Commit Graph

308 Commits

Author SHA1 Message Date
Dhruba Borthakur
3754f2f4ff A major bug that was not considering the compaction score of the n-1 level.
Summary:
The method Finalize() recomputes the compaction score of each
level and then sorts these score from largest to smallest. The
idea is that the level with the largest compaction score will
be a better candidate for compaction.  There are usually very
few levels, and a bubble sort code was used to sort these
compaction scores. There existed a bug in the sorting code that
skipped looking at the score for the n-1 level. This meant that
even if the compaction score of the n-1 level is large, it will
not be picked for compaction.

This patch fixes the bug and also introduces "asserts" in the
code to detect any possible inconsistencies caused by future bugs.

This bug existed in the very first code change that introduced
multi-threaded compaction to the leveldb code. That version of
code was committed on Oct 19th via
1ca0584345

Test Plan: make clean check OPT=-g

Reviewers: emayanke, sheki, MarkCallaghan

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6837
2012-11-20 15:44:21 -08:00
Dhruba Borthakur
dde70898a1 Fix asserts
Summary:
make check OPT=-g fails with the following assert.
==== Test DBTest.ApproximateSizes
db_test: db/version_set.cc:765: void leveldb::VersionSet::Builder::CheckConsistencyForDeletes(leveldb::VersionEdit*, int, int): Assertion `found' failed.

The assertion was that file #7 that was being deleted did not
preexists, but actualy it did pre-exist as shown in the manifest
dump shows below. The bug was that we did not check for file
existance at the same level.

*************************Edit[0] = VersionEdit {
  Comparator: leveldb.BytewiseComparator
}

*************************Edit[1] = VersionEdit {
  LogNumber: 8
  PrevLogNumber: 0
  NextFile: 9
  LastSeq: 80
  AddFile: 0 7 8005319 'key000000' @ 1 : 1 .. 'key000079' @ 80 : 1
}

*************************Edit[2] = VersionEdit {
  LogNumber: 8
  PrevLogNumber: 0
  NextFile: 13
  LastSeq: 80
  CompactPointer: 0 'key000079' @ 80 : 1
  DeleteFile: 0 7
  AddFile: 1 9 2101425 'key000000' @ 1 : 1 .. 'key000020' @ 21 : 1
  AddFile: 1 10 2101425 'key000021' @ 22 : 1 .. 'key000041' @ 42 : 1
  AddFile: 1 11 2101425 'key000042' @ 43 : 1 .. 'key000062' @ 63 : 1
  AddFile: 1 12 1701165 'key000063' @ 64 : 1 .. 'key000079' @ 80 : 1
}

Test Plan:

Reviewers:

CC:

Task ID: #

Blame Rev:
2012-11-19 14:51:22 -08:00
Dhruba Borthakur
48dafb2c59 Fix compilation error introduced by previous commit
7889e09455

Summary:
Fix compilation error introduced by previous commit
7889e09455

Test Plan:
make clean check
2012-11-19 12:16:45 -08:00
Dhruba Borthakur
7889e09455 Enhance manifest_dump to print each individual edit.
Summary:
The manifest file contains a series of edits. If the verbose
option is switched on, then print each individual edit in the
manifest file. This helps in debugging.

Test Plan: make clean manifest_dump

Reviewers: emayanke, sheki

Reviewed By: sheki

CC: leveldb

Differential Revision: https://reviews.facebook.net/D6807
2012-11-19 12:04:35 -08:00
Dhruba Borthakur
43d9a8225a Fix asserts so that "make check OPT=-g" works on performance branch
Summary:
Compilation used to fail with the error:
db/version_set.cc:1773: error: ‘number_of_files_to_sort_’ is not a member of ‘leveldb::VersionSet’

I created a new method called CheckConsistencyForDeletes() so that
all the high cost checking is done only when OPT=-g is specified.

