Commit Graph

313 Commits

Author SHA1 Message Date
Lei Jin 9b0f7ffa1c rename version_set options_ to db_options_ to avoid confusion
Summary: as title

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23007
2014-09-08 15:25:01 -07:00
Lei Jin 048560a642 reduce references to cfd->options() in DBImpl
Summary:
I found it is almost impossible to get rid of this function in a single
batch. I will take a step by step approach

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22995
2014-09-08 15:04:34 -07:00
Igor Canadi a2bb7c3c33 Push- instead of pull-model for managing Write stalls
Summary:
Introducing WriteController, which is a source of truth about per-DB write delays. Let's define an DB epoch as a period where there are no flushes and compactions (i.e. new epoch is started when flush or compaction finishes). Each epoch can either:
* proceed with all writes without delay
* delay all writes by fixed time
* stop all writes

The three modes are recomputed at each epoch change (flush, compaction), rather than on every write (which is currently the case).

When we have a lot of column families, our current pull behavior adds a big overhead, since we need to loop over every column family for every write. With new push model, overhead on Write code-path is minimal.

This is just the start. Next step is to also take care of stalls introduced by slow memtable flushes. The final goal is to eliminate function MakeRoomForWrite(), which currently needs to be called for every column family by every write.

Test Plan: make check for now. I'll add some unit tests later. Also, perf test.

Reviewers: dhruba, yhchiang, MarkCallaghan, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22791
2014-09-08 11:20:25 -07:00
liuhuahang bb6ae0f80c fix more compile warnings
N/A

Change-Id: I5b6f9c70aea7d3f3489328834fed323d41106d9f
Signed-off-by: liuhuahang <liuhuahang@zerus.co>
2014-09-05 14:14:37 +08:00
Stanislau Hlebik 45a5e3ede0 Remove path with arena==nullptr from NewInternalIterator
Summary:
Simply code by removing code path which does not use Arena
from NewInternalIterator

Test Plan:
make all check
make valgrind_check

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22395
2014-09-04 17:40:41 -07:00
Yueh-Hsuan Chiang 570ba5aca8 Avoid retrying to read property block from a table when it does not exist.
Summary:
Avoid retrying to read property block from a table when it does not exist
in updating stats for compensating deletion entries.

In addition, ReadTableProperties() now returns Status::NotFound instead
of Status::Corruption when table properties does not exist in the file.

Test Plan:
make db_test -j32
export ROCKSDB_TESTS=CompactionDeleteionTrigger
./db_test

Reviewers: ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21867
2014-08-15 12:17:44 -07:00
Stanislau Hlebik 0c9dc9f8e0 Remove malloc from FormatFileNumber
Summary: Replace unnecessary malloc with stack allocation

Test Plan: make all check

Reviewers: sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21771
2014-08-13 11:57:40 -07:00
miguelportilla 93e6b5e9d9 Changes to support unity build:
* Script for building the unity.cc file via Makefile
* Unity executable Makefile target for testing builds
* Source code changes to fix compilation of unity build
2014-08-11 13:22:47 -04:00
sdong 1242bfcad7 Add DB property "rocksdb.estimate-table-readers-mem"
Summary:
Add a DB Property "rocksdb.estimate-table-readers-mem" to return estimated memory usage by all loaded table readers, other than allocated from block cache.

Refactor the property codes to allow getting property from a version, with DB mutex not acquired.

Test Plan: Add several checks of this new property in existing codes for various cases.

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: xjin, igor, leveldb

Differential Revision: https://reviews.facebook.net/D20733
2014-08-06 11:39:46 -07:00
Feng Zhu 1129921e9b logging_when_create_and_delete_manifest
Summary:
  1. logging when create and delete manifest file
  2. fix formating in table/format.cc

Test Plan:
  make all check
  run db_bench, track the LOG file.

Reviewers: ljin, yhchiang, igor, yufei.zhu, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D21009
2014-08-04 11:25:42 -07:00
Yueh-Hsuan Chiang 49ee5a4ac4 Fixed the crash when merge_operator is not properly set after reopen.
Summary:
Fixed the crash when merge_operator is not properly set after reopen
and added two test cases for this.

