Skip to content

Commit

Permalink
Release Snappy 1.1.1.
Browse files Browse the repository at this point in the history 
R=jeff


git-svn-id: https://snappy.googlecode.com/svn/trunk@81 03e5f5b5-db94-4691-08a0-1a8bf15f6143
  • Loading branch information
snappy.mirrorbot@gmail.com committed Oct 15, 2013
1 parent 6bc39e2 commit eeead8d
Show file tree
Hide file tree
Showing 3 changed files with 283 additions and 2 deletions.
268 changes: 268 additions & 0 deletions ChangeLog
View file
@@ -1,3 +1,271 @@
------------------------------------------------------------------------
r80 | snappy.mirrorbot@gmail.com | 2013-08-13 14:55:00 +0200 (Tue, 13 Aug 2013) | 6 lines

Add autoconf tests for size_t and ssize_t. Sort-of resolves public issue 79;
it would solve the problem if MSVC typically used autoconf. However, it gives
a natural place (config.h) to put the typedef even for MSVC.

R=jsbell

------------------------------------------------------------------------
r79 | snappy.mirrorbot@gmail.com | 2013-07-29 13:06:44 +0200 (Mon, 29 Jul 2013) | 14 lines

When we compare the number of bytes produced with the offset for a
backreference, make the signedness of the bytes produced clear,
by sticking it into a size_t. This avoids a signed/unsigned compare
warning from MSVC (public issue 71), and also is slightly clearer.

Since the line is now so long the explanatory comment about the -1u
trick has to go somewhere else anyway, I used the opportunity to
explain it in slightly more detail.

This is a purely stylistic change; the emitted assembler from GCC
is identical.

R=jeff

------------------------------------------------------------------------
r78 | snappy.mirrorbot@gmail.com | 2013-06-30 21:24:03 +0200 (Sun, 30 Jun 2013) | 111 lines

In the fast path for decompressing literals, instead of checking
whether there's 16 bytes free and then checking right afterwards
(when having subtracted the literal size) that there are now
5 bytes free, just check once for 21 bytes. This skips a compare
and a branch; although it is easily predictable, it is still
a few cycles on a fast path that we would like to get rid of.

Benchmarking this yields very confusing results. On open-source
GCC 4.8.1 on Haswell, we get exactly the expected results; the
benchmarks where we hit the fast path for literals (in particular
the two HTML benchmarks and the protobuf benchmark) give very nice
speedups, and the others are not really affected.

However, benchmarks with Google's GCC branch on other hardware
is much less clear. It seems that we have a weak loss in some cases
(and the win for the “typical” win cases are not nearly as clear),
but that it depends on microarchitecture and plain luck in how we run
the benchmark. Looking at the generated assembler, it seems that
the removal of the if causes other large-scale changes in how the
function is laid out, which makes it likely that this is just bad luck.

Thus, we should keep this change, even though its exact current impact is
unclear; it's a sensible change per se, and dropping it on the basis of
microoptimization for a given compiler (or even branch of a compiler)
would seem like a bad strategy in the long run.

Microbenchmark results (all in 64-bit, opt mode):

Nehalem, Google GCC:

Benchmark Base (ns) New (ns) Improvement
------------------------------------------------------------------------------
BM_UFlat/0 76747 75591 1.3GB/s html +1.5%
BM_UFlat/1 765756 757040 886.3MB/s urls +1.2%
BM_UFlat/2 10867 10893 10.9GB/s jpg -0.2%
BM_UFlat/3 124 131 1.4GB/s jpg_200 -5.3%
BM_UFlat/4 31663 31596 2.8GB/s pdf +0.2%
BM_UFlat/5 314162 308176 1.2GB/s html4 +1.9%
BM_UFlat/6 29668 29746 790.6MB/s cp -0.3%
BM_UFlat/7 12958 13386 796.4MB/s c -3.2%
BM_UFlat/8 3596 3682 966.0MB/s lsp -2.3%
BM_UFlat/9 1019193 1033493 953.3MB/s xls -1.4%
BM_UFlat/10 239 247 775.3MB/s xls_200 -3.2%
BM_UFlat/11 236411 240271 606.9MB/s txt1 -1.6%
BM_UFlat/12 206639 209768 571.2MB/s txt2 -1.5%
BM_UFlat/13 627803 635722 641.4MB/s txt3 -1.2%
BM_UFlat/14 845932 857816 538.2MB/s txt4 -1.4%
BM_UFlat/15 402107 391670 1.2GB/s bin +2.7%
BM_UFlat/16 283 279 683.6MB/s bin_200 +1.4%
BM_UFlat/17 46070 46815 781.5MB/s sum -1.6%
BM_UFlat/18 5053 5163 782.0MB/s man -2.1%
BM_UFlat/19 79721 76581 1.4GB/s pb +4.1%
BM_UFlat/20 251158 252330 697.5MB/s gaviota -0.5%
Sum of all benchmarks 4966150 4980396 -0.3%