I also fixed a bug in PickCompactionBySize that was triggered when
OPT=-g was switched on. The base_index in the compaction record
was not set correctly.

Test Plan: make check OPT=-g

Differential Revision: https://reviews.facebook.net/D6687
2012-11-13 10:40:52 -08:00
Dhruba Borthakur
95dda37858 Move filesize-based-sorting to outside the Mutex
Summary:
When a new version is created, we sort all the files at every
level based on their size. This is necessary because we want
to compact the largest file first. The sorting takes quite a
bit of CPU.

Moved the sorting code to be outside the mutex. Also, the
earlier code was sorting files at all levels but we do not
need to sort the highest-number level because those files
are never the cause of any compaction. To reduce sorting
costs, we sort only the first few files in each level
because it is likely that those are the only files in that
level that will be picked for compaction.

At steady state, I have seen that this patch increase
throughout from 1500 writes/sec to 1700 writes/sec at the
end of a 72 hour run. The cpu saving by not sorting the
last level was not distinctive in this test run because
there were only 100K files in the highest numbered level.
I expect the cpu saving to be significant when the number of
files is much higher.

This is mostly an early preview and not ready for rigorous review.

With this patch, the writs/sec is now bottlenecked not by the sorting code but by GetOverlappingInputs. I am working on a patch to optimize GetOverlappingInputs.

Test Plan: make check

Reviewers: MarkCallaghan, heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D6411
2012-11-07 15:39:44 -08:00
Dhruba Borthakur
8143062edd Merge branch 'master' into performance
Conflicts:
	db/db_impl.cc
	db/version_set.cc
	util/options.cc
2012-11-07 15:11:37 -08:00
Dhruba Borthakur
9b87a2bae8 Avoid doing a exhaustive search when looking for overlapping files.
Summary:
The Version::GetOverlappingInputs() is called multiple times in
the compaction code path. Eack invocation does a binary search
for overlapping files in the specified key range.
This patch remembers the offset of an overlapped file when
GetOverlappingInputs() is called the first time within
a compaction run. Suceeding calls to GetOverlappingInputs()
uses the remembered index to avoid the binary search.

I measured that 1000 iterations of GetOverlappingInputs
takes around 4500 microseconds without this patch. If I use
this patch with the hint on every invocation, then 1000
iterations take about 3900 microsecond.

Test Plan: make check OPT=-g

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: MarkCallaghan, emayanke, sheki

Differential Revision: https://reviews.facebook.net/D6513
2012-11-07 11:47:17 -08:00
Dhruba Borthakur
aa42c66814 Fix all warnings generated by -Wall option to the compiler.
Summary:
The default compilation process now uses "-Wall" to compile.
Fix all compilation error generated by gcc.

Test Plan: make all check

Reviewers: heyongqiang, emayanke, sheki

Reviewed By: heyongqiang

CC: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D6525
2012-11-06 14:07:31 -08:00
Dhruba Borthakur
5f91868cee Merge branch 'master' into performance
Conflicts:
	db/version_set.cc
	util/options.cc
2012-11-05 16:51:55 -08:00
Dhruba Borthakur
cb7a00227f The method GetOverlappingInputs should use binary search.
Summary:
The method Version::GetOverlappingInputs used a sequential search
to map a kay-range to a set of files. But the files are arranged
in ascending order of key, so a biary search is more effective.

This patch implements Version::GetOverlappingInputsBinarySearch
that finds one file that corresponds to the specified key range
and then iterates backwards and forwards to find all overlapping
files.

This patch is critical for making compactions efficient, especially
when there are thousands of files in a single level.

I measured that 1000 iterations of TEST_MaxNextLevelOverlappingBytes
takes 16000 microseconds without this patch. With this patch, the
same method takes about 4600 microseconds.

Test Plan: Almost all unit tests in db_test uses this method to lookup keys.

