Summary: Add tests for MemTableList
Test Plan: run test
Reviewers: yhchiang, kradhakrishnan, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36735
Summary:
Fix a compile error in ROCKSDB_LITE in db/db_impl.cc
related to internal_stats.
Test Plan: make OPT=-DROCKSDB_LITE shared_lib
Reviewers: sdong, igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36819
Summary: "make commit-prereq" uses "make release" which overrides OPT, so ROCKSDB_LITE is not covered. Fix it by using "make static_lib"
Test Plan: Run it and see it fail (which is expected)
Reviewers: yhchiang, meyering, rven, anthony, kradhakrishnan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36813
Summary:
Fix a compilation error in ROCKSDB_LITE in db/internal_stats.h
Other compilation errors will be fixed in a separate diff.
Test Plan: make OPT=-DROCKSDB_LITE
Reviewers: sdong, igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36807
Summary:
Add a test case:
Write some keys without sync, flush, write other keys and do sync. Before flush finishes, host crashes and unsync data is dropped.
Tag the new test as disabled since it is not passing.
Test Plan: Run the test
Reviewers: MarkCallaghan, rven, anthony, igor, kradhakrishnan
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36741
Summary:
This fixes two problems:
1) the env should not be created twice when use_existing_db is false
2) the env dtor should run before cachedev_fd_ is closed.
Task ID: #
Blame Rev:
Test Plan:
Revert Plan:
Database Impact:
Memcache Impact:
Other Notes:
EImportant:
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36795
Summary: I don't think we need to use whole-archive to include jemalloc. This change only affects our development builds -- it does not affect our open source builds (which don't support jemalloc) or our fbcode third-party2 builds (which use open-source build codepaths).
Test Plan:
make
verify that jemalloc is running by running `MALLOC_CONF="prof:true" ./cache_test` and observing that file was created
Reviewers: MarkCallaghan
Reviewed By: MarkCallaghan
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36783
Summary: Other than making some class members private, this is a documentation-only change
Test Plan: unit tests
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36567
Summary: Add a script, which checks out changes from a list of tags, build them and load the same data into it. In the last, checkout the target build and make sure it can successfully open DB and read all the data. It is implemented through ldb tool, because ldb tool is available from all previous builds so that we don't have to cross build anything.
Test Plan: Run the script.
Reviewers: yhchiang, rven, anthony, kradhakrishnan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36639
Summary: Now EnvOptions uses unsanitized DB options. bytes_per_sync is tuned off when rate_limiter is used, but this change doesn't take effort.
Test Plan: See different I/O pattern in db_bench running fillseq.
Reviewers: yhchiang, kradhakrishnan, rven, anthony, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36723
Summary: These two files are test binaries and are not included in TESTS in Makefile.
Test Plan: `make clean` now deletes those files, too
Reviewers: sdong, kradhakrishnan, meyering
Reviewed By: kradhakrishnan, meyering
Subscribers: kradhakrishnan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36705
Summary:
When building rocksdbjava and rocksdbjavastatic, create -fPIC-enabled
binaries in a temporary subdirectory, jl/.
* Makefile (java_libobjects): New variable.
(java_libobjects): New rule.
(CLEAN_FILES): Arrange for "make clean" to remove that temporary dir.
(rocksdbjavastatic): Depend on the new variable.
Remove useless OPT=... line.
(rocksdbjava): Likewise.
Test Plan:
JAVA_HOME=/usr/local/jdk-7u67-64 PATH=$JAVA_HOME/bin:$PATH \
make rocksdbjavastatic
Reviewers: yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36645
Summary: Now trivial move is only triggered when moving from level n to n+1. With dynamic level base, it is possible that file is moved from level 0 to level n, while levels from 1 to n-1 are empty. Extend trivial move to this case.
Test Plan: Add a more unit test of sequential loading. Non-trivial compaction happened without the patch and now doesn't happen.
Reviewers: rven, yhchiang, MarkCallaghan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba, IslamAbdelRahman
Differential Revision: https://reviews.facebook.net/D36669
Summary:
Fix the following compilation error in flashcache.cc on Mac
Undefined symbols for architecture x86_64:
"rocksdb::NewFlashcacheAwareEnv(rocksdb::Env*, int)", referenced from:
rocksdb::Benchmark::Open(rocksdb::Options*) in db_bench.o
Test Plan: make db_bench
Reviewers: sdong, igor, rven
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36657
Summary:
* src.mk (JNI_NATIVE_SOURCES): New variable, so we don't have to use
a glob in Makefile
* Makefile (JNI_NATIVE_SOURCES): Remove glob-using definition, now
that the explicit list of sources is in src.mk.
