Commit Graph

5707 Commits

Author SHA1 Message Date
Daniel Black
a8bf4d63f9 Make format shows wrong curl command for retrieving clang-format-diff.py
Summary:
Previously:

$ make format
Makefile:104: Warning: Compiling in debug mode. Don't use the resulting binary in production
build_tools/format-diff.sh
You didn't have clang-format-diff.py available in your computer!
You can download it by running:
    curl http://goo.gl/iUW1u2
Makefile:868: recipe for target 'format' failed
make: *** [format] Error 128

$ curl http://goo.gl/iUW1u2 > ~/bin/clang-format-diff.py
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   276    0   276    0     0    148      0 --:--:--  0:00:01 --:--:--   148m

$ more ~/bin/clang-format-diff.py
<HTML>
<HEAD>
<TITLE>Moved Permanently</TITLE>
</HEAD>
<BODY BGCOLOR="#FFFFFF" TEXT="#000000">
<H1>Moved Permanently</H1>
The document has moved <A HREF="https://raw.github.com/leaningtech/duetto-clang/master/tools/clang-format/clang-format-diff.py">here</A>.
</BODY>
</HTML>
Closes https://github.com/facebook/rocksdb/pull/1680

Differential Revision: D4338495

Pulled By: yiwu-arbug

fbshipit-source-id: e2b24d8
2016-12-15 20:24:12 -08:00
siddontang
8f5d24ae68 C API: support get usage and pinned_usage for cache
Summary: Closes https://github.com/facebook/rocksdb/pull/1671

Differential Revision: D4327453

Pulled By: yiwu-arbug

fbshipit-source-id: bcdbc65
2016-12-15 17:24:17 -08:00
Daniel Black
0ab6fc167f Gcc-7 buffer size insufficient
Summary:
Bunch of commits related to insufficient buffer size. Errors in individual commits.
Closes https://github.com/facebook/rocksdb/pull/1673

Differential Revision: D4332127

Pulled By: IslamAbdelRahman

fbshipit-source-id: 878f73c
2016-12-14 19:24:26 -08:00
Daniel Black
b7239bf7e0 Gcc 7 fallthrough
Summary:
hopefully the last of the gcc-7 compile errors
Closes https://github.com/facebook/rocksdb/pull/1675

Differential Revision: D4332106

Pulled By: IslamAbdelRahman

fbshipit-source-id: 139448c
2016-12-14 19:24:25 -08:00
Daniel Black
477b6ea578 std::remove_if requires <algorithm>
Summary:
fixes error (that occurred on gcc-7):

error:

util/env_basic_test.cc: In member function 'virtual rocksdb::Status rocksdb::NormalizingEnvWrapper::GetChildren(const string&, std::vector<std::__cxx11::basic_string<char> >*)':
util/env_basic_test.cc:27:21: error: 'remove_if' is not a member of 'std'
       result->erase(std::remove_if(result->begin(), result->end(),
                     ^~~
Closes https://github.com/facebook/rocksdb/pull/1674

Differential Revision: D4331221

Pulled By: ajkr

fbshipit-source-id: 9bbdc78
2016-12-14 17:09:14 -08:00
Andrew Kryczka
83f9a6fd21 Fail BackupEngine::Open upon meta-file read error
Summary:
We used to treat any failure to read a backup's meta-file as if the backup were corrupted; however, we should distinguish corruption errors from errors in the backup Env. This fixes an issue where callers would get inconsistent results from GetBackupInfo() if they called it on an engine that encountered Env error during initialization. Now we fail Initialize() in this case so callers cannot invoke GetBackupInfo() on such engines.
Closes https://github.com/facebook/rocksdb/pull/1654

Differential Revision: D4318573

Pulled By: ajkr

fbshipit-source-id: f7a7c54
2016-12-14 16:39:15 -08:00
Karthikeyan Radhakrishnan
a79eae4b01 Add pcache documentation images
Summary:
Adding images that are used in persistent read cache documentation.
Closes https://github.com/facebook/rocksdb/pull/1666

Differential Revision: D4328220

Pulled By: IslamAbdelRahman

fbshipit-source-id: 767e0d0
2016-12-14 11:54:22 -08:00
Islam AbdelRahman
d71e728c7a Print user collected properties in sst_dump
Summary:
Include a dump of user_collected_properties in sst_dump
Closes https://github.com/facebook/rocksdb/pull/1668

