Fix the selection of the fast CRC32 path in Ceph Luminous.
This ugly patch selectively adds the `-msse4.2` for compiling
`util/crc32c.cc` file when a building machine's toolchain had
successfully compiled a simple test program. The CXXFLAGS are
enriched even when `WITH_SSE42` is not set as, in Ceph, there
is no possibility to use the global switch because of lack of
proper run-time SSE4.2 check in other places IIUC.
Although the problem is fixed in `master` of RocksDB, the fix
cannot be backported because the CRC32-related stuff diverged
too much (`HAVE_POWER8`, `HAVE_PCLMUL`, `NO_THREEWAY_CRC32C`).
Use L1 size as estimate for L0 size in LevelCompactionBuilder::GetPathID
Summary:
Fix for [2461](https://github.com/facebook/rocksdb/issues/2461).
Problem: When using multiple db_paths setting with RocksDB, RocksDB incorrectly calculates the size of L1 in LevelCompactionBuilder::GetPathId.
max_bytes_for_level_base is used as L0 size and L1 size is calculated as (L0 size * max_bytes_for_level_multiplier). However, L1 size should be max_bytes_for_level_base.
Solution: Use max_bytes_for_level_base as L1 size. Also, use L1 size as the estimated size of L0.
Closes https://github.com/facebook/rocksdb/pull/2903
Summary:
if we enable SSE42 globally when compiling the tree for preparing a
portable binary, which could be running on CPU w/o SSE42 instructions
even the GCC on the building host is able to emit SSE42 code, this leads
to illegal instruction errors on machines not supporting SSE42. to solve
this problem, crc32 detects the supported instruction at runtime, and
selects the supported CRC32 implementation according to the result of
`cpuid`. but intrinics like "_mm_crc32_u64()" will not be available
unless the "target" machine is appropriately specified in the command
line, like "-msse42", or using the "target" attribute.
we could pass "-msse42" only when compiling crc32c.cc, and allow the
compiler to generate the SSE42 instructions, but we are still at the
risk of executing illegal instructions on machines does not support
SSE42 if the compiler emits code that is not guarded by our runtime
detection. and we need to do the change in both Makefile and CMakefile.
or, we can use GCC's "target" attribute to enable the machine specific
instructions on certain function. in this way, we have finer grained
control of the used "target". and no need to change the makefiles. so
we don't need to duplicate the changes on both makefile and cmake as
the previous approach.
this problem surfaces when preparing a package for GNU/Linux distribution,
and we only applies to optimization for SSE42, so using a feature
only available on GCC/Clang is not that formidable.
Closes https://github.com/facebook/rocksdb/pull/2807
Andrew Kryczka [Wed, 26 Apr 2017 22:19:50 +0000 (15:19 -0700)]
Add user stats Reset API
Summary:
It resets all the ticker and histogram stats to zero. Needed to change the locking a bit since Reset() is the only operation that manipulates multiple tickers/histograms together, and that operation should be seen as atomic by other operations that access tickers/histograms.
Closes https://github.com/facebook/rocksdb/pull/2213
add prefetch to PosixRandomAccessFile in buffered io
Summary:
Every time after a compaction/flush finish, we issue user reads to put the table into block cache which includes a couple of IO that read footer, index blocks, meta block, etc. So we implement Prefetch here to reduce IO.
Closes https://github.com/facebook/rocksdb/pull/2196
Andrew Kryczka [Wed, 26 Apr 2017 21:18:58 +0000 (14:18 -0700)]
Extract statistics tests into separate file
Summary:
I'm going to add more DB tests for statistics as currently we have very few. I started a file dedicated to this purpose and moved the existing stats-specific tests there.
Closes https://github.com/facebook/rocksdb/pull/2211
Andrew Kryczka [Mon, 24 Apr 2017 21:57:27 +0000 (14:57 -0700)]
Reunite checkpoint and backup core logic
Summary:
These code paths forked when checkpoint was introduced by copy/pasting the core backup logic. Over time they diverged and bug fixes were sometimes applied to one but not the other (like fix to include all relevant WALs for 2PC), or it required extra effort to fix both (like fix to forge CURRENT file). This diff reunites the code paths by extracting the core logic into a function, CreateCustomCheckpoint(), that is customizable via callbacks to implement both checkpoint and backup.
Related changes:
- flush_before_backup is now forcibly enabled when 2PC is enabled
- Extracted CheckpointImpl class definition into a header file. This is so the function, CreateCustomCheckpoint(), can be called by internal rocksdb code but not exposed to users.
- Implemented more functions in DummyDB/DummyLogFile (in backupable_db_test.cc) that are used by CreateCustomCheckpoint().
Closes https://github.com/facebook/rocksdb/pull/1932