Test Plan:
Run this:
JAVA_HOME=/usr/local/jdk-7u67-64 PATH=$JAVA_HOME/bin:$PATH \
make rocksdbjava
Reviewers: yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36633
Summary:
As described in https://github.com/facebook/rocksdb/issues/563, we should add minor version to SONAME, since we break ABI with minor releases.
I also turned PLATFORM_SHARED_VERSIONED to true by default. This is true in LevelDB and it was switched to false by D15117 for no apparent reason. It should only be false for iOS.
Test Plan: `make shared_lib` produced librocksdb.dylib.3.10.0
Reviewers: sdong, yhchiang, meyering
Reviewed By: meyering
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36573
Summary:
After this diff, when a user submits a diff from Facebook's VPN
network, we'll automatically trigger a jenkins test. Once jenkins test
is done, we'll update the diff with test results.
Test Plan:
Made sure that jenkins build is triggered on `arc diff` and
that result is reflected back on the diff
Reviewers: sdong, rven, kradhakrishnan, anthony, yhchiang
Reviewed By: anthony
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36555
Summary:
There are some cases when flachcache file descriptor was
already allocated (i.e. fb-MySQL). Then NewFlashcacheAwareEnv returns an
error at open() because fd was already assigned. This diff adds another
function to instantiate FlashcacheAwareEnv, with pre-allocated fd cachedev_fd.
Test Plan: Tested with MyRocks using this function, then worked
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba, MarkCallaghan, rven
Differential Revision: https://reviews.facebook.net/D36447
Summary: Now we add warnings when user configures compression and the compression is not supported.
Test Plan:
Configured compression to non-supported values. Observed messages in my log:
2015/03/26-12:17:57.586341 7ffb8a496840 [WARN] Compression type chosen for level 2 is not supported: LZ4. RocksDB will not compress data on level 2.
2015/03/26-12:19:10.768045 7f36f15c5840 [WARN] Compression type chosen is not supported: LZ4. RocksDB will not compress data.
Reviewers: rven, sdong, yhchiang
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35979
Summary:
When GNU parallel is available, "make check" tests are now run in parallel.
When /dev/shm is usable, we tell those tests to create temporary files therein.
Now, the longest-running single test, db_test, (which is composed of hundreds of sub-tests)
is no longer run sequentially: instead, each of its sub-tests is run independently, and can
be parallelized along with all other tests. To make that process easier, this change
creates a temporary directory, "t/", in which it puts a small script for each of those
subtests. The output from each parallel-run test is now saved in t/log-TEST_NAME.
When GNU parallel is not available, we run the tests in sequence, just as before.
If GNU parallel is available and you don't like the default of running one subtest
per core, you can invoke "make J=1 check" to run only one test at a time.
Beware: this will take a long time, and it starts with the two longest-running tests, so you
will wait for a long time before seeing any results. Instead, if you want to use fewer resources
but still see useful progress, try "make J=60% check". That will attempt to ensure that 60% of
the cores are occupied by test runs.
To watch progress of individual tests (duration, success (PASS-or-FAIL), name), run "make watch-log"
in the same directory from another window. That will start with something like this:
and when complete should show numbers/names like this:
Every 0.1s: sort -k7,7nr -k4,4gr LOG|perl -n -e '@a=split("\t",$_,-1); $t=$a[8]; $t =~ s,^\./,,;' -e '$t =~ s, >.*,,; chomp $t;' -e '$t =~ /.*--gtest_filter=... Wed Apr 1 10:51:42 2015
152.221 PASS t/DBTest.FileCreationRandomFailure
109.280 PASS t/DBTest.EncodeDecompressedBlockSizeTest
82.315 PASS reduce_levels_test
77.812 PASS t/DBTest.CompactionFilterWithValueChange
73.236 PASS backupable_db_test
63.428 PASS deletefile_test
57.248 PASS table_test
55.665 PASS prefix_test
49.816 PASS t/DBTest.RateLimitingTest
...
Test Plan:
Timings (measured so as to exclude compile and link times):
With this change, all tests complete in 2m40s on a system for which nproc prints 32.
Prior to this this change, "make check" would take 24.5 minutes on that same system.