Differential Revision: D4325078

Pulled By: IslamAbdelRahman

fbshipit-source-id: 226b6d6
2016-12-14 11:24:11 -08:00
Jonathan Lee
7004a6f7b8 Add missing copyright header
Summary:
"examples/c_simple_example.c" did not have a proper copyright header.
Closes https://github.com/facebook/rocksdb/pull/1670

Differential Revision: D4327445

Pulled By: yiwu-arbug

fbshipit-source-id: a70389e
2016-12-14 10:24:13 -08:00
Adam Retter
3cdfaeca3f Fixes for MSVC compilation
Summary: Closes https://github.com/facebook/rocksdb/pull/1669

Differential Revision: D4327421

Pulled By: yiwu-arbug

fbshipit-source-id: 661ee0b
2016-12-14 10:24:13 -08:00
Daniel Black
e097222e64 util/logging.cc: buffer of insufficient size (gcc-7 -Werror=format-length)
Summary:
util/logging.cc💯13: error: output may be truncated before the last format character [-Werror=format-length=]
 std::string NumberToHumanString(int64_t num) {
             ^~~~~~~~~~~~~~~~~~~
util/logging.cc:106:59: note: format output between 3 and 19 bytes into a destination of size 16
     snprintf(buf, sizeof(buf), "%" PRIi64 "K", num / 1000);
Closes https://github.com/facebook/rocksdb/pull/1653

Differential Revision: D4318687

Pulled By: yiwu-arbug

fbshipit-source-id: 3a5c931
2016-12-13 18:39:14 -08:00
Daniel Black
cfc34d7c4e Missing break in case in DBTestBase::CurrentOptions
Summary:
Found by gcc-7 compile error.

This appeared to be a fault as these options seems too different.
Closes https://github.com/facebook/rocksdb/pull/1667

Differential Revision: D4324174

Pulled By: yiwu-arbug

fbshipit-source-id: 0f65383
2016-12-13 18:39:14 -08:00
Daniel Black
bfbcec2339 Gcc 7 error expansion to defined
Summary:
sorry if these gcc-7/clang-4 cleanups are getting tedious.
Closes https://github.com/facebook/rocksdb/pull/1658

Differential Revision: D4318792

Pulled By: yiwu-arbug

fbshipit-source-id: 8e85891
2016-12-13 18:39:14 -08:00
Bassam Tabbara
6653e32ac2 build: make it easier to pass PORTABLE
Summary:
currently when running a portable build we have to do the following

  PORTABLE=1 make ...

this commit adds support for the following

  make PORTABLE=1 ...

this might be seem subtle but it makes PORTABLE like all other
makefile args and simplifies invocation from numerous build systems
including things like ExternalProject_Add in cmake.

Signed-off-by: Bassam Tabbara <bassam.tabbara@quantum.com>
Closes https://github.com/facebook/rocksdb/pull/1643

Differential Revision: D4315870

Pulled By: yiwu-arbug

fbshipit-source-id: ee43755
2016-12-13 14:39:17 -08:00
Daniel Black
67adc937b6 intentional fallthough (prevents gcc-7/clang-4 error)
Summary:
db/memtable.cc: In member function 'void rocksdb::MemTable::Update(rocksdb::SequenceNumber, const rocksdb::Slice&, const rocksdb::Slice&)':
db/memtable.cc:736:11: error: this statement may fall through [-Werror=implicit-fallthrough=]
           }
           ^
db/memtable.cc:738:9: note: here
         default:
         ^~~~~~~
cc1plus: all warnings being treated as errors

closes #1650
Closes https://github.com/facebook/rocksdb/pull/1655

Differential Revision: D4318696

Pulled By: yiwu-arbug

fbshipit-source-id: 1a8981c
2016-12-13 14:39:17 -08:00
Islam AbdelRahman
1a146f89c7 break Flush wait for dropped CF
Summary:
In FlushJob we dont do the Flush if the CF is dropped
https://github.com/facebook/rocksdb/blob/master/db/flush_job.cc#L184-L188

but inside WaitForFlushMemTable we keep waiting forever even if the CF is dropped.
Closes https://github.com/facebook/rocksdb/pull/1664

Differential Revision: D4321032

Pulled By: IslamAbdelRahman

fbshipit-source-id: 6e2b25d
2016-12-13 14:09:12 -08:00
Daniel Black
c3e5ee7154 util/histogram.cc: HistogramStat::toString buffer insufficient
Summary:
Increased buffer size to 1650.

