Summary:
= Major Changes =
* Add a new mem-table representation, HashCuckooRep, which is based cuckoo hash.
Cuckoo hash uses multiple hash functions. This allows each key to have multiple
possible locations in the mem-table.
- Put: When insert a key, it will try to find whether one of its possible
locations is vacant and store the key. If none of its possible
locations are available, then it will kick out a victim key and
store at that location. The kicked-out victim key will then be
stored at a vacant space of its possible locations or kick-out
another victim. In this diff, the kick-out path (known as
cuckoo-path) is found using BFS, which guarantees to be the shortest.
- Get: Simply tries all possible locations of a key --- this guarantees
worst-case constant time complexity.
- Time complexity: O(1) for Get, and average O(1) for Put if the
fullness of the mem-table is below 80%.
- Default using two hash functions, the number of hash functions used
by the cuckoo-hash may dynamically increase if it fails to find a
short-enough kick-out path.
- Currently, HashCuckooRep does not support iteration and snapshots,
as our current main purpose of this is to optimize point access.
= Minor Changes =
* Add IsSnapshotSupported() to DB to indicate whether the current DB
supports snapshots. If it returns false, then DB::GetSnapshot() will
always return nullptr.
Test Plan:
Run existing tests. Will develop a test specifically for cuckoo hash in
the next diff.
Reviewers: sdong, haobo
Reviewed By: sdong
CC: leveldb, dhruba, igor
Differential Revision: https://reviews.facebook.net/D16155
Summary:
ReadFirstRecord() reads the actual log file from disk on every call. This diff introduces a cache layer on top of ReadFirstRecord(), which should significantly speed up repeated calls to GetUpdatesSince().
I also cleaned up some stuff, but the whole TransactionLogIterator could use some refactoring, especially if we see increased usage.
Test Plan: make check
Reviewers: haobo, sdong, dhruba
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18387
Summary:
This enables user to add a TTL column family to normal DB.
Next step should be to expand StackableDB and create StackableColumnFamily, such that users can for example add geo-spatial column families to normal DB.
Test Plan: added a test
Reviewers: dhruba, haobo, ljin
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18201
Summary:
When TransactionLogIterator comes to EOF, it calls UnmarkEOF and continues reading. However, if glibc cached the EOF status of the file, it will get EOF again, even though the new data might have been written to it.
This has been causing errors in Mac OS.
Test Plan: test passes, was failing before
Reviewers: dhruba, haobo, sdong
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18381
Summary: Read-only BackupEngine can connect to the same backup directory that is already running BackupEngine. That enables some interesting use-cases (i.e. restoring replica from primary's backup directory)
Test Plan: added a unit test
Reviewers: dhruba, haobo, ljin
Reviewed By: ljin
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18297
Summary:
As a follow-up diff for https://reviews.facebook.net/D17805, add
optimization to check PrefixMayMatch on Seek()
Test Plan: make all check
Reviewers: igor, haobo, sdong, yhchiang, dhruba
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D17853
Summary:
also add an override option total_order_iteration if you want to use full
iterator with prefix_extractor
Test Plan: make all check
Reviewers: igor, haobo, sdong, yhchiang
Reviewed By: haobo
CC: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D17805
Summary: As summary. Add two autovectors that get filled up in MakeRoomForWrite and they get deleted outside of mutex
Test Plan: make check
Reviewers: dhruba, haobo, ljin, sdong
Reviewed By: ljin
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18249
Summary:
Now that we have column families involved, we need to add extra context to every log message. They now start with "[column family name] log message"
Also added some logging that I think would be useful, like level summary after every flush (I often needed that when going through the logs).
Test Plan: make check + ran db_bench to confirm I'm happy with log output
Reviewers: dhruba, haobo, ljin, yhchiang, sdong
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18303
Summary:
Now this gives us the real deal stack trace:
Assertion failed: (false), function GetProperty, file db/db_impl.cc, line 4072.
Received signal 6 (Abort trap: 6)
#0 0x7fff57ce39b9
#1 abort (in libsystem_c.dylib) + 125
#2 basename (in libsystem_c.dylib) + 0
#3 rocksdb::DBImpl::GetProperty(rocksdb::ColumnFamilyHandle*, rocksdb::Slice const&, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >*) (in db_test) (db_impl.cc:4072)
#4 rocksdb::_Test_Empty::_Run() (in db_test) (testharness.h:68)
#5 rocksdb::_Test_Empty::_RunIt() (in db_test) (db_test.cc:1005)
#6 rocksdb::test::RunAllTests() (in db_test) (testharness.cc:60)
#7 main (in db_test) (db_test.cc:6697)
#8 start (in libdyld.dylib) + 1
Test Plan: added artificial assert, saw great stack trace
Reviewers: haobo, dhruba, ljin
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18309
Summary:
* Add filluniquerandom
* Add readseq, implemented using iterator.