Here are durations (in seconds) of the longest-running subtests:
152.435 PASS t/DBTest.FileCreationRandomFailure
107.070 PASS t/DBTest.EncodeDecompressedBlockSizeTest
81.391 PASS ./reduce_levels_test
71.587 PASS ./backupable_db_test
61.746 PASS ./deletefile_test
57.960 PASS ./table_test
55.230 PASS ./prefix_test
54.060 PASS t/DBTest.CompactionFilterWithValueChange
48.873 PASS t/DBTest.RateLimitingTest
47.569 PASS ./fault_injection_test
46.593 PASS t/DBTest.Randomized
42.662 PASS t/DBTest.CompactionFilter
31.793 PASS t/DBTest.SparseMerge
30.612 PASS t/DBTest.CompactionFilterV2
25.891 PASS t/DBTest.GroupCommitTest
23.863 PASS t/DBTest.DynamicLevelMaxBytesBase
22.976 PASS ./rate_limiter_test
18.942 PASS t/DBTest.OptimizeFiltersForHits
16.851 PASS ./env_test
15.399 PASS t/DBTest.CompactionFilterV2WithValueChange
14.827 PASS t/DBTest.CompactionFilterV2NULLPrefix
Reviewers: igor, sdong, rven, yhchiang, igor.sugak
Reviewed By: igor.sugak
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D35379
Summary:
Fix build break on travis build:
$ OPT=-DTRAVIS V=1 make unity && make clean && OPT=-DTRAVIS V=1 make db_test && ./db_test
......
In file included from unity.cc:65:0:
./table/plain_table_key_coding.cc: In member function ‘rocksdb::Status rocksdb::PlainTableKeyDecoder::NextPrefixEncodingKey(const char*, const char*, rocksdb::ParsedInternalKey*, rocksdb::Slice*, size_t*, bool*)’:
./table/plain_table_key_coding.cc:224:3: error: reference to ‘EntryType’ is ambiguous
EntryType entry_type;
^
In file included from ./db/table_properties_collector.h:9:0,
from ./db/builder.h:11,
from ./db/builder.cc:10,
from unity.cc:1:
./include/rocksdb/table_properties.h:81:6: note: candidates are: enum rocksdb::EntryType
enum EntryType {
^
In file included from unity.cc:65:0:
./table/plain_table_key_coding.cc:16:6: note: enum rocksdb::{anonymous}::EntryType
enum EntryType : unsigned char {
^
./table/plain_table_key_coding.cc:231:51: error: ‘entry_type’ was not declared in this scope
const char* pos = DecodeSize(key_ptr, limit, &entry_type, &size);
^
make: *** [unity.o] Error 1
Test Plan:
OPT=-DTRAVIS V=1 make unity
And make sure it doesn't break anymore.
Reviewers: yhchiang, kradhakrishnan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36549
Summary:
This adds p99.9 and p99.99 response times to the benchmark report and
adds a second report, report2.txt that has tests listed in test order rather
than the time in which they were run, so overwrite tests are listed for
all thread counts, then update etc.
Also changes fillseq to compress all levels to avoid write-amp from rewriting
uncompressed files when they reach the first level to compress.
Increase max_write_buffer_number to avoid stalls during fillseq and make
max_background_flushes agree with max_write_buffer_number.
See https://gist.github.com/mdcallag/297ff4316a25cb2988f7 for an example
of the new report (report2.txt)
Task ID: #
Blame Rev:
Test Plan:
Revert Plan:
Database Impact:
Memcache Impact:
Other Notes:
EImportant:
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36537
Summary:
Currently users have no idea a key is add, delete or merge from TablePropertiesCollector call back. Add a new function to add it.
Also refactor the codes so that
(1) make table property collector and internal table property collector two separate data structures with the later one now exposed
(2) table builders only receive internal table properties
Test Plan: Add cases in table_properties_collector_test to cover both of old and new ways of using TablePropertiesCollector.
Reviewers: yhchiang, igor.sugak, rven, igor
Reviewed By: rven, igor
Subscribers: meyering, yoshinorim, maykov, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D35373
Summary:
If accumulated_num_non_deletions_ were ever smaller than
accumulated_num_deletions_, the computation of
"accumulated_num_non_deletions_ - accumulated_num_deletions_"
would result in a logically "negative" value, but since
the two operands are unsigned (uint64_t), the result corresponding
to e.g., -1 would 2^64-1.
Instead, return 0 in that case.