util/histogram.cc: In member function 'std::__cxx11::string rocksdb::HistogramStat::ToString() const':
util/histogram.cc:189:13: error: '%.2f' directive output truncated writing between 4 and 313 bytes into a region of size 0 [-Werror=format-length=]
 std::string HistogramStat::ToString() const {
             ^~~~~~~~~~~~~
util/histogram.cc:205:30: note: format output between 69 and 1614 bytes into a destination of size 200
            Percentile(99.99));
                              ^
cc1plus: all warnings being treated as errors
Makefile:1521: recipe for target 'util/histogram.o' failed
Closes https://github.com/facebook/rocksdb/pull/1660

Differential Revision: D4318820

Pulled By: yiwu-arbug

fbshipit-source-id: 45ae6ea
2016-12-13 14:09:12 -08:00
Daniel Black
5334d8b44c table/block_based_table_builder.cc: intentional fallthrough - comment to match gcc pattern
Summary:
The gcc-7 code for parsing comments (libcpp/lex.c) didn't match
the intentional fallthough in this comment.

table/block_based_table_builder.cc: In member function 'void rocksdb::BlockBasedTableBuilder::WriteRawBlock(const rocksdb::Slice&, rocksdb::CompressionType, rocksdb::BlockHandle*)':
table/block_based_table_builder.cc:754:22: error: this statement may fall through [-Werror=implicit-fallthrough=]
         assert(false);
                      ^
table/block_based_table_builder.cc:756:7: note: here
       case kCRC32c: {
       ^~~~
cc1plus: all warnings being treated as errors
Closes https://github.com/facebook/rocksdb/pull/1661

Differential Revision: D4318817

Pulled By: yiwu-arbug

fbshipit-source-id: e67d171
2016-12-13 13:54:15 -08:00
Yi Wu
36d42e65d0 Disable test to unblock travis build
Summary:
The two tests keep failing in travis. Disable them and will fix later.
Closes https://github.com/facebook/rocksdb/pull/1648

Differential Revision: D4316389

Pulled By: yiwu-arbug

fbshipit-source-id: 0a370e7
2016-12-13 11:54:14 -08:00
siddontang
b57dd9262a C API: support writebatch delete range
Summary:
Seem that writebatch delete range can work now, so I add C API for later use.

Btw, can we use this feature in production now?
Closes https://github.com/facebook/rocksdb/pull/1647

Differential Revision: D4314534

Pulled By: ajkr

fbshipit-source-id: e835165
2016-12-13 11:24:18 -08:00
Islam AbdelRahman
2ba59b5a1e Disallow ingesting files into dropped CFs
Summary:
This PR update IngestExternalFile to return an error if we try to ingest a file into a dropped CF.

Right now if IngestExternalFile want to flush a memtable, and it's ingesting a file into a dropped CF, it will wait forever since flushing is not possible for the dropped CF
Closes https://github.com/facebook/rocksdb/pull/1657

Differential Revision: D4318657

Pulled By: IslamAbdelRahman

fbshipit-source-id: ed6ea2b
2016-12-13 00:54:14 -08:00
Daniel Black
1f6f7e3e89 cast to signed char in ldb_cmd_test for ppc64le
Summary:
char is unsigned on power by default causing this test to fail with the FF case. ppc64 return 255 while x86 returned -1. Casting works on both platforms.
Closes https://github.com/facebook/rocksdb/pull/1500

Differential Revision: D4308775

Pulled By: yiwu-arbug

fbshipit-source-id: db3e6e0
2016-12-12 14:39:18 -08:00
Andrew Kryczka
243975d5da More accurate error status for BackupEngine::Open
Summary:
Some users are assuming NotFound means the backup does not
exist at the provided path, which is a reasonable assumption. We need to
stop returning NotFound for system errors.

Depends on #1644
Closes https://github.com/facebook/rocksdb/pull/1645

Differential Revision: D4312233

Pulled By: ajkr

fbshipit-source-id: 5343c10
2016-12-12 13:24:21 -08:00
Andrew Kryczka
f0c509e2c8 Return finer-granularity status from Env::GetChildren*
Summary:
It'd be nice to use the error status type to distinguish
between user error and system error. For example, GetChildren can fail
listing a backup directory's contents either because a bad path was provided
(user error) or because an operation failed, e.g., a remote storage service
call failed (system error). In the former case, we want to continue and treat
the backup directory as empty; in the latter case, we want to immediately
propagate the error to the caller.

