Commit Graph

14 Commits

Author SHA1 Message Date
leveldb Team
1d6e8d64ee Add support for Zstd-based compression in LevelDB.
This change implements support for Zstd-based compression in LevelDB. Building
up from the Snappy compression (which has been supported since inception), this
change adds Zstd as an alternate compression algorithm.

We are implementing this to provide alternative options for users who might
have different performance and efficiency requirements. For instance, the
Zstandard website (https://facebook.github.io/zstd/) claims that the Zstd
algorithm can achieve around 30% higher compression ratios than Snappy, with
relatively smaller (~10%) slowdowns in de/compression speeds.

Benchmarking results:

$ blaze-bin/third_party/leveldb/db_bench
LevelDB:    version 1.23
Date:       Thu Feb  2 18:50:06 2023
CPU:        56 * Intel(R) Xeon(R) CPU E5-2690 v4 @ 2.60GHz
CPUCache:   35840 KB
Keys:       16 bytes each
Values:     100 bytes each (50 bytes after compression)
Entries:    1000000
RawSize:    110.6 MB (estimated)
FileSize:   62.9 MB (estimated)
------------------------------------------------
fillseq      :       2.613 micros/op;   42.3 MB/s
fillsync     :    3924.432 micros/op;    0.0 MB/s (1000 ops)
fillrandom   :       3.609 micros/op;   30.7 MB/s
overwrite    :       4.508 micros/op;   24.5 MB/s
readrandom   :       6.136 micros/op; (864322 of 1000000 found)
readrandom   :       5.446 micros/op; (864083 of 1000000 found)
readseq      :       0.180 micros/op;  613.3 MB/s
readreverse  :       0.321 micros/op;  344.7 MB/s
compact      :  827043.000 micros/op;
readrandom   :       4.603 micros/op; (864105 of 1000000 found)
readseq      :       0.169 micros/op;  656.3 MB/s
readreverse  :       0.315 micros/op;  350.8 MB/s
fill100K     :     854.009 micros/op;  111.7 MB/s (1000 ops)
crc32c       :       1.227 micros/op; 3184.0 MB/s (4K per op)
snappycomp   :       3.610 micros/op; 1081.9 MB/s (output: 55.2%)
snappyuncomp :       0.691 micros/op; 5656.3 MB/s
zstdcomp     :      15.731 micros/op;  248.3 MB/s (output: 44.1%)
zstduncomp   :       4.218 micros/op;  926.2 MB/s
PiperOrigin-RevId: 509957778
2023-03-28 16:49:13 -07:00
Victor Costan
3f934e3705 Switch from C headers to C++ headers.
This CL makes the following substitutions.

* assert.h -> cassert
* math.h -> cmath
* stdarg.h -> cstdarg
* stddef.h -> cstddef
* stdint.h -> cstdint
* stdio.h -> cstdio
* stdlib.h -> cstdlib
* string.h -> cstring

PiperOrigin-RevId: 309080151
2020-04-29 20:51:13 +00:00
Chris Mumford
9bd23c7676 Correct class/structure declaration order.
1. Correct the class/struct declaration order to be IAW
   the Google C++ style guide[1].
2. For non-copyable classes, switched from non-implemented
   private methods to explicitly deleted[2] methods.
3. Minor const and member initialization fixes.

[1] https://google.github.io/styleguide/cppguide.html#Declaration_Order
[2] http://eel.is/c++draft/dcl.fct.def.delete

PiperOrigin-RevId: 246521844
2019-05-03 09:48:57 -07:00
Chris Mumford
297e66afc1 Format all files IAW the Google C++ Style Guide.
Use clang-format to correct formatting to be in agreement with the [Google C++ Style Guide](https://google.github.io/styleguide/cppguide.html). Doing this simplifies the process of accepting changes. Also fixed a few warnings flagged by clang-tidy.

PiperOrigin-RevId: 246350737
2019-05-02 19:04:50 -07:00
costan
09217fd067 Replace NULL with nullptr in C++ files.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=192365747
2018-04-10 16:26:43 -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
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
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
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
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