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: MarkCallaghan, emayanke, sheki

Differential Revision: https://reviews.facebook.net/D6465
2012-11-05 16:08:01 -08:00
heyongqiang
f1a7c735b5 fix complie error
Summary:

as subject

Test Plan:n/a
2012-11-05 10:30:19 -08:00
heyongqiang
d55c2ba305 Add a tool to change number of levels
Summary: as subject.

Test Plan: manually test it, will add a testcase

Reviewers: dhruba, MarkCallaghan

Differential Revision: https://reviews.facebook.net/D6345
2012-11-05 10:17:39 -08:00
Dhruba Borthakur
53e04311b1 Merge branch 'master' into performance
Conflicts:
	db/db_bench.cc
	util/options.cc
2012-10-29 14:18:00 -07:00
Dhruba Borthakur
5b0fe6c73b Greedy algorithm for picking files to compact.
Summary:
It is best if we pick the largest file to compact in a level.
This reduces the write amplification factor for compactions.
Each level has an auxiliary data structure called files_by_size_
that sorts all files by their size. This data structure is
updated when a new version is created.

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D6195
2012-10-25 18:27:53 -07:00
Dhruba Borthakur
8fb5f40468 firstIndex fix for multi-threaded compaction code.
Summary:
Prior to multi-threaded compaction, wrap-around would be done by using
current_->files_[level[0]. With this change we should be
using the first file for which f->being_compacted is not true.

1ca0584345 (commitcomment-2041516)

Test Plan: make check

Differential Revision: https://reviews.facebook.net/D6165
2012-10-25 08:44:47 -07:00
Dhruba Borthakur
3b06f94fa2 Merge branch 'master' into performance
Conflicts:
	db/db_impl.cc
	db/db_impl.h
	db/version_set.cc
2012-10-23 22:30:07 -07:00
heyongqiang
5010daa7a8 add "seek_compaction" to log for better debug Summary:
Summary: as subject

Test Plan: compile

Reviewers: dhruba

Reviewed By: dhruba

CC: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D6117
2012-10-22 10:00:25 -07:00
Dhruba Borthakur
1ca0584345 This is the mega-patch multi-threaded compaction
published in https://reviews.facebook.net/D5997.

Summary:
This patch allows compaction to occur in multiple background threads
concurrently.

If a manual compaction is issued, the system falls back to a
single-compaction-thread model. This is done to ensure correctess
and simplicity of code. When the manual compaction is finished,
the system resumes its concurrent-compaction mode automatically.

The updates to the manifest are done via group-commit approach.

Test Plan: run db_bench
2012-10-19 14:00:53 -07:00
Dhruba Borthakur
c1bb32e1ba Trigger read compaction only if seeks to storage are incurred.
Summary:
In the current code, a Get() call can trigger compaction if it has to look at more than one file. This causes unnecessary compaction because looking at more than one file is a penalty only if the file is not yet in the cache. Also, th current code counts these files before the bloom filter check is applied.

This patch counts a 'seek' only if the file fails the bloom filter
check and has to read in data block(s) from the storage.

This patch also counts a 'seek' if a file is not present in the file-cache, because opening a file means that its index blocks need to be read into cache.

Test Plan: unit test attached. I will probably add one more unti tests.

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D5709
2012-09-28 11:10:52 -07:00
Dhruba Borthakur
24eea931ef If ReadCompaction is switched off, then it is better to not even submit background compaction jobs.
Summary:
If ReadCompaction is switched off, then it is better to not even
submit background compaction jobs. I see about 3% increase in
read-throughput on a pure memory database.

Test Plan: run db_bench

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5673
2012-09-25 11:07:01 -07:00
Dhruba Borthakur
ae36e509f8 The BackupAPI should also list the length of the manifest file.
Summary:
The GetLiveFiles() api lists the set of sst files and the current
MANIFEST file. But the database continues to append new data to the
MANIFEST file even when the application is backing it up to the
backup location. This means that the database-version that is
stored in the MANIFEST FILE in the backup location
does not correspond to the sst files returned by GetLiveFiles.

