Summary: When rate_bytes_per_sec * refill_period_us_ overflows, the actual limited rate is very low. Handle this case so the rate will be large.

Test Plan: Add a unit test for it.

Reviewers: IslamAbdelRahman, andrewkr

Reviewed By: andrewkr

Subscribers: yiwu, lightmark, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D58929

Summary: Reduce use of argument-dependent name lookup in RocksDB.

Test Plan: 'make check' passed.

Reviewers: andrewkr

Reviewed By: andrewkr

Subscribers: leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D58203

For ease of reuse and customization as a library
  without wrapping.
  WinEnvThreads is a class for replacement.
  WintEnvIO is a class for reuse and behavior override.
  Added private virtual functions for custom override
  of fallocate pread for io classes.

Implement GetUniqueIdFromFile to support new tests and the feature.

Conditionally retrofit thread_posix for use with std::thread
  and reuse the same logic. Posix users continue using Posix interfaces.
  Enable XPRESS compression in test runs.
  Fix master introduced signed/unsigned mismatch.

make preallocation inline with other writable files
  make sure that we map no more than pre-allocated size.

This reverts commit b54c3474.

Revert async file handle change as it causes failures with appveyor

fix typos and remove duplicated words

* Musl libc does not provide adaptive mutex. Added feature test for PTHREAD_MUTEX_ADAPTIVE_NP.

* Musl libc does not provide backtrace(3). Added a feature check for backtrace(3).

* Fixed compiler error.

* Musl libc does not implement backtrace(3). Added platform check for libexecinfo.

* Alpine does not appear to support gcc -pg option. By default (gcc has PIE option enabled) it fails with:

gcc: error: -pie and -pg|p|profile are incompatible when linking

When -fno-PIE and -nopie are used it fails with:

/usr/lib/gcc/x86_64-alpine-linux-musl/5.3.0/../../../../x86_64-alpine-linux-musl/bin/ld: cannot find gcrt1.o: No such file or directory

Added gcc -pg platform test and output PROFILING_FLAGS accordingly. Replaced pg var in Makefile with PROFILING_FLAGS.

* fix segfault when TEST_IOCTL_FRIENDLY_TMPDIR is undefined and default candidates are not suitable

* use ASSERT_DOUBLE_EQ instead of ASSERT_EQ

* When compiled with ROCKSDB_MALLOC_USABLE_SIZE UniversalCompactionFourPaths and UniversalCompactionSecondPathRatio tests fail due to premature memtable flushes on systems with 16-byte alignment. Arena runs out of block space before GenerateNewFile() completes.

Increased options.write_buffer_size.

Comparable with Snappy on comp ratio.
  Implemented using Windows API, does not require external package.
  Avaiable since Windows 8 and server 2012.
  Use -DXPRESS=1 with CMake to enable.

Summary:
Fixed the following compile warnings:

/Users/yhchiang/rocksdb/util/posix_logger.h:32:11: error: unused variable 'kDebugLogChunkSize' [-Werror,-Wunused-const-variable]
const int kDebugLogChunkSize = 128 * 1024;
          ^
/Users/yhchiang/rocksdb/util/coding.h:24:20: error: unused variable 'kMaxVarint32Length' [-Werror,-Wunused-const-variable]
const unsigned int kMaxVarint32Length = 5;
                   ^
2 errors generated.

Test Plan: make clean rocksdb

Reviewers: igor, sdong, anthony, IslamAbdelRahman, rven, kradhakrishnan, adamretter

Reviewed By: adamretter

Subscribers: andrewkr, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D56223

  calls. #ifdef in the source code and make this a default build option.

  by using default implementation for now as it works.

Summary: I broke it in D53781.

Test Plan: tried the same code in util/env_posix.cc and it compiled successfully

Reviewers: sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D54303

Summary:
Added this new function, which returns filename, size, and modified
timestamp for each file in the provided directory. The default implementation
retrieves the metadata sequentially using existing functions. In the next diff
I'll make HdfsEnv override this function to use libhdfs's bulk get function.

This won't work on windows due to the path separator.