Sandy Bridge, Google GCC:

Benchmark Base (ns) New (ns) Improvement
------------------------------------------------------------------------------
BM_UFlat/0 42850 42182 2.3GB/s html +1.6%
BM_UFlat/1 525660 515816 1.3GB/s urls +1.9%
BM_UFlat/2 7173 7283 16.3GB/s jpg -1.5%
BM_UFlat/3 92 91 2.1GB/s jpg_200 +1.1%
BM_UFlat/4 15147 14872 5.9GB/s pdf +1.8%
BM_UFlat/5 199936 192116 2.0GB/s html4 +4.1%
BM_UFlat/6 12796 12443 1.8GB/s cp +2.8%
BM_UFlat/7 6588 6400 1.6GB/s c +2.9%
BM_UFlat/8 2010 1951 1.8GB/s lsp +3.0%
BM_UFlat/9 761124 763049 1.3GB/s xls -0.3%
BM_UFlat/10 186 189 1016.1MB/s xls_200 -1.6%
BM_UFlat/11 159354 158460 918.6MB/s txt1 +0.6%
BM_UFlat/12 139732 139950 856.1MB/s txt2 -0.2%
BM_UFlat/13 429917 425027 961.7MB/s txt3 +1.2%
BM_UFlat/14 585255 587324 785.8MB/s txt4 -0.4%
BM_UFlat/15 276186 266173 1.8GB/s bin +3.8%
BM_UFlat/16 205 207 925.5MB/s bin_200 -1.0%
BM_UFlat/17 24925 24935 1.4GB/s sum -0.0%
BM_UFlat/18 2632 2576 1.5GB/s man +2.2%
BM_UFlat/19 40546 39108 2.8GB/s pb +3.7%
BM_UFlat/20 175803 168209 1048.9MB/s gaviota +4.5%
Sum of all benchmarks 3408117 3368361 +1.2%


Haswell, upstream GCC 4.8.1:

Benchmark Base (ns) New (ns) Improvement
------------------------------------------------------------------------------
BM_UFlat/0 46308 40641 2.3GB/s html +13.9%
BM_UFlat/1 513385 514706 1.3GB/s urls -0.3%
BM_UFlat/2 6197 6151 19.2GB/s jpg +0.7%
BM_UFlat/3 61 61 3.0GB/s jpg_200 +0.0%
BM_UFlat/4 13551 13429 6.5GB/s pdf +0.9%
BM_UFlat/5 198317 190243 2.0GB/s html4 +4.2%
BM_UFlat/6 14768 12560 1.8GB/s cp +17.6%
BM_UFlat/7 6453 6447 1.6GB/s c +0.1%
BM_UFlat/8 1991 1980 1.8GB/s lsp +0.6%
BM_UFlat/9 766947 770424 1.2GB/s xls -0.5%
BM_UFlat/10 170 169 1.1GB/s xls_200 +0.6%
BM_UFlat/11 164350 163554 888.7MB/s txt1 +0.5%
BM_UFlat/12 145444 143830 832.1MB/s txt2 +1.1%
BM_UFlat/13 437849 438413 929.2MB/s txt3 -0.1%
BM_UFlat/14 603587 605309 759.8MB/s txt4 -0.3%
BM_UFlat/15 249799 248067 1.9GB/s bin +0.7%
BM_UFlat/16 191 188 1011.4MB/s bin_200 +1.6%
BM_UFlat/17 26064 24778 1.4GB/s sum +5.2%
BM_UFlat/18 2620 2601 1.5GB/s man +0.7%
BM_UFlat/19 44551 37373 3.0GB/s pb +19.2%
BM_UFlat/20 165408 164584 1.0GB/s gaviota +0.5%
Sum of all benchmarks 3408011 3385508 +0.7%

------------------------------------------------------------------------
r77 | snappy.mirrorbot@gmail.com | 2013-06-14 23:42:26 +0200 (Fri, 14 Jun 2013) | 92 lines

Make the two IncrementalCopy* functions take in an ssize_t instead of a len,
in order to avoid having to do 32-to-64-bit signed conversions on a hot path
during decompression. (Also fixes some MSVC warnings, mentioned in public
issue 75, but more of those remain.) They cannot be size_t because we expect
them to go negative and test for that.

