Summary: as title

Test Plan: ran db_bench to gather stats

Reviewers: haobo, sdong

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16059

Summary:
In MacOS, I got issue with `Footer`'s default constructor, which initialized the magic number with some random number instead of 0.
With investigation, I found we forgot to make the kInvalidTableMagicNumber to be static. As a result, kInvalidTableMagicNumber was assgined to `table_magic_number_` before it is initialized (which will be populated with random number).

Test Plan: passed current unit tests; also passed the unit tests for the incoming diff which used the default footer.

Reviewers: yhchiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16077

Summary:
This patch optimized Get() code paths by avoiding malloc of iterators. Iterator creation is moved to mem table rep implementations, where a callback is called when any key is found. This is the same practice as what we do in (SST) table readers.

db_bench result for readrandom following a writeseq, with no compression, single thread and tmpfs, we see throughput improved to 144958 from 139027, about 3%.

Test Plan: make all check

Reviewers: dhruba, haobo, igor

Reviewed By: haobo

CC: leveldb, yhchiang

Differential Revision: https://reviews.facebook.net/D14685

Summary:
* Fixed the compression state array size bug.
* Temporarily disable running `DoCompressionTest()` against bzip, which will fail the test.

Test Plan: make && ./table_test

Reviewers: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16065

Support for LZ4 compression.

Summary:
Looks like gnu++11 is not very portable (see https://github.com/facebook/rocksdb/issues/80). We don't (yet) depend on any extensions of gnu++11, so I think we should switch back to c++11.

More on this topic here: http://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Extensions.html

Test Plan: make check works :)

Reviewers: kailiu, dhruba, haobo

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D16053

Summary:
We are going to expose properties of all tables to end users through "some" db interface.
However, current design doesn't naturally fit for this need, which is because:

1. If a table presents in table cache, we cannot simply return the reference to its table properties, because the table may be destroy after compaction (and we don't want to hold the ref of the version).
2. Copy table properties is OK, but it's slow.

Thus in this diff, I change the table reader's interface to return a shared pointer (for const table properties), instead a const refernce.

Test Plan: `make check` passed

Reviewers: haobo, sdong, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15999

Summary:
Fix compilation error with gcc 4.7

Test Plan:
make clean
make

Reviewers:

CC:

Task ID: #

Blame Rev:

doc: table_stats_collectors -> table_properties_collectors.

Summary:
This diff enables the command line tool `sst_dump` to work for sst files
under plain table format.  Changes include:
  * In tools/sst_dump.cc:
    - add support for plain table format
    - display prefix_extractor information when --show_properties is on
  * In table/format.cc
    - Now the table magic number of a Footer can be later initialized
      via ReadFooterFromFile().
  * In table/meta_bocks:
    - add function ReadTableMagicNumber() that reads the magic number of
      the specified file.

Minor fixes:
 - remove a duplicate #include in table/table_test.cc
 - fix a commentary typo in include/rocksdb/memtablerep.h
 - fix lint errors.

Test Plan:
Runs sst_dump with both block-based and plain-table format files with
different arguments, specifically those with --show-properties and --from.

* sample output:
  https://reviews.facebook.net/P261

Reviewers: kailiu, sdong, xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15903

Summary:
Added an option for readrandom benchmark to run with tailing iterator instead of Get. Benefit of tailing iterator is that it doesn't require locking DB mutex on access.

I also have some results when running on my machine. The results highly depend on number of cache shards. With our current benchmark setting of 4 table cache shards and 6 block cache shards, I don't see much improvements of using tailing iterator. In that case, we're probably seeing cache mutex contention.

Here are the results for different number of shards

    cache shards       tailing iterator        get
       6                      1.38M           1.16M
      10                      1.58M           1.15M

As soon as we get rid of cache mutex contention, we're seeing big improvements in using tailing iterator vs. ordinary get.

Test Plan: ran regression test

Reviewers: dhruba, haobo, ljin, kailiu, sding

Reviewed By: haobo

CC: tnovak

Differential Revision: https://reviews.facebook.net/D15867

Summary: Nothing major, just an extra return line and posibility of leaking fb in NewRandomRWFile

Test Plan: make check

Reviewers: kailiu, dhruba

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15993

Summary: To speed up the compilation while allowing us to compile in debug mode.