Test Plan:
new unit test

  $ ./env_test --gtest_filter=EnvPosixTest.ConsistentChildrenMetadata

Reviewers: yhchiang, sdong

Reviewed By: sdong

Subscribers: IslamAbdelRahman, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D53781

break compatibility with Windows 7. The issue with rotated logs
was fixed other way.

 This change impacts only non-buffered I/O on Windows.
 Currently, there is a buffer per RandomAccessFile
 instance that is protected by a lock. The reason we
 maintain the buffer is non-buffered I/O requires an aligned
 buffer to work.
 XPerf traces demonstrate that we accumulate a considerable
 wait time while waiting for that lock.
 This change enables to set random access buffer size to zero
 which would indicate a per request allocation.
 We are expecting that allocation expense would be much less than
 I/O costs plus wait time due to the fact that the memory heap
 would tend to re-use page aligned allocations especially with the
 use of Jemalloc.
 This change does not affect buffer use as a read_ahead_buffer for
 compaction purposes.

  Use Yield macro to make it a little more portable between platforms.

Summary:
This diff adds support for concurrent adds to the skiplist memtable
implementations.  Memory allocation is made thread-safe by the addition of
a spinlock, with small per-core buffers to avoid contention.  Concurrent
memtable writes are made via an additional method and don't impose a
performance overhead on the non-concurrent case, so parallelism can be
selected on a per-batch basis.

Write thread synchronization is an increasing bottleneck for higher levels
of concurrency, so this diff adds --enable_write_thread_adaptive_yield
(default off).  This feature causes threads joining a write batch
group to spin for a short time (default 100 usec) using sched_yield,
rather than going to sleep on a mutex.  If the timing of the yield calls
indicates that another thread has actually run during the yield then
spinning is avoided.  This option improves performance for concurrent
situations even without parallel adds, although it has the potential to
increase CPU usage (and the heuristic adaptation is not yet mature).

Parallel writes are not currently compatible with
inplace updates, update callbacks, or delete filtering.
Enable it with --allow_concurrent_memtable_write (and
--enable_write_thread_adaptive_yield).  Parallel memtable writes
are performance neutral when there is no actual parallelism, and in
my experiments (SSD server-class Linux and varying contention and key
sizes for fillrandom) they are always a performance win when there is
more than one thread.

Statistics are updated earlier in the write path, dropping the number
of DB mutex acquisitions from 2 to 1 for almost all cases.

This diff was motivated and inspired by Yahoo's cLSM work.  It is more
conservative than cLSM: RocksDB's write batch group leader role is
preserved (along with all of the existing flush and write throttling
logic) and concurrent writers are blocked until all memtable insertions
have completed and the sequence number has been advanced, to preserve
linearizability.

My test config is "db_bench -benchmarks=fillrandom -threads=$T
-batch_size=1 -memtablerep=skip_list -value_size=100 --num=1000000/$T
-level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999
-disable_auto_compactions --max_write_buffer_number=8
-max_background_flushes=8 --disable_wal --write_buffer_size=160000000
--block_size=16384 --allow_concurrent_memtable_write" on a two-socket
Xeon E5-2660 @ 2.2Ghz with lots of memory and an SSD hard drive.  With 1
thread I get ~440Kops/sec.  Peak performance for 1 socket (numactl
-N1) is slightly more than 1Mops/sec, at 16 threads.  Peak performance
across both sockets happens at 30 threads, and is ~900Kops/sec, although
with fewer threads there is less performance loss when the system has
background work.

Test Plan:
1. concurrent stress tests for InlineSkipList and DynamicBloom
2. make clean; make check
3. make clean; DISABLE_JEMALLOC=1 make valgrind_check; valgrind db_bench
4. make clean; COMPILE_WITH_TSAN=1 make all check; db_bench
5. make clean; COMPILE_WITH_ASAN=1 make all check; db_bench
6. make clean; OPT=-DROCKSDB_LITE make check
7. verify no perf regressions when disabled

Reviewers: igor, sdong

Reviewed By: sdong

Subscribers: MarkCallaghan, IslamAbdelRahman, anthony, yhchiang, rven, sdong, guyg8, kradhakrishnan, dhruba

Differential Revision: https://reviews.facebook.net/D50589

Running manual compactions in parallel with other automatic or manual compactions in restricted cases