This saves a few movzwl instructions, yielding ~2% speedup in decompression.


Sandy Bridge:

Benchmark Base (ns) New (ns) Improvement
-------------------------------------------------------------------------------------------------
BM_UFlat/0 48009 41283 2.3GB/s html +16.3%
BM_UFlat/1 531274 513419 1.3GB/s urls +3.5%
BM_UFlat/2 7378 7062 16.8GB/s jpg +4.5%
BM_UFlat/3 92 92 2.0GB/s jpg_200 +0.0%
BM_UFlat/4 15057 14974 5.9GB/s pdf +0.6%
BM_UFlat/5 204323 193140 2.0GB/s html4 +5.8%
BM_UFlat/6 13282 12611 1.8GB/s cp +5.3%
BM_UFlat/7 6511 6504 1.6GB/s c +0.1%
BM_UFlat/8 2014 2030 1.7GB/s lsp -0.8%
BM_UFlat/9 775909 768336 1.3GB/s xls +1.0%
BM_UFlat/10 182 184 1043.2MB/s xls_200 -1.1%
BM_UFlat/11 167352 161630 901.2MB/s txt1 +3.5%
BM_UFlat/12 147393 142246 842.8MB/s txt2 +3.6%
BM_UFlat/13 449960 432853 944.4MB/s txt3 +4.0%
BM_UFlat/14 620497 594845 775.9MB/s txt4 +4.3%
BM_UFlat/15 265610 267356 1.8GB/s bin -0.7%
BM_UFlat/16 206 205 932.7MB/s bin_200 +0.5%
BM_UFlat/17 25561 24730 1.4GB/s sum +3.4%
BM_UFlat/18 2620 2644 1.5GB/s man -0.9%
BM_UFlat/19 45766 38589 2.9GB/s pb +18.6%
BM_UFlat/20 171107 169832 1039.5MB/s gaviota +0.8%
Sum of all benchmarks 3500103 3394565 +3.1%


Westmere:

Benchmark Base (ns) New (ns) Improvement
-------------------------------------------------------------------------------------------------
BM_UFlat/0 72624 71526 1.3GB/s html +1.5%
BM_UFlat/1 735821 722917 930.8MB/s urls +1.8%
BM_UFlat/2 10450 10172 11.7GB/s jpg +2.7%
BM_UFlat/3 117 117 1.6GB/s jpg_200 +0.0%
BM_UFlat/4 29817 29648 3.0GB/s pdf +0.6%
BM_UFlat/5 297126 293073 1.3GB/s html4 +1.4%
BM_UFlat/6 28252 27994 842.0MB/s cp +0.9%
BM_UFlat/7 12672 12391 862.1MB/s c +2.3%
BM_UFlat/8 3507 3425 1040.9MB/s lsp +2.4%
BM_UFlat/9 1004268 969395 1018.0MB/s xls +3.6%
BM_UFlat/10 233 227 844.8MB/s xls_200 +2.6%
BM_UFlat/11 230054 224981 647.8MB/s txt1 +2.3%
BM_UFlat/12 201229 196447 610.5MB/s txt2 +2.4%
BM_UFlat/13 609547 596761 685.3MB/s txt3 +2.1%
BM_UFlat/14 824362 804821 573.8MB/s txt4 +2.4%
BM_UFlat/15 371095 374899 1.3GB/s bin -1.0%
BM_UFlat/16 267 267 717.8MB/s bin_200 +0.0%
BM_UFlat/17 44623 43828 835.9MB/s sum +1.8%
BM_UFlat/18 5077 4815 841.0MB/s man +5.4%
BM_UFlat/19 74964 73210 1.5GB/s pb +2.4%
BM_UFlat/20 237987 236745 746.0MB/s gaviota +0.5%
Sum of all benchmarks 4794092 4697659 +2.1%


Istanbul:

