Summary:
Throughput: 46k tps in our sysbench settings (filling the details later)
The idea is to have the simplest change that gives us a reasonable boost
in 2PC throughput.
Major design changes:
1. The WAL file internal buffer is not flushed after each write. Instead
it is flushed before critical operations (WAL copy via fs) or when
FlushWAL is called by MySQL. Flushing the WAL buffer is also protected
via mutex_.
2. Use two sequence numbers: last seq, and last seq for write. Last seq
is the last visible sequence number for reads. Last seq for write is the
next sequence number that should be used to write to WAL/memtable. This
allows to have a memtable write be in parallel to WAL writes.
3. BatchGroup is not used for writes. This means that we can have
parallel writers which changes a major assumption in the code base. To
accommodate for that i) allow only 1 WriteImpl that intends to write to
memtable via mem_mutex_--which is fine since in 2PC almost all of the memtable writes
come via group commit phase which is serial anyway, ii) make all the
parts in the code base that assumed to be the only writer (via
EnterUnbatched) to also acquire mem_mutex_, iii) stat updates are
protected via a stat_mutex_.
Note: the first commit has the approach figured out but is not clean.
Submitting the PR anyway to get the early feedback on the approach. If
we are ok with the approach I will go ahead with this updates:
0) Rebase with Yi's pipelining changes
1) Currently batching is disabled by default to make sure that it will be
consistent with all unit tests. Will make this optional via a config.
2) A couple of unit tests are disabled. They need to be updated with the
serial commit of 2PC taken into account.
3) Replacing BatchGroup with mem_mutex_ got a bit ugly as it requires
releasing mutex_ beforehand (the same way EnterUnbatched does). This
needs to be cleaned up.
Closes https://github.com/facebook/rocksdb/pull/2345
Differential Revision: D5210732
Pulled By: maysamyabandeh
fbshipit-source-id: 78653bd95a35cd1e831e555e0e57bdfd695355a4
Summary:
This patch will block all tests (not including db_test) that don't compile / fail under ROCKSDB_LITE
Test Plan:
OPT=-DROCKSDB_LITE make db_compaction_filter_test -j64 &&
OPT=-DROCKSDB_LITE make db_compaction_test -j64 &&
OPT=-DROCKSDB_LITE make db_dynamic_level_test -j64 &&
OPT=-DROCKSDB_LITE make db_log_iter_test -j64 &&
OPT=-DROCKSDB_LITE make db_tailing_iter_test -j64 &&
OPT=-DROCKSDB_LITE make db_universal_compaction_test -j64 &&
OPT=-DROCKSDB_LITE make ldb_cmd_test -j64
make clean
make db_compaction_filter_test -j64 &&
make db_compaction_test -j64 &&
make db_dynamic_level_test -j64 &&
make db_log_iter_test -j64 &&
make db_tailing_iter_test -j64 &&
make db_universal_compaction_test -j64 &&
make ldb_cmd_test -j64
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48723
Summary:
As part of tech debt week, we are cleaning up dependencies.
This diff moves db_test_util.[h,cc] from util to db directory.
Test Plan: make check
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48543
Summary: Make TransactionLogIterator related tests from db_test.cc to db_log_iter_test.cc
Test Plan:
db_test
db_log_iter_test
Reviewers: sdong, IslamAbdelRahman, igor, anthony
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D42045
Siying Dong