Test Plan:
make merge_test
./merge_test

Reviewers: igor, ljin, sdong

Reviewed By: sdong

Subscribers: benj, mvikjord, leveldb

Differential Revision: https://reviews.facebook.net/D20793
2014-07-30 17:24:36 -07:00
sdong f6784766db Add DB property estimated number of keys
Summary: Add a DB property of estimated number of live keys, by adding number of entries of all mem tables and all files, subtracted by all deletions in all files.

Test Plan: Add the case in unit tests

Reviewers: hobbymanyp, ljin

Reviewed By: ljin

Subscribers: MarkCallaghan, yoshinorim, leveldb, igor, dhruba

Differential Revision: https://reviews.facebook.net/D20631
2014-07-28 15:27:58 -07:00
Lei Jin 40fa8a4cd5 make statistics forward-able
Summary:
Make StatisticsImpl being able to forward stats to provided statistics
implementation. The main purpose is to allow us to collect internal
stats in the future even when user supplies custom statistics
implementation. It avoids intrumenting 2 sets of stats collection code.
One immediate use case is tuning advisor, which needs to collect some
internal stats, users may not be interested.

Test Plan:
ran db_bench and see stats show up at the end of run
Will run make all check since some tests rely on statistics

Reviewers: yhchiang, sdong, igor

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D20145
2014-07-28 12:05:36 -07:00
Yueh-Hsuan Chiang 6480717a26 Fixed compaction-related errors where number of input levels are hard-coded.
Summary:
Fixed compaction-related errors where number of input levels are hard-coded.
It's a bug found in compaction branch.
This diff will be pushed into master.

Test Plan:
export ROCKSDB_TESTS=Compact
make db_test -j32
./db_test
also passed the tests in compaction branch

Reviewers: igor, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D20577
2014-07-24 17:06:00 -07:00
sdong f6b7e1ed1a Allow user to specify DB path of output file of manual compaction
Summary: Add a parameter path_id to DB::CompactRange(), to indicate where the output file should be placed to.

Test Plan: add a unit test

Reviewers: yhchiang, ljin

Reviewed By: ljin

Subscribers: xjin, igor, dhruba, MarkCallaghan, leveldb

Differential Revision: https://reviews.facebook.net/D20085
2014-07-21 19:06:00 -07:00
Yueh-Hsuan Chiang 052ddbe0e2 Add MaxInputLevel() to CompactionPicker
Summary:
Having if-then branch for different compaction strategies is considered
hacky and make CompactionPicker less pluggable.  This diff removes two
of such if-then branches in version_set.cc by adding MaxInputLevel() to
CompactionPicker.

    // Given the current number of levels, returns the lowest allowed level
    // for compaction input.
    virtual int MaxInputLevel(int current_num_levels) const;

Test Plan:
make db_test
export ROCKSDB_TESTS=Compaction
./db_test

Reviewers: igor, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19971
2014-07-17 18:01:04 -07:00
Radheshyam Balasundaram 0d57e3ad7d Guarding files_ attribute with #ifndef NDEBUG guard in FilePicker class.
Summary: Adding guards to files_ attribute of FilePicker class. This attribute is used only in DEBUG mode. This fixes build of static_lib in mac.

Test Plan:
make static_lib in mac
make check all in devserver

Reviewers: ljin, igor, sdong

Reviewed By: sdong

Differential Revision: https://reviews.facebook.net/D20163
2014-07-17 15:07:05 -07:00
Yueh-Hsuan Chiang 296e340753 Add struct CompactionInputFiles to manage compaction input files.
Summary: Add struct CompactionInputFiles to manage compaction input files.

Test Plan:
export ROCKSDB_TESTS=Compact
make db_test
./db_test

Reviewers: ljin, igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D20061
2014-07-16 18:12:17 -07:00
Radheshyam Balasundaram 0418e66e2a Refactoring Version::Get()
Summary: Refactoring Version::Get() method to move file picker logic to a separate class.