Test Plan:
- ensure "make check" still passes
- temporarily add an "abort();" call in the new "if"-block, and
observe that it fails in some test cases. However, note that
this case is triggered only when the two numbers are equal.
Thus, no test case triggers the erroneous behavior this
change is designed to avoid. If anyone can construct a
scenario in which that bug would be triggered, I'll be
happy to add a test case.
Reviewers: ljin, igor, rven, igor.sugak, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36489
Summary: Int is used for level size targets when options_.level_compaction_dynamic_level_bytes=true, which will cause overflow when database grows big. Fix it.
Test Plan: Add a new unit test which fails without the fix.
Reviewers: rven, yhchiang, MarkCallaghan, igor
Reviewed By: igor
Subscribers: leveldb, dhruba, yoshinorim
Differential Revision: https://reviews.facebook.net/D36453
Summary: In some db_test tests sync points are not cleared which will cause unexpected results in the next tests. Clean them up in test cleaning up.
Test Plan:
Run the same tests that used to fail:
build using USE_CLANG=1 and run
./db_test --gtest_filter="DBTest.CompressLevelCompaction:*DBTestUniversalCompactionParallel*"
Reviewers: rven, yhchiang, igor
Reviewed By: igor
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36429
Summary:
This diff fixes a crash found when an empty database is opened in readonly mode.
We now check the number of levels before we open the DB as a compacted DB.
Test Plan: DBTest.EmptyCompactedDB
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36327
Summary:
Fix the make unity build. The local stats variable name was shadowing a
global stats variable.
Test Plan:
Run the build
OPT=-DTRAVIS V=1 make unity
Reviewers: sdong, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36285
Summary: After you run `arc diff`, just run `build_tools/trigger_jenkins_test.sh` and Jenkins will test your diff!
Test Plan: Triggered a build to jenkins
Reviewers: sdong, rven, IslamAbdelRahman, anthony, yhchiang, meyering
Reviewed By: meyering
Subscribers: meyering, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36021
Summary:
After recent change of DBTest.DynamicCompactionOptions, occasionally hit another non-deterministic case where L0 showdown is triggered while timeout should not triggered for hard limit.
Fix it by increasing L0 slowdown trigger at the same time.
Test Plan: Run the failed test.
Reviewers: igor, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D36219
Summary:
With this change, we use L1 and up to store compaction outputs in universal compaction.
The compaction pick logic stays the same. Outputs are stored in the largest "level" as possible.
If options.num_levels=1, it behaves all the same as now.
Test Plan:
1) convert most of existing unit tests for universal comapaction to include the option of one level and multiple levels.
2) add a unit test to cover parallel compaction in universal compaction and run it in one level and multiple levels
3) add unit test to migrate from multiple level setting back to one level setting
4) add a unit test to insert keys to trigger multiple rounds of compactions and verify results.
Reviewers: rven, kradhakrishnan, yhchiang, igor
Reviewed By: igor
Subscribers: meyering, leveldb, MarkCallaghan, dhruba
Differential Revision: https://reviews.facebook.net/D34539
Summary:
Just couple of small changes:
1. removed signal_test, since it doesn't seem useful and we don't even run it as part of `make check`
2. moved perf_context_test to TESTS instead of PROGRAMS
3. `make release` probably shouldn't compile benchmarks. We currently rely on `make release` building db_bench (via Jenkins), so I left db_bench there.
This is just a minor cleanup. We need to rethink our targets since they are a bit messy right now. We can do this during our tech debt week.
Test Plan: make release
Reviewers: anthony, rven, yhchiang, sdong, meyering
Reviewed By: meyering
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36171
Summary:
The --stats_interval_seconds determines interval for stats reporting
and overrides --stats_interval when set. I also changed tools/benchmark.sh
to report stats every 60 seconds so I can avoid trying to figure out a
good value for --stats_interval per test and per storage device.
Task ID: #6631621
Blame Rev:
Test Plan:
run tools/run_flash_bench, look at output
Revert Plan:
Database Impact:
Memcache Impact:
Other Notes:
EImportant:
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36189
Summary:
Cleaning up log files can do heavy IO, since we call ftruncate() in the destructor. We don't want to call ftruncate() in user threads.
This diff moves cleaning to background threads (flush and compaction)
Test Plan: make check, will also run valgrind
Reviewers: yhchiang, rven, MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D36177
Summary:
This makes run_flash_bench.sh configurable. Previously it was hardwired for 1B keys and tests
ran for 12 hours each. That kept me from using it. This makes it configuable, adds more tests,
makes the duration per-test configurable and refactors the test scripts.