* Realize most command-line-arguments from db_bench.cc (70+).
* Some code are commented out as some of the options in Options
not yet have Java bindings.
* Add default option to DbBenchmark.
* RocksDB will now take the ownership of all c++ raw-pointers from Options, which includes a c++ raw-pointer for Filter.
Test Plan: ./jdb_bench.sh --db=/tmp/rocksjava-bench/db --num_levels=6 --key_size=20 --prefix_size=20 --keys_per_prefix=0 --value_size=100 --block_size=4096 --cache_size=17179869184 --cache_numshardbits=6 --compression_ratio=1 --min_level_to_compress=-1 --disable_seek_compaction=1 --hard_rate_limit=2 --write_buffer_size=134217728 --max_write_buffer_number=2 --level0_file_num_compaction_trigger=8 --target_file_size_base=134217728 --max_bytes_for_level_base=1073741824 --disable_wal=0 --wal_dir=/tmp/rocksjava-bench/wal --sync=0 --disable_data_sync=1 --verify_checksum=1 --delete_obsolete_files_period_micros=314572800 --max_grandparent_overlap_factor=10 --max_background_compactions=4 --max_background_flushes=0 --level0_slowdown_writes_trigger=16 --level0_stop_writes_trigger=24 --statistics=0 --stats_per_interval=0 --stats_interval=1048576 --histogram=0 --use_plain_table=1 --open_files=-1 --mmap_read=1 --mmap_write=0 --memtablerep=prefix_hash --bloom_bits=10 --bloom_locality=1 --perf_level=0 --benchmarks=filluniquerandom,readseq,readrandom --use_existing_db=0 --threads=4
Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18267
Summary:
I'm getting lots of e-mails with CompactionInputErrorParanoid failing. Most recent example early morning today was: http://ci-builds.fb.com/job/rocksdb_valgrind/562/consoleFull
I'm putting a stop to these e-mails. I investigated why the test is flakey and it turns out it's because of non-determinsim of compaction scheduling. If there is a compaction after the last flush, CorruptFile will corrupt the compacted file instead of file at level 0 (as it assumes). That makes `Check(9, 9)` fail big time.
I also saw some errors with table file getting outputed to >= 1 levels instead of 0. Also fixed that.
Test Plan: Ran corruption_test 100 times without a failure. Previously it usually failed at 10th occurrence.
Reviewers: dhruba, haobo, ljin
Reviewed By: ljin
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18285
Summary: Sometimes, our tests fail because of normal `assert` call. It would be helpful to see stack trace in that case, too.
Test Plan: Added `assert(false)` and verified it prints out stack trace
Reviewers: haobo, dhruba, sdong, ljin, yhchiang
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18291
Summary:
Currently, whenever DB Verification fails we bail out by calling `exit(1)`. This is kind of bad since it causes unclean shutdown and spew of error log messages like:
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
05:03:27 pthread lock: Invalid argument
This diff adds a new parameter that is set to true when verification fails. It can then use the parameter to bail out safely.
Test Plan: Casued artificail failure. Verified that exit was clean.
Reviewers: dhruba, haobo, ljin
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18243
Summary:
Add Java bindings and Java tests for 30+ rocksdb::Options. Codes are
machine-genearted based on include/rocksdb/options.h with manual-polishment.
Test Plan:
make rocksdbjava
make jtest
Reviewers: haobo, dhruba, sdong, ankgup87, rsumbaly, swapnilghike, zzbennett
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18273
Summary: IterKey set buffer_size_ to a wrong initial value, causing it to always allocate values from heap instead of stack if the key size is smaller. Fix it.
Test Plan: make all check
Reviewers: haobo, ljin
Reviewed By: haobo
CC: igor, dhruba, yhchiang, leveldb
Differential Revision: https://reviews.facebook.net/D18279
Summary: While debugging Mac-only issue with ThreadLocalPtr, this was very useful. Let's print out stack trace in MAC OS, too.
Test Plan: Verified that somewhat useful stack trace was generated on mac. Will run PrintStack() on linux, too.
Reviewers: ljin, haobo
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D18189
Summary: In this patch, two new DB properties are defined: rocksdb.num-immutable-mem-table and rocksdb.num-entries-imm-mem-tables, from where number of entries in mem tables can be exposed to users
Test Plan:
Cover the codes in db_test
make all check
Reviewers: haobo, ljin, igor
Reviewed By: igor
CC: nkg-, igor, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D18207
Summary: Get rid of the devil. Probably won't impact anything on the perf side.
Test Plan: make all check
Reviewers: igor, haobo, sdong, yhchiang
Reviewed By: haobo
CC: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D18153