Test Plan: make check all

Reviewers: igor, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19713
2014-07-16 13:33:02 -07:00
Feng Zhu c11d604ab3 store file_indexer info in sequential memory
Summary:
  use arena to allocate space for next_level_index_ and level_rb_
  Thus increasing data locality and make Version::Get faster.

Benchmark detail
Base version: commit d2a727c182

command used:
./db_bench --db=/mnt/db/rocksdb --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_type=none --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=2097152 --max_bytes_for_level_base=1073741824 --disable_wal=0 --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=fillseq, readrandom,readrandom,readrandom --use_existing_db=0 --num=52428800 --threads=1

Result:
cpu running percentage:
Version::Get, improved from 7.98% to 7.42%
FileIndexer::GetNextLevelIndex, improved from 1.18% to 0.68%.

Test Plan:
  make all check

Reviewers: ljin, haobo, yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba, igor

Differential Revision: https://reviews.facebook.net/D19845
2014-07-16 11:21:30 -07:00
sdong 0abaed2e08 Support multiple DB directories in universal compaction style
Summary:
This patch adds a target size parameter in options.db_paths and universal compaction will base it to determine which DB path to place a new file.
Level-style stays the same.

Test Plan: Add new unit tests

Reviewers: ljin, yhchiang

Reviewed By: yhchiang

Subscribers: MarkCallaghan, dhruba, igor, leveldb

Differential Revision: https://reviews.facebook.net/D19869
2014-07-15 12:06:28 -07:00
Feng Zhu 178fd6f9db use FileLevel in LevelFileNumIterator
Summary:
  Use FileLevel in LevelFileNumIterator, thus use new version of findFile.
  Old version of findFile function is deleted.
  Write a function in version_set.cc to generate FileLevel from files_.
  Add GenerateFileLevelTest in version_set_test.cc

Test Plan:
  make all check

Reviewers: ljin, haobo, yhchiang, sdong

Reviewed By: sdong

Subscribers: igor, dhruba

Differential Revision: https://reviews.facebook.net/D19659
2014-07-11 12:52:41 -07:00
Feng Zhu f697cad15c create compressed_levels_ in Version, allocate its space using arena. Make Version::Get, Version::FindFile faster
Summary:
    Define CompressedFileMetaData that just contains fd, smallest_slice, largest_slice. Create compressed_levels_ in Version, the space is allocated using arena
    Thus increase the file meta data locality, speed up "Get" and "FindFile"

    benchmark with in-memory tmpfs, could have 4% improvement under "random read" and 2% improvement under "read while writing"

benchmark command:
./db_bench --db=/mnt/db/rocksdb --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_type=none --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=33554432 --max_bytes_for_level_base=1073741824 --disable_wal=0 --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=readwhilewriting,readwhilewriting,readwhilewriting --use_existing_db=1 --num=52428800 --threads=1 —writes_per_second=81920

Read Random:
From 1.8363 ms/op, improve to 1.7587 ms/op.
Read while writing:
From 2.985 ms/op, improve to 2.924 ms/op.

Test Plan:
    make all check

Reviewers: ljin, haobo, yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba, igor

Differential Revision: https://reviews.facebook.net/D19419
2014-07-09 22:14:39 -07:00
Yueh-Hsuan Chiang 70828557ef Some fixes on size compensation logic for deletion entry in compaction
Summary:
This patch include two fixes:
1. newly created Version will now takes the aggregated stats for average-value-size from the latest Version.
2. compensated size of a file is now computed only for newly created / loaded file, this addresses the issue where files are already sorted by their compensated file size but might sometimes observe some out-of-order due to later update on compensated file size.

Test Plan:
export ROCKSDB_TESTS=CompactionDele
./db_test

Reviewers: ljin, igor, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19557
2014-07-09 12:46:08 -07:00
Igor Canadi 4203431e71 Fix mac os compile error 2014-07-03 23:03:24 +02:00
sdong 2459f7ec4e Support Multiple DB paths (without having an interface to expose to users)
Summary:
In this patch, we allow RocksDB to support multiple DB paths internally.
No user interface is supported yet so this patch is silent to users.