This diff uses NotFound to indicate user error and IOError to indicate
system error. Previously IOError indicated both.
Closes https://github.com/facebook/rocksdb/pull/1644

Differential Revision: D4312157

Pulled By: ajkr

fbshipit-source-id: 51b4f24
2016-12-12 12:54:13 -08:00
Andrew Kryczka
dc64f46b1c Add db_bench option for stderr logging
Summary:
The info log file ("LOG") is stored in the db directory by default. When the db is on a distributed env, this is unnecessarily slow. So, I added an option to db_bench to just print the info log messages to stderr.
Closes https://github.com/facebook/rocksdb/pull/1641

Differential Revision: D4309348

Pulled By: ajkr

fbshipit-source-id: 1e6f851
2016-12-09 16:54:14 -08:00
Jonathan Lee
2cabdb8f44 Increase buffer size
Summary:
When compiling with GCC>=7.0.0, "db/internal_stats.cc" fails to compile as the data being written to the buffer potentially exceeds its size.

This fix simply doubles the size of the buffer, thus accommodating the max possible data size.
Closes https://github.com/facebook/rocksdb/pull/1635

Differential Revision: D4302162

Pulled By: yiwu-arbug

fbshipit-source-id: c76ad59
2016-12-09 11:54:22 -08:00
Jonathan Lee
4a17b47bb5 Remove unnecessary header include
Summary:
Remove "util/testharness.h" from list of includes for "db/db_filesnapshot.cc", as it wasn't being used and thus caused an extraneous dependency on gtest.
Closes https://github.com/facebook/rocksdb/pull/1634

Differential Revision: D4302146

Pulled By: yiwu-arbug

fbshipit-source-id: e900c0b
2016-12-09 11:54:21 -08:00
Mike Kolupaev
8c2b921fdf Fixed a crash in debug build in flush_job.cc
Summary:
It was doing `&range_del_iters[0]` on an empty vector. Even though the resulting pointer is never dereferenced, it's still bad for two reasons:
* the practical reason: it crashes with `std::out_of_range` exception in our debug build,
* the "C++ standard lawyer" reason: it's undefined behavior because, in `std::vector` implementation, it probably "dereferences" a null pointer, which is invalid even though it doesn't actually read the pointed memory, just converts a pointer into a reference (and then flush_job.cc converts it back to pointer); nullptr references are undefined behavior.
Closes https://github.com/facebook/rocksdb/pull/1612

Differential Revision: D4265625

Pulled By: al13n321

fbshipit-source-id: db26fb9
2016-12-09 10:39:12 -08:00
Islam AbdelRahman
20ce081fae Fix issue where IngestExternalFile insert blocks in block cache with g_seqno=0
Summary:
When we Ingest an external file we open it to read some metadata and first/last key
during doing that we insert blocks into the block cache with global_seqno = 0

If we move the file (did not copy it) into the DB, we will use these blocks with the wrong seqno in the read path
Closes https://github.com/facebook/rocksdb/pull/1627

Differential Revision: D4293332

Pulled By: yiwu-arbug

fbshipit-source-id: 3ce5523
2016-12-08 13:39:18 -08:00
Andrew Kryczka
5241e0dbfc fix db_bench argument type
Summary: Closes https://github.com/facebook/rocksdb/pull/1633

Differential Revision: D4298161

Pulled By: yiwu-arbug

fbshipit-source-id: 2c7af35
2016-12-08 11:09:14 -08:00
Jonathan Lee
c04f6a0b4c Specify shell in makefile
Summary:
The second variable "SHELL" simply tells make explicitly which shell to use, instead of allowing it to default to "/bin/sh", which may or may not be Bash.

However, simply defining the second variable by itself causes make to throw an error concerning a circular definition, as it would be attempting to use the "shell" command while simultaneously trying to set which shell to use. Thus, the first variable "BASH_EXISTS" is defined such that make already knows about "/path/to/bash" before trying to use it to set "SHELL".

A more technically correct solution would be to edit the makefile itself to make it compatible with non-bash shells (see the original Issue discussion for details). However, as it seems very few of the people working on this project were building with non-bash shells, I figured this solution would be good enough.
Closes https://github.com/facebook/rocksdb/pull/1631

Differential Revision: D4295689

Pulled By: yiwu-arbug

fbshipit-source-id: e4f9532
2016-12-07 22:24:15 -08:00
zhangjinpeng1987
45c7ce1377 CompactRangeOptions C API
Summary:
Add C API for CompactRangeOptions.
Closes https://github.com/facebook/rocksdb/pull/1596