This API adds a new parameter to GetLiveFiles. This new parmeter
returns the current size of the MANIFEST file.

Test Plan: Unit test attached.

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5631
2012-09-25 03:13:25 -07:00
Dhruba Borthakur
bb2dcd2457 Segfault in DoCompactionWork caused by buffer overflow
Summary:
The code was allocating 200 bytes on the stack but it
writes 256 bytes into the array.

x8a8ea5 std::_Rb_tree<>::erase()
    @     0x7f134bee7eb0 (unknown)
    @           0x8a8ea5 std::_Rb_tree<>::erase()
    @           0x8a35d6 leveldb::DBImpl::CleanupCompaction()
    @           0x8a7810 leveldb::DBImpl::BackgroundCompaction()
    @           0x8a804d leveldb::DBImpl::BackgroundCall()
    @           0x8c4eff leveldb::(anonymous namespace)::PosixEnv::BGThreadWrapper()
    @     0x7f134b3c010d start_thread
    @     0x7f134bf9f10d clone

Test Plan: run db_bench with overwrite option

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5595
2012-09-21 10:55:38 -07:00
heyongqiang
a8464ed820 add an option to disable seek compaction
Summary:
as subject. This diff should be good for benchmarking.

will send another diff to make it better in the case the seek compaction is enable.
In that coming diff, will not count a seek if the bloomfilter filters.

Test Plan: build

Reviewers: dhruba, MarkCallaghan

Reviewed By: MarkCallaghan

Differential Revision: https://reviews.facebook.net/D5481
2012-09-17 13:59:57 -07:00
Dhruba Borthakur
ba55d77b5d Ability to take a file-lvel snapshot from leveldb.
Summary:
A set of apis that allows an application to backup data from the
leveldb database based on a set of files.

Test Plan: unint test attached. more coming soon.

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5439
2012-09-17 09:14:50 -07:00
Dhruba Borthakur
fe93631678 Clean up compiler warnings generated by -Wall option.
Summary:
Clean up compiler warnings generated by -Wall option.
make clean all OPT=-Wall

This is a pre-requisite before making a new release.

Test Plan: compile and run unit tests

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D5019
2012-08-29 14:24:51 -07:00
heyongqiang
a4f9b8b49e merge 1.5
Summary:

as subject

Test Plan:

db_test table_test

Reviewers: dhruba
2012-08-28 11:43:33 -07:00
heyongqiang
d3759ca121 fix db_test error with scribe logger turned on
Summary: as subject

Test Plan: db_test

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D4929
2012-08-28 11:22:58 -07:00
Dhruba Borthakur
fc20273e73 Introduce a new method Env->Fsync() that issues fsync (instead of fdatasync).
Summary:
Introduce a new method Env->Fsync() that issues fsync (instead of fdatasync).
This is needed for data durability when running on ext3 filesystems.
Added options to the benchmark db_bench to generate performance numbers
with either fsync or fdatasync enabled.

Cleaned up Makefile to build leveldb_shell only when building the thrift
leveldb server.

Test Plan: build and run benchmark

Reviewers: heyongqiang

Reviewed By: heyongqiang

Differential Revision: https://reviews.facebook.net/D4911
2012-08-27 21:24:17 -07:00
heyongqiang
1de83cc2ac add more logs
Summary:
as subject

add a tool to read sst file

as subject.