Test Plan: make all check

Reviewers: igor, haobo, ljin, yhchiang

Reviewed By: yhchiang

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D18921
2014-07-02 21:14:44 -07:00
Igor Canadi a2e0d890ed No need for files_by_size_ in universal compaction
Summary: files_by_size_ is sorted by time in case of universal compaction. However, Version::files_ is also sorted by time. So no need for files_by_size_

Test Plan:
1) make check with the change
2) make check with `assert(last_index == c->input_version_->files_[level].size() - 1);` in compaction picker

Reviewers: dhruba, haobo, yhchiang, sdong, ljin

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19125
2014-07-01 08:55:04 +02:00
Yueh-Hsuan Chiang e813f5b6d9 Allow compaction to reclaim storage more effectively.
Summary:
This diff allows compaction to reclaim storage more effectively.
In the current design, compactions are mainly triggered based on
the file sizes.  However, since deletion entries does not have
value, files which have many deletion entries are less likely
to be compacted.  As a result, it may took a while to make
deletion entries to be compacted.

This diff address issue by compensating the size of deletion
entries during compaction process: the size of each deletion
entry in the compaction process is augmented by 2x average
value size.  The diff applies to both leveled and universal
compacitons.

Test Plan:
develop CompactionDeletionTrigger
make db_test
./db_test

Reviewers: haobo, igor, ljin, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19029
2014-06-24 16:37:06 -06:00
Igor Canadi d4a8423334 Remove seek compaction
Summary:
As discussed in our internal group, we don't get much use of seek compaction at the moment, while it's making code more complicated and slower in some cases.

This diff removes seek compaction and (hopefully) all code that was introduced to support seek compaction.

There is one test case that relied on didIO information. I'll try to find another way to implement it.

Test Plan: make check

Reviewers: sdong, haobo, yhchiang, ljin, dhruba

Reviewed By: ljin

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19161
2014-06-20 10:23:02 +02:00
Igor Canadi 107e08baa7 Use same sorting for all level 0 files
Summary:
We decided that one of the long term goals is to unify level and universal compaction.

As a small first step, I'm unifying level 0 sorting methods.

Previously, we used to sort level 0 files in level compaction by file number and in universal compaction by sequence number.

But it turns out that in level compaction, sorting by file number is exactly the same as sorting by sequence number.

Test Plan:
Ran make check with bunch of asserts to verify the sorting order is exactly the same.
Also, make check with this patch

Reviewers: haobo, yhchiang, ljin, dhruba, sdong

Reviewed By: sdong

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D19131
2014-06-20 09:12:14 +02:00
sdong cadc1adffa Refactor: group metadata needed to open an SST file to a separate copyable struct
Summary:
We added multiple fields to FileMetaData recently and are planning to add more.
This refactoring separate the minimum information for accessing the file. This object is copyable (FileMetaData is not copyable since the ref counter). I hope this refactoring can enable further improvements:

(1) use it to design a more efficient data structure to speed up read queries.
(2) in the future, when we add information of storage level, we can easily do the encoding, instead of enlarge this structure, which might expand memory work set for file meta data.

The definition is same as current EncodedFileMetaData used in two level iterator, so now the logic in two level iterator is easier to understand.

Test Plan: make all check

Reviewers: haobo, igor, ljin

Reviewed By: ljin

Subscribers: leveldb, dhruba, yhchiang

Differential Revision: https://reviews.facebook.net/D18933
2014-06-16 16:10:52 -07:00
sdong 983c93d731 VersionSet::Get(): Bring back the logic of skipping key range check when there are <=3 level 0 files
Summary:
https://reviews.facebook.net/D17205 removed the logic of skipping file key range check when there are less than 3 level 0 files. This patch brings it back.

Other than that, add another small optimization to avoid to check all the levels if most higher levels don't have any file.