Differential Revision: D4252339

Pulled By: yiwu-arbug

fbshipit-source-id: f768f93
2016-12-07 17:54:14 -08:00
Andrew Kryczka
2c2ba68247 db_stress support for range deletions
Summary:
made db_stress capable of adding range deletions to its db and verifying their correctness. i'll make db_crashtest.py use this option later once the collapsing optimization (https://github.com/facebook/rocksdb/pull/1614) is committed because currently it slows down the test too much.
Closes https://github.com/facebook/rocksdb/pull/1625

Differential Revision: D4293939

Pulled By: ajkr

fbshipit-source-id: d3beb3a
2016-12-07 13:09:24 -08:00
Andrew Kryczka
b821984d31 DeleteRange read path end-to-end tests
Summary: Closes https://github.com/facebook/rocksdb/pull/1592

Differential Revision: D4246260

Pulled By: ajkr

fbshipit-source-id: ce03fa2
2016-12-07 12:54:17 -08:00
Artemiy Kolesnikov
2f4fc539c6 Compaction::IsTrivialMove relaxing
Summary:
IsTrivialMove returns true if no input file overlaps with output_level+1 with more than max_compaction_bytes_ bytes.
Closes https://github.com/facebook/rocksdb/pull/1619

Differential Revision: D4278338

Pulled By: yiwu-arbug

fbshipit-source-id: 994c001
2016-12-07 11:54:11 -08:00
dhruba borthakur
1dce75b2e2 Update USERS.md
Summary: Closes https://github.com/facebook/rocksdb/pull/1630

Differential Revision: D4293200

Pulled By: IslamAbdelRahman

fbshipit-source-id: 9c81f85
2016-12-07 11:24:14 -08:00
dhruba borthakur
304b3c706b Update USERS.md
Summary: Closes https://github.com/facebook/rocksdb/pull/1629

Differential Revision: D4293183

Pulled By: IslamAbdelRahman

fbshipit-source-id: 759ea92
2016-12-07 11:24:14 -08:00
Andrew Kryczka
fa50fffaf5 Option to expand range tombstones in db_bench
Summary:
When enabled, this option replaces range tombstones with a sequence of
point tombstones covering the same range. This can be used to A/B test perf of
range tombstones vs sequential point tombstones, and help us find the cross-over
point, i.e., the size of the range above which range tombstones outperform point
tombstones.
Closes https://github.com/facebook/rocksdb/pull/1594

Differential Revision: D4246312

Pulled By: ajkr

fbshipit-source-id: 3b00b23
2016-12-06 18:09:14 -08:00
Yi Wu
c26a4d8e8a Fix compile error in trasaction_lock_mgr.cc
Summary:
Fix error on mac/windows build since they don't recognize `uint`.
Closes https://github.com/facebook/rocksdb/pull/1624

Differential Revision: D4287139

Pulled By: yiwu-arbug

fbshipit-source-id: b7cc88f
2016-12-06 14:39:16 -08:00
Islam AbdelRahman
ed8fbdb560 Add EventListener::OnExternalFileIngested() event
Summary:
Add EventListener::OnExternalFileIngested() to allow user to subscribe to external file ingestion events
Closes https://github.com/facebook/rocksdb/pull/1623

Differential Revision: D4285844

Pulled By: IslamAbdelRahman

fbshipit-source-id: 0b95a88
2016-12-06 14:09:17 -08:00
Manuel Ung
2005c88a75 Implement non-exclusive locks
Summary:
This is an implementation of non-exclusive locks for pessimistic transactions. It is relatively simple and does not prevent starvation (ie. it's possible that request for exclusive access will never be granted if there are always threads holding shared access). It is done by changing `KeyLockInfo` to hold an set a transaction ids, instead of just one, and adding a flag specifying whether this lock is currently held with exclusive access or not.

Some implementation notes:
- Some lock diagnostic functions had to be updated to return a set of transaction ids for a given lock, eg. `GetWaitingTxn` and `GetLockStatusData`.
- Deadlock detection is a bit more complicated since a transaction can now wait on multiple other transactions. A BFS is done in this case, and deadlock detection depth is now just a limit on the number of transactions we visit.
- Expirable transactions do not work efficiently with shared locks at the moment, but that's okay for now.
Closes https://github.com/facebook/rocksdb/pull/1573

Differential Revision: D4239097

Pulled By: lth

fbshipit-source-id: da7c074
2016-12-05 17:39:17 -08:00
Yi Wu
0b0f235724 Mention IngestExternalFile changes in HISTORY.md
Summary:
I hit the land button too fast and didn't include the line.
Closes https://github.com/facebook/rocksdb/pull/1622