Benchmark Base (ns) New (ns) Improvement
-------------------------------------------------------------------------------------------------
BM_UFlat/0 98614 96376 1020.4MB/s html +2.3%
BM_UFlat/1 963740 953241 707.2MB/s urls +1.1%
BM_UFlat/2 25042 24769 4.8GB/s jpg +1.1%
BM_UFlat/3 180 180 1065.6MB/s jpg_200 +0.0%
BM_UFlat/4 45942 45403 1.9GB/s pdf +1.2%
BM_UFlat/5 400135 390226 1008.2MB/s html4 +2.5%
BM_UFlat/6 37768 37392 631.9MB/s cp +1.0%
BM_UFlat/7 18585 18200 588.2MB/s c +2.1%
BM_UFlat/8 5751 5690 627.7MB/s lsp +1.1%
BM_UFlat/9 1543154 1542209 641.4MB/s xls +0.1%
BM_UFlat/10 381 388 494.6MB/s xls_200 -1.8%
BM_UFlat/11 339715 331973 440.1MB/s txt1 +2.3%
BM_UFlat/12 294807 289418 415.4MB/s txt2 +1.9%
BM_UFlat/13 906160 884094 463.3MB/s txt3 +2.5%
BM_UFlat/14 1224221 1198435 386.1MB/s txt4 +2.2%
BM_UFlat/15 516277 502923 979.5MB/s bin +2.7%
BM_UFlat/16 405 402 477.2MB/s bin_200 +0.7%
BM_UFlat/17 61640 60621 605.6MB/s sum +1.7%
BM_UFlat/18 7326 7383 549.5MB/s man -0.8%
BM_UFlat/19 94720 92653 1.2GB/s pb +2.2%
BM_UFlat/20 360435 346687 510.6MB/s gaviota +4.0%
Sum of all benchmarks 6944998 6828663 +1.7%

------------------------------------------------------------------------
r76 | snappy.mirrorbot@gmail.com | 2013-06-13 18:19:52 +0200 (Thu, 13 Jun 2013) | 9 lines

Add support for uncompressing to iovecs (scatter I/O).
Windows does not have struct iovec defined anywhere,
so we define our own version that's equal to what UNIX
typically has.

The bulk of this patch was contributed by Mohit Aron.

R=jeff

------------------------------------------------------------------------
r75 | snappy.mirrorbot@gmail.com | 2013-06-12 21:51:15 +0200 (Wed, 12 Jun 2013) | 4 lines

Some code reorganization needed for an internal change.

R=fikes

------------------------------------------------------------------------
r74 | snappy.mirrorbot@gmail.com | 2013-04-09 17:33:30 +0200 (Tue, 09 Apr 2013) | 4 lines

Supports truncated test data in zippy benchmark.

R=sesse

------------------------------------------------------------------------
r73 | snappy.mirrorbot@gmail.com | 2013-02-05 15:36:15 +0100 (Tue, 05 Feb 2013) | 4 lines

Release Snappy 1.1.0.

R=sanjay

------------------------------------------------------------------------
r72 | snappy.mirrorbot@gmail.com | 2013-02-05 15:30:05 +0100 (Tue, 05 Feb 2013) | 9 lines

Expand Down
13 changes: 13 additions & 0 deletions NEWS
View file
@@ -1,3 +1,16 @@
Snappy v1.1.1, October 15th 2013:

* Add support for uncompressing to iovecs (scatter I/O).
The bulk of this patch was contributed by Mohit Aron.

* Speed up decompression by ~2%; much more so (~13-20%) on
a few benchmarks on given compilers and CPUs.

* Fix a few issues with MSVC compilation.

* Support truncated test data in the benchmark.


Snappy v1.1.0, January 18th 2013:

* Snappy now uses 64 kB block size instead of 32 kB. On average,
Expand Down
4 changes: 2 additions & 2 deletions configure.ac
View file
@@ -1,11 +1,11 @@
m4_define([snappy_major], [1])
m4_define([snappy_minor], [1])
m4_define([snappy_patchlevel], [0])
m4_define([snappy_patchlevel], [1])

# Libtool shared library interface versions (current:revision:age)
# Update this value for every release! (A:B:C will map to foo.so.(A-C).C.B)
# http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
m4_define([snappy_ltversion], [2:4:1])
m4_define([snappy_ltversion], [3:0:2])

AC_INIT([snappy], [snappy_major.snappy_minor.snappy_patchlevel])
AC_CONFIG_MACRO_DIR([m4])
Expand Down

0 comments on commit eeead8d

Please sign in to comment.