Test Plan:
make: see -O2 enabled
make dbg: didn't see -O2

Reviewers: igor

Reviewed By: igor

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D15969

Remove the unnecessary line led from branch merge.

Fix build in case zlib not found

Conflicts:
	HISTORY.md
	db/db_impl.cc
	db/memtable.cc

crc32c: choose function in static initialization

Before: 4.430 micros/op 225732 ops/sec; 881.8 MB/s (4K per op)
After: 4.125 micros/op 242425 ops/sec; 947.0 MB/s (4K per op)

Summary:
Previous I am too ambitious to hide every detail about table factory
to internal api. However, we cannot pass the compilatoin for external
users since we use table factory as the shared_ptr, which requires
the definition of table factory's destructor.

Test Plan: make check;

Reviewers: sdong, haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15861

Summary: RocksDB doesn't compile on 32-bit architecture apparently. This is attempt to fix some of 32-bit errors. They are reported here: https://gist.github.com/paxos/8789697

Test Plan: RocksDB still compiles on 64-bit :)

Reviewers: kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15825

Summary:
Use super_version insider NewIterator to avoid Ref() each component
separately under mutex
The new added bench shows NewIterator QPS increases from 515K to 719K
No meaningful improvement for multiget I guess due to its relatively small
cost comparing to 90 keys fetch in the test.

Test Plan: unit test and db_bench

Reviewers: igor, sdong

Reviewed By: igor

CC: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D15609

Summary: In PlainTable, use one single byte to represent 8 bytes of internal bytes, if seqID = 0 and it is value type (which should be common for bottom most files). It is to save 7 bytes for uncompressed cases.

Test Plan: make all check

Reviewers: haobo, dhruba, kailiu

Reviewed By: haobo

CC: igor, leveldb

Differential Revision: https://reviews.facebook.net/D15489

Eliminate stdout message when launching a posix thread.

Summary:
Addressed all the issues in https://reviews.facebook.net/D15447.
Now most table-related modules are hidden from user land.

Test Plan: make check

Reviewers: sdong, haobo, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15525

Summary:
Patch  https://reviews.facebook.net/D15591 enabled checksum
verification by default. This caused the unit test to fail.

Test Plan: ./corruption_test

Reviewers: igor, kailiu

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15795

Summary:
VersionSet::next_file_number_ is always assumed to be strictly greater than VersionSet::log_number_. In our new recovery code, we artificially set log_number_  to be (log_number + 1), so that once we flush, we don't recover from the same log file again (this is important because of merge operator non-idempotence)

When we set VersionSet::log_number_ to (log_number + 1), we also have to mark that file number used, such that next_file_number_ is increased to a legal level. Otherwise, VersionSet might assert.

This has not be a problem so far because here's what happens:
1. assume next_file_number is 5, we're recovering log_number 10
2. in DBImpl::Recover() we call MarkFileNumberUsed with 10. This will set VersionSet::next_file_number_ to 11.
3. If there are some updates, we will call WriteTable0ForRecovery(), which will use file number 11 as a new table file and advance VersionSet::next_file_number_ to 12.
4. When we LogAndApply() with log_number 11, assertion is true: assert(11 <= 12);

However, this was a lucky occurrence. Even though this diff doesn't cause a bug, I think the issue is important to fix.

Test Plan: In column families I have different recovery logic and this code path asserted. When adding MarkFileNumberUsed(log_number + 1) assert is gone.

Reviewers: dhruba, kailiu

Reviewed By: kailiu

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15783

Summary: I didn't figure out the reason why the feature of zeroing out earlier sequence ID is disabled in universal compaction. I do see bottommost_level is set correctly. It should simply work if we remove the constraint of universal compaction.

Test Plan: make all check

Reviewers: haobo, dhruba, kailiu, igor

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15423

Summary:
Easy thing goes first. This patch moves arena to internal dir; based
on which, the coming patch will deal with memtable_rep.

Test Plan: make check

Reviewers: haobo, sdong, dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15615

Summary: The default settings enable checksum verification on every read.

Test Plan: make check

Reviewers: haobo

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15591

Conflicts:
	db/db_impl.h