Adds the seekrandomwhilemerging test to db_bench which is the same as seekrandomwhilewriting except
the writer thread does Merge rather than Put.
Forces the stall-time column in compaction IO stats to use a fixed format (H:M:S) which makes
it easier to scrape and parse. Also adds an option to AppendHumanMicros to force a fixed format.
Sometimes automation and humans want different format.
Calls thread->stats.AddBytes(bytes); in db_bench for more tests to get the MB/sec summary
stats in the output at test end.
Adds the average ingest rate to compaction IO stats. Output now looks like:
https://gist.github.com/mdcallag/2bd64d18be1b93adc494
More information on the benchmark output is at https://gist.github.com/mdcallag/db43a58bd5ac624f01e1
For benchmark.sh changes default RocksDB configuration to reduce stalls:
* min_level_to_compress from 2 to 3
* hard_rate_limit from 2 to 3
* max_grandparent_overlap_factor and max_bytes_for_level_multiplier from 10 to 8
* L0 file count triggers from 4,8,12 to 4,12,20 for (start,stall,stop)
Task ID: #6596829
Blame Rev:
Test Plan:
run tools/run_flash_bench.sh
Revert Plan:
Database Impact:
Memcache Impact:
Other Notes:
EImportant:
- begin *PUBLIC* platform impact section -
Bugzilla: #
- end platform impact -
Reviewers: igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36075
Summary: Most of the approach is copied from WebSQL's MySQL branch. It's nice that we can do this without touching core RocksDB code.
Test Plan: Compiles and runs. Didn't test flashback code, as I don't have flashback device and most if it is c/p
Reviewers: MarkCallaghan, sdong
Reviewed By: sdong
Subscribers: rven, lgalanis, kradhakrishnan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35391
Summary:
This fixes two bugs: "make clean" would never remove the generated
file, util/build_version.cc, and since D33591, would be regenerated
only if it were absent.
* Makefile (clean): Remove the generated file.
(util/build_version.cc): Depend on the no-prereq FORCE target,
so that this target's rules are always run.
Since this is a generated file, make it read-only.
Also, be sure to remove the temporary file when it is the same
as the original.
Test Plan:
Ensure that we attempt regeneration every time.
Make it empty with an up-to-date time stamp and demonstrate
that it is rebuilt with the expected content:
$ : > util/build_version.cc
$ make util/build_version.o
GEN util/build_version.cc
GEN util/build_version.d
GEN util/build_version.cc
CC util/build_version.o
$ cat util/build_version.cc
#include "build_version.h"
const char* rocksdb_build_git_sha = "rocksdb_build_git_sha:v3.10-2-gb30e72a";
const char* rocksdb_build_git_date = "rocksdb_build_git_date:2015-03-27";
const char* rocksdb_build_compile_date = __DATE__;
Reviewers: igor.sugak, sdong, ljin, igor, rven
Reviewed By: rven
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D36087
Summary:
Assign the string properties to const string variables under the
DB::Properties namespace. This helps catch typos during compilation and
also consolidates the property definition in one place.
Test Plan: Run rocksdb unit tests
Reviewers: sdong, yoshinorim, igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D35991
Summary:
Whenever we add new tests in db_sanity_test.cc, the verification test
will fail since the old version db_sanity_test.cc does not have the
newly added test. This patch makes auto_sanity_test.sh always use
the db_sanity_test.cc of the newer commit.
As a result, a macro guard is added to allow db_sanity_test.cc to be
backward compatible.
Test Plan: tools/auto_sanity_check.sh
Reviewers: sdong, rven, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35997
The error was:
util/logging.cc: In function 'int rocksdb::AppendHumanMicros(uint64_t, char*, int)':
error: util/logging.cc:41:39: integer overflow in expression [-Werror=overflow]
} else if (micros < 1000000l * 60 * 60) {
^
error: util/logging.cc:41:39: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
Summary: It's useful to know if we have compression support or no
Test Plan:
Observed this in my LOG:
2015/03/26-10:34:35.460681 7f5b322b7840 Snappy supported
2015/03/26-10:34:35.460682 7f5b322b7840 Zlib supported
2015/03/26-10:34:35.460686 7f5b322b7840 Bzip supported
2015/03/26-10:34:35.460687 7f5b322b7840 LZ4 NOT supported
Reviewers: sdong, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D35955