Test Plan: make all check

Reviewers: ljin

Reviewed By: ljin

Subscribers: yhchiang, igor, haobo, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D19035
2014-06-13 15:51:44 -07:00
Lei Jin c83b085770 prefetch bloom filter data block for L0 files
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
2014-06-12 10:06:18 -07:00
sdong df9069d23f In DB::NewIterator(), try to allocate the whole iterator tree in an arena
Summary:
In this patch, try to allocate the whole iterator tree starting from DBIter from an arena
1. ArenaWrappedDBIter is created when serves as the entry point of an iterator tree, with an arena in it.
2. Add an option to create iterator from arena for following iterators: DBIter, MergingIterator, MemtableIterator, all mem table's iterators, all table reader's iterators and two level iterator.
3. MergeIteratorBuilder is created to incrementally build the tree of internal iterators. It is passed to mem table list and version set and add iterators to it.

Limitations:
(1) Only DB::NewIterator() without tailing uses the arena. Other cases, including readonly DB and compactions are still from malloc
(2) Two level iterator itself is allocated in arena, but not iterators inside it.

Test Plan: make all check

Reviewers: ljin, haobo

Reviewed By: haobo

Subscribers: leveldb, dhruba, yhchiang, igor

Differential Revision: https://reviews.facebook.net/D18513
2014-06-02 17:44:57 -07:00
Igor Canadi 6de6a06631 FIFO compaction style
Summary:
Introducing new compaction style -- FIFO.

FIFO compaction style has write amplification of 1 (+1 for WAL) and it deletes the oldest files when the total DB size exceeds pre-configured values.

FIFO compaction style is suited for storing high-frequency event logs.

Test Plan: Added a unit test

Reviewers: dhruba, haobo, sdong

Reviewed By: dhruba

Subscribers: alberts, leveldb

Differential Revision: https://reviews.facebook.net/D18765
2014-05-21 11:43:35 -07:00
Igor Canadi f4574449e9 Clean up compaction logging
Summary: Cleaned up compaction logging a little bit. Now file sizes are easier to read. Also, removed the trailing space.

Test Plan:
verified that i'm happy with logging output:

        files_size[#33(seq=101,sz=98KB,0) #31(seq=81,sz=159KB,0) #26(seq=0,sz=637KB,0)]

Reviewers: sdong, haobo, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18549
2014-05-14 12:13:50 -07:00
sdong 9efbd85ac9 fsync directory after creating current file in NewDB()
Summary: One of our users reported current file corruption. The machine was rebooted during the time. This is the only think I can think of which could cause current file corruption. Just add this paranoid check.

Test Plan: make all check

Reviewers: haobo, igor

Reviewed By: haobo

CC: yhchiang, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D18495
2014-05-06 17:51:33 -07:00
Igor Canadi 096f5be0ed Put column family information in LiveFileMetaData
Summary: As summary

Test Plan: compiles :)

Reviewers: dhruba, haobo, sdong, yhchiang

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D18405
2014-04-30 16:24:52 -04:00
Lei Jin ccaca59bee avoid calling FindFile twice in TwoLevelIterator for PlainTable
Summary:
this is to reclaim the regression introduced in
https://reviews.facebook.net/D17853

Test Plan: make all check

Reviewers: igor, haobo, sdong, dhruba, yhchiang

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17985
2014-04-25 12:23:07 -07:00
Lei Jin d642c60bdc Check PrefixMayMatch on Seek()
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
2014-04-25 12:22:23 -07:00
Lei Jin 3995e801ab kill ReadOptions.prefix and .prefix_seek
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
2014-04-25 12:21:34 -07:00
Igor Canadi ad3cd39ccd Column family logging
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
2014-04-25 09:51:16 -04:00
Lei Jin 0f2d768191 hints for narrowing down FindFile range and avoiding checking unrelevant L0 files
Summary:
The file tree structure in Version is prebuilt and the range of each file is known.
On the Get() code path, we do binary search in FindFile() by comparing
target key with each file's largest key and also check the range for each L0 file.
With some pre-calculated knowledge, each key comparision that has been done can serve
as a hint to narrow down further searches:
(1) If a key falls within a L0 file's range, we can safely skip the next
file if its range does not overlap with the current one.
(2) If a key falls within a file's range in level L0 - Ln-1, we should only
need to binary search in the next level for files that overlap with the current one.