./sst_reader --command=check --file=
./sst_reader --command=scan --file=

Test Plan:
db_test

run this command

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D4881
2012-08-24 15:20:49 -07:00
heyongqiang
1c99b0a6b3 add more logs
Summary:

as subject

Test Plan:db_test

Reviewers: dhruba
2012-08-24 15:18:43 -07:00
Dhruba Borthakur
f3ee54526f Utility to dump manifest contents.
Summary:
./manifest_dump --file=/tmp/dbbench/MANIFEST-000002

Output looks like

manifest_file_number 30 next_file_number 31 last_sequence 388082 log_number 28  prev_log_number 0
--- level 0 ---
--- level 1 ---
--- level 2 ---
 5:3244155['0000000000000000' @ 1 : 1 .. '0000000000028220' @ 28221 : 1]
 7:3244177['0000000000028221' @ 28222 : 1 .. '0000000000056441' @ 56442 : 1]
 9:3244156['0000000000056442' @ 56443 : 1 .. '0000000000084662' @ 84663 : 1]
 11:3244178['0000000000084663' @ 84664 : 1 .. '0000000000112883' @ 112884 : 1]
 13:3244158['0000000000112884' @ 112885 : 1 .. '0000000000141104' @ 141105 : 1]
 15:3244176['0000000000141105' @ 141106 : 1 .. '0000000000169325' @ 169326 : 1]
 17:3244156['0000000000169326' @ 169327 : 1 .. '0000000000197546' @ 197547 : 1]
 19:3244178['0000000000197547' @ 197548 : 1 .. '0000000000225767' @ 225768 : 1]
 21:3244155['0000000000225768' @ 225769 : 1 .. '0000000000253988' @ 253989 : 1]
 23:3244179['0000000000253989' @ 253990 : 1 .. '0000000000282209' @ 282210 : 1]
 25:3244157['0000000000282210' @ 282211 : 1 .. '0000000000310430' @ 310431 : 1]
 27:3244176['0000000000310431' @ 310432 : 1 .. '0000000000338651' @ 338652 : 1]
 29:3244156['0000000000338652' @ 338653 : 1 .. '0000000000366872' @ 366873 : 1]
--- level 3 ---
--- level 4 ---
--- level 5 ---
--- level 6 ---

Test Plan: run on test directory created by dbbench

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: hustliubo

Differential Revision: https://reviews.facebook.net/D4743
2012-08-24 15:17:09 -07:00
heyongqiang
af6fa308b0 regression for trigger compaction logic
Summary: as subject

Test Plan: manually run db_bench confirmed

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D4809
2012-08-22 11:41:33 -07:00
heyongqiang
6ba1f17789 adding a scribe logger in leveldb to log leveldb deploy stats
Summary:
as subject.

A new log is written to scribe via thrift client when a new db is opened and when there is
a compaction.

a new option var scribe_log_db_stats is added.

Test Plan: manually checked using command "ptail -time 0 leveldb_deploy_stats"

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D4659
2012-08-21 11:43:22 -07:00
Dhruba Borthakur
2aa514ec8c Utility to dump manifest contents.
Summary:
./manifest_dump --file=/tmp/dbbench/MANIFEST-000002

Output looks like

manifest_file_number 30 next_file_number 31 last_sequence 388082 log_number 28  prev_log_number 0
--- level 0 ---
--- level 1 ---
--- level 2 ---
 5:3244155['0000000000000000' @ 1 : 1 .. '0000000000028220' @ 28221 : 1]
 7:3244177['0000000000028221' @ 28222 : 1 .. '0000000000056441' @ 56442 : 1]
 9:3244156['0000000000056442' @ 56443 : 1 .. '0000000000084662' @ 84663 : 1]
 11:3244178['0000000000084663' @ 84664 : 1 .. '0000000000112883' @ 112884 : 1]
 13:3244158['0000000000112884' @ 112885 : 1 .. '0000000000141104' @ 141105 : 1]
 15:3244176['0000000000141105' @ 141106 : 1 .. '0000000000169325' @ 169326 : 1]
 17:3244156['0000000000169326' @ 169327 : 1 .. '0000000000197546' @ 197547 : 1]
 19:3244178['0000000000197547' @ 197548 : 1 .. '0000000000225767' @ 225768 : 1]
 21:3244155['0000000000225768' @ 225769 : 1 .. '0000000000253988' @ 253989 : 1]
 23:3244179['0000000000253989' @ 253990 : 1 .. '0000000000282209' @ 282210 : 1]
 25:3244157['0000000000282210' @ 282211 : 1 .. '0000000000310430' @ 310431 : 1]
 27:3244176['0000000000310431' @ 310432 : 1 .. '0000000000338651' @ 338652 : 1]
 29:3244156['0000000000338652' @ 338653 : 1 .. '0000000000366872' @ 366873 : 1]
--- level 3 ---
--- level 4 ---
--- level 5 ---
--- level 6 ---