Summary:
This diff provides a framework for doing manual
compactions in parallel with other compactions. We now have a deque of manual compactions. We also pass manual compactions as an argument from RunManualCompactions down to
BackgroundCompactions, so that RunManualCompactions can be reentrant.
Parallelism is controlled by the two routines
ConflictingManualCompaction to allow/disallow new parallel/manual
compactions based on already existing ManualCompactions. In this diff, by default manual compactions still have to run exclusive of other compactions. However, by setting the compaction option, exclusive_manual_compaction to false, it is possible to run other compactions in parallel with a manual compaction. However, we are still restricted to one manual compaction per column family at a time. All of these restrictions will be relaxed in future diffs.
I will be adding more tests later.

Test Plan: Rocksdb regression + new tests + valgrind

Reviewers: igor, anthony, IslamAbdelRahman, kradhakrishnan, yhchiang, sdong

Reviewed By: sdong

Subscribers: yoshinorim, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D47973

  Mostly due to the fact that there are differences in sizes of int,long
  on 64 bit systems vs GNU.

 Fix warnings
 Take advantage of native snprintf on VS 15

* conversion from 'size_t' to 'type', by add static_cast

Tested:
* by build solution on Windows, Linux locally,
* run tests
* build CI system successful

Summary:
```
arc2 lint --everything
```

run the linter on the whole code repo to fix exisitng lint issues

Test Plan: make check -j64

Reviewers: sdong, rven, anthony, kradhakrishnan, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D50769

  in 64-bit.

  Currently, a signed off_t type is being used for the following
  interfaces for both offset and the length in bytes:
  * `Allocate`
  * `RangeSync`

  On Linux `off_t` is automatically either 32 or 64-bit depending on
  the platform. On Windows it is always a 32-bit signed long which
  limits file access and in particular space pre-allocation
  to effectively 2 Gb.

  Proposal is to replace off_t with uint64_t as a portable type
  always access files with 64-bit interfaces.

  May need to modify posix code but lack resources to test it.

  in 64-bit.

  Currently, a signed off_t type is being used for the following
  interfaces for both offset and the length in bytes:
  * `Allocate`
  * `RangeSync`

  On Linux `off_t` is automatically either 32 or 64-bit depending on
  the platform. On Windows it is always a 32-bit signed long which
  limits file access and in particular space pre-allocation
  to effectively 2 Gb.

  Proposal is to replace off_t with uint64_t as a portable type
  always access files with 64-bit interfaces.

  May need to modify posix code but lack resources to test it.

Summary: Run "make format" for some recent commits.

Test Plan: Build and run tests

Reviewers: IslamAbdelRahman

Reviewed By: IslamAbdelRahman

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D49707

  introduce a new DBOption random_access_max_buffer_size to limit
  the size of the random access buffer used for unbuffered access.
  Implement read ahead buffering when enabled.
  To that effect propagate compaction_readahead_size and the new option
  to the env options to make it available for the implementation.
  Add Hint() override so SetupForCompaction() call would call Hint()
  readahead can now be setup from both Hint() and EnableReadAhead()
  Add new option random_access_max_buffer_size support
  db_bench, options_helper to make it string parsable
  and the unit test.

Summary:
Give a name for every kill point, and allow users to disable some kill points based on prefixes. The kill points can be passed by db_stress through a command line paramter. This provides a way for users to boost the chance of triggering low frequency kill points
This allow follow up changes in crash test scripts to improve crash test coverage.

Test Plan:
Manually run db_stress with variable values of --kill_random_test and --kill_prefix_blacklist. Like this:
 --kill_random_test=2 --kill_prefix_blacklist=Posix,WritableFileWriter::Append,WritableFileWriter::WriteBuffered,WritableFileWriter::Sync

Reviewers: igor, kradhakrishnan, rven, IslamAbdelRahman, yhchiang

Reviewed By: yhchiang

Subscribers: leveldb, dhruba

Differential Revision: https://reviews.facebook.net/D48735

Summary:
  This mirrors  https://reviews.facebook.net/D45645
  Currently, mmap returns IOError when user tries to read
  data past the end of the file. This diff changes the behavior.
  Now, we return just the bytes that we can, and report the size
  we returned via a Slice result. This is consistent with non-mmap
  behavior and also pread() system call.