(1) will be able to skip some files depending one the key distribution.
(2) can greatly reduce the range of binary search, especially for bottom
levels, given that one file most likely only overlaps with N files from
the level below (where N is max_bytes_for_level_multiplier). So on level
L, we will only look at ~N files instead of N^L files.

Some inital results: measured with 500M key DB, when write is light (10k/s = 1.2M/s), this
improves QPS ~7% on top of blocked bloom. When write is heavier (80k/s =
9.6M/s), it gives us ~13% improvement.

Test Plan: make all check

Reviewers: haobo, igor, dhruba, sdong, yhchiang

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17205
2014-04-21 09:10:12 -07:00
sdong 651792251a Fix bugs introduced by D17961
Summary:
D17961 has two bugs:
(1) two level iterator fails to populate FileMetaData.table_reader, causing performance regression.
(2) table cache handle the !status.ok() case in the wrong place, causing seg fault which shouldn't happen.

Test Plan: make all check

Reviewers: ljin, igor, haobo

Reviewed By: ljin

CC: yhchiang, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D17991
2014-04-17 17:25:28 -07:00
sdong fa430bfd04 Minimize accessing multiple objects in Version::Get()
Summary:
One of our profilings shows that Version::Get() sometimes is slow when getting pointer of user comparators or other global objects. In this patch:
(1) we keep pointers of immutable objects in Version to avoid accesses them though option objects or cfd objects
(2) table_reader is directly cached in FileMetaData so that table cache don't have to go through handle first to fetch it
(3) If level 0 has less than 3 files, skip the filtering logic based on SST tables' key range. Smallest and largest key are stored in separated memory locations, which has potential cache misses

Test Plan: make all check

Reviewers: haobo, ljin

Reviewed By: haobo

CC: igor, yhchiang, nkg-, leveldb

Differential Revision: https://reviews.facebook.net/D17739
2014-04-17 14:14:00 -07:00
Igor Canadi 588bca2020 RocksDBLite
Summary:
Introducing RocksDBLite! Removes all the non-essential features and reduces the binary size. This effort should help our adoption on mobile.

Binary size when compiling for IOS (`TARGET_OS=IOS m static_lib`) is down to 9MB from 15MB (without stripping)

Test Plan: compiles :)

Reviewers: dhruba, haobo, ljin, sdong, yhchiang

Reviewed By: yhchiang

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17835
2014-04-15 13:39:26 -07:00
Igor Canadi e6acb874cd Don't roll empty logs
Summary:
With multiple column families, especially when manual Flush is executed, we might roll the log file, although the current log file is empty (no data has been written to the log).

After the diff, we won't create new log file if current is empty.

Next, I will write an algorithm that will flush column families that reference old log files (i.e., that weren't flushed in a while)

Test Plan: Added an unit test. Confirmed that unit test failes in master

Reviewers: dhruba, haobo, ljin, sdong

Reviewed By: ljin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17631
2014-04-15 09:57:25 -07:00
Igor Canadi 2014915d32 Fix ASAN issue 2014-04-09 10:38:05 -07:00
Igor Canadi b947fdc89d Column family support for DB::OpenForReadOnly()
Summary: When opening DB in read-only mode, client can choose to only specify a subset of column families ("default" column family can't be omitted, though)

Test Plan: added a unit test in column_family_test

Reviewers: haobo, sdong, ljin, dhruba

Reviewed By: haobo

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17565
2014-04-09 09:56:17 -07:00
Igor Canadi 5b345b76cb Remove env_ from MergingIterator
Summary: env_ is not used. Compiling for iOS complains.

Test Plan: compiles now

Reviewers: ljin, haobo, sdong, dhruba

Reviewed By: ljin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17589
2014-04-08 13:40:42 -07:00