Test Plan: run on test directory created by dbbench

Reviewers: heyongqiang

Reviewed By: heyongqiang

CC: hustliubo

Differential Revision: https://reviews.facebook.net/D4743
2012-08-17 22:36:59 -07:00
heyongqiang
680e571c4c add compaction log Summary:
Summary:
add compaction summary to log

log looks like:

2012/08/17-18:18:32.557334 7fdcaa2bb700 Compaction summary: Base level 0, input file:[11 9 7 ],[]

Test Plan: tested via db_test

Reviewers: dhruba

Differential Revision: https://reviews.facebook.net/D4749
2012-08-17 19:29:39 -07:00
heyongqiang
4e4b6812ff Make some variables configurable for each db instance
Summary:
Make configurable 'targetFileSize', 'targetFileSizeMultiplier',
'maxBytesForLevelBase', 'maxBytesForLevelMultiplier',
'expandedCompactionFactor', 'maxGrandParentOverlapFactor'

Test Plan: N/A

Reviewers: dhruba

Reviewed By: dhruba

Differential Revision: https://reviews.facebook.net/D3801
2012-06-27 14:36:31 -07:00
Sanjay Ghemawat
85584d497e Added bloom filter support.
In particular, we add a new FilterPolicy class.  An instance
of this class can be supplied in Options when opening a
database.  If supplied, the instance is used to generate
summaries of keys (e.g., a bloom filter) which are placed in
sstables.  These summaries are consulted by DB::Get() so we
can avoid reading sstable blocks that are guaranteed to not
contain the key we are looking for.

This change provides one implementation of FilterPolicy
based on bloom filters.

Other changes:
- Updated version number to 1.4.
- Some build tweaks.
- C binding for CompactRange.
- A few more benchmarks: deleteseq, deleterandom, readmissing, seekrandom.
- Minor .gitignore update.
2012-04-17 08:36:46 -07:00
Sanjay Ghemawat
239ac9d2de avoid very large compactions; fix build on Linux 2012-02-02 09:34:14 -08:00
Hans Wennborg
36a5f8ed7f A number of fixes:
- Replace raw slice comparison with a call to user comparator.
  Added test for custom comparators.

- Fix end of namespace comments.

- Fixed bug in picking inputs for a level-0 compaction.

  When finding overlapping files, the covered range may expand
  as files are added to the input set.  We now correctly expand
  the range when this happens instead of continuing to use the
  old range.  For example, suppose L0 contains files with the
  following ranges:

      F1: a .. d
      F2:    c .. g
      F3:       f .. j

  and the initial compaction target is F3.  We used to search
  for range f..j which yielded {F2,F3}.  However we now expand
  the range as soon as another file is added.  In this case,
  when F2 is added, we expand the range to c..j and restart the
  search.  That picks up file F1 as well.

  This change fixes a bug related to deleted keys showing up
  incorrectly after a compaction as described in Issue 44.

(Sync with upstream @25072954)
2011-10-31 17:22:06 +00:00
Gabor Cselle
299ccedfec A number of bugfixes:
- Added DB::CompactRange() method.

  Changed manual compaction code so it breaks up compactions of
  big ranges into smaller compactions.

