhchiang, leveldb

Differential Revision: https://reviews.facebook.net/D19233

Summary: as requested by mark

Test Plan: make release

Reviewers: sdong, haobo

Reviewed By: haobo

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19221