Summary:
Bloomfilter and hashskiplist's buckets_ allocated by memtable's arena
DynamicBloom: pass arena via constructor, allocate space in SetTotalBits
HashSkipListRep: allocate space of buckets_ using arena.
do not delete it in deconstructor because arena would take care of it.
Several test files are changed.
Test Plan:
make all check
Reviewers: ljin, haobo, yhchiang, sdong
Reviewed By: sdong
Subscribers: igor, dhruba
Differential Revision: https://reviews.facebook.net/D19335
Summary: as title
Test Plan:
db_bench
the initial result is very promising. I will post results of complete
runs
Reviewers: dhruba, haobo, sdong, igor
Reviewed By: sdong
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D18867
Summary:
Clean PlainTableReader's data structures:
(1) inline bloom_ (in order to do this, change DynamicBloom to allow lazy initialization)
(2) remove some variables only used when initialization from the class
(3) put variables not used in normal read code paths to the end of the class and reference prefix_extractor directly
(4) make Options a reference.
Test Plan: make all check
Reviewers: haobo, ljin
Reviewed By: ljin
Subscribers: igor, yhchiang, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D18891
Summary:
This patch changes meaning of options.bloom_locality: 0 means disable cache line optimization and any positive number means use CACHE_LINE_SIZE as block size (the previous behavior is the block size will be CACHE_LINE_SIZE*options.bloom_locality). By doing it, the divide operations inside a block can be replaced by a shift.
Performance is improved:
https://reviews.facebook.net/P471
Also, improve the basic algorithm in two ways:
(1) make sure num of blocks is an odd number
(2) rotate bytes after every probe in locality mode. Since the divider is 2^n, unless doing it, we are never able to use all the bits.
Improvements of false positive: https://reviews.facebook.net/P459
Test Plan: make all check
Reviewers: ljin, haobo
Reviewed By: haobo
Subscribers: dhruba, yhchiang, igor, leveldb
Differential Revision: https://reviews.facebook.net/D18843
Summary:
TLB page allocation errors are now logged to info logs, instead of stderr.
In order to do that, mem table rep's factory functions take a info logger now.
Test Plan: make all check
Reviewers: haobo, igor, yhchiang
Reviewed By: yhchiang
CC: leveldb, yhchiang, dhruba
Differential Revision: https://reviews.facebook.net/D18471
Summary: Add an option to allocate a piece of memory from huge page TLB. Add options to trigger it in dynamic bloom, plain table indexes andhash linked list hash table.
Test Plan: make all check
Reviewers: haobo, ljin
Reviewed By: haobo
CC: nkg-, dhruba, leveldb, igor, yhchiang
Differential Revision: https://reviews.facebook.net/D18357
Summary:
By constraining the probes within cache line(s), we can improve the
cache miss rate thus performance. This probably only makes sense for
in-memory workload so defaults the option to off.
Numbers and comparision can be found in wiki:
https://our.intern.facebook.com/intern/wiki/index.php/Ljin/rocksdb_perf/2014_03_17#Bloom_Filter_Study
Test Plan: benchmarked this change substantially. Will run make all check as well
Reviewers: haobo, igor, dhruba, sdong, yhchiang
Reviewed By: haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D17133
Summary:
In latest leaf's, MayContainHash() consistently consumes 5%~7% CPU usage.
I checked the code and did an experiment with/without inlining this method.
In release mode, with `1024 * 1024 * 256` bits and `1024 * 512` entries, both call 2^30 MayContainHash() with distinctive parameters.
As the result showed, this patch reduced the running time from 9.127 sec to 7.891 sec.
Test Plan: make check
Reviewers: sdong, haobo
CC: leveldb
Differential Revision: https://reviews.facebook.net/D15177
Summary:
Some changes to PlainTable format:
(1) support variable key length
(2) use user defined slice transformer to extract prefixes
(3) Run some test cases against PlainTable in db_test and table_test
Test Plan: test db_test
Reviewers: haobo, kailiu
CC: dhruba, igor, leveldb, nkg-
Differential Revision: https://reviews.facebook.net/D14457
Summary: as title
Test Plan: dynamic_bloom_test
Reviewers: dhruba, sdong, kailiu
CC: leveldb
Differential Revision: https://reviews.facebook.net/D14385