  Changed the code that pushes the output of memtable compactions
  to higher levels to obey the grandparent constraint: i.e., we
  must never have a single file in level L that overlaps too
  much data in level L+1 (to avoid very expensive L-1 compactions).

  Added code to pretty-print internal keys.

- Fixed bug where we would not detect overlap with files in
  level-0 because we were incorrectly using binary search
  on an array of files with overlapping ranges.

  Added "leveldb.sstables" property that can be used to dump
  all of the sstables and ranges that make up the db state.

- Removing post_write_snapshot support.  Email to leveldb mailing
  list brought up no users, just confusion from one person about
  what it meant.

- Fixing static_cast char to unsigned on BIG_ENDIAN platforms.

  Fixes	Issue 35 and Issue 36.

- Comment clarification to address leveldb Issue 37.

- Change license in posix_logger.h to match other files.

- A build problem where uint32 was used instead of uint32_t.

Sync with upstream @24408625
2011-10-05 16:30:28 -07:00
gabor@google.com
7263023651 Bugfixes: for Get(), don't hold mutex while writing log.
- Fix bug in Get: when it triggers a compaction, it could sometimes
  mark the compaction with the wrong level (if there was a gap
  in the set of levels examined for the Get).

- Do not hold mutex while writing to the log file or to the
  MANIFEST file.

  Added a new benchmark that runs a writer thread concurrently with
  reader threads.

  Percentiles
  ------------------------------
  micros/op: avg  median 99   99.9  99.99  99.999 max
  ------------------------------------------------------
  before:    42   38     110  225   32000  42000  48000
  after:     24   20     55   65    130    1100   7000

- Fixed race in optimized Get.  It should have been using the
  pinned memtables, not the current memtables.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@50 62dab493-f737-651d-591e-8d6aee1b9529
2011-09-01 19:08:02 +00:00
dgrogan@chromium.org
a05525d13b @23023120
git-svn-id: https://leveldb.googlecode.com/svn/trunk@47 62dab493-f737-651d-591e-8d6aee1b9529
2011-08-06 00:19:37 +00:00
gabor@google.com
60bd8015f2 Speed up Snappy uncompression, new Logger interface.
- Removed one copy of an uncompressed block contents changing
  the signature of Snappy_Uncompress() so it uncompresses into a
  flat array instead of a std::string.
        
  Speeds up readrandom ~10%.

- Instead of a combination of Env/WritableFile, we now have a
  Logger interface that can be easily overridden applications
  that want to supply their own logging.

- Separated out the gcc and Sun Studio parts of atomic_pointer.h
  so we can use 'asm', 'volatile' keywords for Sun Studio.




git-svn-id: https://leveldb.googlecode.com/svn/trunk@39 62dab493-f737-651d-591e-8d6aee1b9529
2011-07-21 02:40:18 +00:00
gabor@google.com
6872ace901 Sun Studio support, and fix for test related memory fixes.
- LevelDB patch for Sun Studio
  Based on a patch submitted by Theo Schlossnagle - thanks!
  This fixes Issue 17.

- Fix a couple of test related memory leaks.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@38 62dab493-f737-651d-591e-8d6aee1b9529
2011-07-19 23:36:47 +00:00
gabor@google.com
6699c7ebe6 Small tweaks and bugfixes for Issue 18 and 19.
Slight tweak to the no-overlap optimization: only push to
level 2 to reduce the amount of wasted space when the same
small key range is being repeatedly overwritten.

Fix for Issue 18: Avoid failure on Windows by avoiding
deletion of lock file until the end of DestroyDB().

Fix for Issue 19: Disregard sequence numbers when checking for 
overlap in sstable ranges. This fixes issue 19: when writing 
the same key over and over again, we would generate a sequence 
of sstables that were never merged together since their sequence
numbers were disjoint.

Don't ignore map/unmap error checks.

