Improve the comment of util/thread_local.h

Summary: Improve the comment of util/thread_local.h

Test Plan: n/a

Reviewers: ljin

Reviewed By: ljin

Differential Revision: https://reviews.facebook.net/D25449
Avoid reloading filter on Get() if cache_index_and_filter_blocks == false

Summary:
This fixes the case that filter policy is missing in SST file, but we
open the table with filter policy on and cache_index_and_filter_blocks =
false. The current behavior is that we will try to load it every time on
Get() but fail.

Test Plan: unit test

Reviewers: yhchiang, igor, rven, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D25455
fix table_test

Summary:
SaveValue expects an internal key but I previously added to table a
user key

Test Plan:
ran the test
Printing number of keys in DB Stats

Summary: It is useful to print out number of keys in DB Stats

Test Plan:
./db_bench --benchmarks fillrandom --num 1000000 -threads 16 -batch_size=16

and watch the outputs in LOG files

Reviewers: MarkCallaghan, ljin, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D24513
db_bench: --batch_size used for write benchmarks too

Summary: Now --bench_size is only used in multireadrandom tests, although the codes allow it to run in all write tests. I don't see a reason why we can't enable it.

Test Plan:
Run
   ./db_bench -benchmarks multirandomwrite --threads=5 -batch_size=16
and see the stats printed out in LOG to make sure batching really happened.

Reviewers: ljin, yhchiang, rven, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D25509
Fix for building RocksDB Java on Mac OS X Yosemite
Correct the log message in VersionEdit

Summary:
When VersionEdit fails in kNewFile3, previously it logs "new-file2 entry".
However, it should be "new-file3 entry."

Test Plan:
make
Merge pull request #361 from adamretter/fix-yosemite-build

Fix for building RocksDB Java on Mac OS X Yosemite
Fix CompactBetweenSnapshots
Added java tests to travis build
Merge pull request #362 from adamretter/travis-jcheck

Added Java build and tests to Travis-CI build
Fix SIGSEGV when declaring Arena after ScopedArenaIterator
[RocksJava] Options Refactoring 3.6

Summary:
Preparational pull request. The main point about these changes is
to enable RocksJava in a next step to provide custom ColumnFamilyOptions.
DBOptions and ColumnFamilyOptions are now available as well as Interfaces
which describe those methods.

Methods in interfaces and class definitions of DBOptions and ColumnFamilyOptions
are ordered according to C++ implementation.

Optimize methods were ported to Java. (OptimizeForPointLookup,
OptimizeLevelCompaction, OptimizeUniversalCompaction).

To align BuiltinComparator with every other Enum it was moved to
a separate file.

A new test was introduced which includes some basic testing of
ColumnFamilyOptions and DBOptions.

Note: The changes are fully downwards compatible.

Test Plan:
make rocksdbjava
make jtest

Differential Revision: https://reviews.facebook.net/D25203