Differential Revision: D4281316

Pulled By: yiwu-arbug

fbshipit-source-id: c7b38e0
2016-12-05 16:09:11 -08:00
Yi Wu
23db48e8d8 Update HISTORY.md for 5.0 branch
Summary:
These changes are included in the new branch-cut.
Closes https://github.com/facebook/rocksdb/pull/1621

Differential Revision: D4281015

Pulled By: yiwu-arbug

fbshipit-source-id: d88858b
2016-12-05 15:39:11 -08:00
Mike Kolupaev
beb36d9c1e Fixed CompactionFilter::Decision::kRemoveAndSkipUntil
Summary:
Embarassingly enough, the first time I tried to use my new feature in logdevice it crashed with this assertion failure:

  db/pinned_iterators_manager.h:30: void rocksdb::PinnedIteratorsManager::StartPinning(): Assertion `pinning_enabled == false' failed

The issue was that `pinned_iters_mgr_.StartPinning()` was called but `pinned_iters_mgr_.ReleasePinnedData()` wasn't.
Closes https://github.com/facebook/rocksdb/pull/1611

Differential Revision: D4265622

Pulled By: al13n321

fbshipit-source-id: 747b10f
2016-12-05 15:24:11 -08:00
Islam AbdelRahman
67f37cf198 Allow user to specify a CF for SST files generated by SstFileWriter
Summary:
Allow user to explicitly specify that the generated file by SstFileWriter will be ingested in a specific CF.
This allow us to persist the CF id in the generated file
Closes https://github.com/facebook/rocksdb/pull/1615

Differential Revision: D4270422

Pulled By: IslamAbdelRahman

fbshipit-source-id: 7fb954e
2016-12-05 14:24:16 -08:00
Anton Safonov
9053fe2a5c Made delete_obsolete_files_period_micros option dynamic
Summary:
Made delete_obsolete_files_period_micros option dynamic. It can be updating using DB::SetDBOptions().
Closes https://github.com/facebook/rocksdb/pull/1595

Differential Revision: D4246569

Pulled By: tonek

fbshipit-source-id: d23f560
2016-12-05 14:24:16 -08:00
Islam AbdelRahman
edde954e7b fix clang build
Summary:
override is missing for FilterV2
Closes https://github.com/facebook/rocksdb/pull/1606

Differential Revision: D4263832

Pulled By: IslamAbdelRahman

fbshipit-source-id: d8b337a
2016-12-01 18:39:10 -08:00
Yi Wu
56281f3a97 Add memtable_insert_with_hint_prefix_size option to db_bench
Summary:
Add memtable_insert_with_hint_prefix_size option to db_bench
Closes https://github.com/facebook/rocksdb/pull/1604

Differential Revision: D4260549

Pulled By: yiwu-arbug

fbshipit-source-id: cee5ef7
2016-12-01 16:54:16 -08:00
Islam AbdelRahman
4a21b1402c Cache heap::downheap() root comparison (optimize heap cmp call)
Summary:
Reduce number of comparisons in heap by caching which child node in the first level is smallest (left_child or right_child)
So next time we can compare directly against the smallest child

I see that the total number of calls to comparator drops significantly when using this optimization

Before caching (~2mil key comparison for iterating the DB)
```
$ DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readseq" --db="/dev/shm/heap_opt" --use_existing_db --disable_auto_compactions --cache_size=1000000000  --perf_level=2
readseq      :       0.338 micros/op 2959201 ops/sec;  327.4 MB/s user_key_comparison_count = 2000008
```
After caching (~1mil key comparison for iterating the DB)
```
$ DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readseq" --db="/dev/shm/heap_opt" --use_existing_db --disable_auto_compactions --cache_size=1000000000 --perf_level=2
readseq      :       0.309 micros/op 3236801 ops/sec;  358.1 MB/s user_key_comparison_count = 1000011
```

It also improves
Closes https://github.com/facebook/rocksdb/pull/1600

Differential Revision: D4256027

Pulled By: IslamAbdelRahman

fbshipit-source-id: 76fcc66
2016-12-01 13:39:14 -08:00
Islam AbdelRahman
e39d080871 Fix travis (compile for clang < 3.9)
Summary:
Travis fail because it uses clang 3.6 which don't recognize
`__attribute__((__no_sanitize__("undefined")))`
Closes https://github.com/facebook/rocksdb/pull/1601

Differential Revision: D4257175

Pulled By: IslamAbdelRahman

fbshipit-source-id: fb4d1ab
2016-12-01 10:09:22 -08:00