Miscellaneous fixes for small problems Sanjay found while diagnosing
issue/9 and issue/16 (corruption_testr failures).
- log::Reader reports the record type when it finds an unexpected type.
- log::Reader no longer reports an error when it encounters an expected
  zero record regardless of the setting of the "checksum" flag.
- Added a missing forward declaration.
- Documented a side-effects of larger write buffer sizes
  (longer recovery time).



git-svn-id: https://leveldb.googlecode.com/svn/trunk@37 62dab493-f737-651d-591e-8d6aee1b9529
2011-07-15 00:20:57 +00:00
gabor@google.com
ccf0fcd5c2 A number of smaller fixes and performance improvements:
- Implemented Get() directly instead of building on top of a full
  merging iterator stack.  This speeds up the "readrandom" benchmark
  by up to 15-30%.

- Fixed an opensource compilation problem.
  Added --db=<name> flag to control where the database is placed.

- Automatically compact a file when we have done enough
  overlapping seeks to that file.

- Fixed a performance bug where we would read from at least one
  file in a level even if none of the files overlapped the key
  being read.

- Makefile fix for Mac OSX installations that have XCode 4 without XCode 3.

- Unified the two occurrences of binary search in a file-list
  into one routine.

- Found and fixed a bug where we would unnecessarily search the
  last file when looking for a key larger than all data in the
  level.

- A fix to avoid the need for trivial move compactions and
  therefore gets rid of two out of five syncs in "fillseq".

- Removed the MANIFEST file write when switching to a new
  memtable/log-file for a 10-20% improvement on fill speed on ext4.

- Adding a SNAPPY setting in the Makefile for folks who have
  Snappy installed. Snappy compresses values and speeds up writes.



git-svn-id: https://leveldb.googlecode.com/svn/trunk@32 62dab493-f737-651d-591e-8d6aee1b9529
2011-06-22 02:36:45 +00:00
dgrogan@chromium.org
da79909507 sync with upstream @ 21409451
Check the NEWS file for details of what changed.

git-svn-id: https://leveldb.googlecode.com/svn/trunk@28 62dab493-f737-651d-591e-8d6aee1b9529
2011-05-21 02:17:43 +00:00
dgrogan@chromium.org
ba6dac0e80 @20776309
* env_chromium.cc should not export symbols.
* Fix MSVC warnings.
* Removed large value support.
* Fix broken reference to documentation file

git-svn-id: https://leveldb.googlecode.com/svn/trunk@24 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-20 22:48:11 +00:00
dgrogan@chromium.org
69c6d38342 reverting disastrous MOE commit, returning to r21
git-svn-id: https://leveldb.googlecode.com/svn/trunk@23 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-19 23:11:15 +00:00
dgrogan@chromium.org
b743906eea Revision created by MOE tool push_codebase.
MOE_MIGRATION=


git-svn-id: https://leveldb.googlecode.com/svn/trunk@22 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-19 23:01:25 +00:00
dgrogan@chromium.org
b409afe968 chmod a-x
git-svn-id: https://leveldb.googlecode.com/svn/trunk@21 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-18 23:15:58 +00:00
dgrogan@chromium.org
f779e7a5d8 @20602303. Default file permission is now 755.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@20 62dab493-f737-651d-591e-8d6aee1b9529
2011-04-12 19:38:58 +00:00
jorlow@chromium.org
4671a695fc Move include files into a leveldb subdir.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@18 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-30 18:35:40 +00:00
jorlow@chromium.org
e2da744e12 Upstream changes.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@16 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-28 20:43:44 +00:00
jorlow@chromium.org
8303bb1b33 Pull from upstream.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@14 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-22 23:24:02 +00:00
jorlow@chromium.org
13b72af77b More changes from upstream.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@12 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-22 18:32:49 +00:00
jorlow@chromium.org
f67e15e50f Initial checkin.
git-svn-id: https://leveldb.googlecode.com/svn/trunk@2 62dab493-f737-651d-591e-8d6aee1b9529
2011-03-18 22:37:00 +00:00