snappy/snappy-sinksource.cc
Steinar H. Gunderson b2312c4c25 Add support for Uncompress(source, sink). Various changes to allow
Uncompress(source, sink) to get the same performance as the different
variants of Uncompress to Cord/DataBuffer/String/FlatBuffer.

Changes to efficiently support Uncompress(source, sink)
--------

a) For strings - we add support to StringByteSink to do GetAppendBuffer so we
   can write to it without copying.
b) For flat array buffers, we do GetAppendBuffer and see if we can get a full buffer.

With the above changes we get performance with ByteSource/ByteSink
that is	very close to directly using flat arrays and strings.

We add various benchmark cases to demonstrate that.

Orthogonal change
------------------

Add support for TryFastAppend() for SnappyScatteredWriter.

Benchmark results are below

CPU: Intel Core2 dL1:32KB dL2:4096KB
Benchmark              Time(ns)    CPU(ns) Iterations
-----------------------------------------------------
BM_UFlat/0               109065     108996       6410 896.0MB/s  html
BM_UFlat/1              1012175    1012343        691 661.4MB/s  urls
BM_UFlat/2                26775      26771      26149 4.4GB/s  jpg
BM_UFlat/3                48947      48940      14363 1.8GB/s  pdf
BM_UFlat/4               441029     440835       1589 886.1MB/s  html4
BM_UFlat/5                39861      39880      17823 588.3MB/s  cp
BM_UFlat/6                18315      18300      38126 581.1MB/s  c
BM_UFlat/7                 5254       5254     100000 675.4MB/s  lsp
BM_UFlat/8              1568060    1567376        447 626.6MB/s  xls
BM_UFlat/9               337512     337734       2073 429.5MB/s  txt1
BM_UFlat/10              287269     287054       2434 415.9MB/s  txt2
BM_UFlat/11              890098     890219        787 457.2MB/s  txt3
BM_UFlat/12             1186593    1186863        590 387.2MB/s  txt4
BM_UFlat/13              573927     573318       1000 853.7MB/s  bin
BM_UFlat/14               64250      64294      10000 567.2MB/s  sum
BM_UFlat/15                7301       7300      96153 552.2MB/s  man
BM_UFlat/16              109617     109636       6375 1031.5MB/s  pb
BM_UFlat/17              364438     364497       1921 482.3MB/s  gaviota
BM_UFlatSink/0           108518     108465       6450 900.4MB/s  html
BM_UFlatSink/1           991952     991997        705 675.0MB/s  urls
BM_UFlatSink/2            26815      26798      26065 4.4GB/s  jpg
BM_UFlatSink/3            49127      49122      14255 1.8GB/s  pdf
BM_UFlatSink/4           436674     436731       1604 894.4MB/s  html4
BM_UFlatSink/5            39738      39733      17345 590.5MB/s  cp
BM_UFlatSink/6            18413      18416      37962 577.4MB/s  c
BM_UFlatSink/7             5677       5676     100000 625.2MB/s  lsp
BM_UFlatSink/8          1552175    1551026        451 633.2MB/s  xls
BM_UFlatSink/9           338526     338489       2065 428.5MB/s  txt1
BM_UFlatSink/10          289387     289307       2420 412.6MB/s  txt2
BM_UFlatSink/11          893803     893706        783 455.4MB/s  txt3
BM_UFlatSink/12         1195919    1195459        586 384.4MB/s  txt4
BM_UFlatSink/13          559637     559779       1000 874.3MB/s  bin
BM_UFlatSink/14           65073      65094      10000 560.2MB/s  sum
BM_UFlatSink/15            7618       7614      92823 529.5MB/s  man
BM_UFlatSink/16          110085     110121       6352 1027.0MB/s  pb
BM_UFlatSink/17          369196     368915       1896 476.5MB/s  gaviota
BM_UValidate/0            46954      46957      14899 2.0GB/s  html
BM_UValidate/1           500621     500868       1000 1.3GB/s  urls
BM_UValidate/2              283        283    2481447 417.2GB/s  jpg
BM_UValidate/3            16230      16228      43137 5.4GB/s  pdf
BM_UValidate/4           189129     189193       3701 2.0GB/s  html4

A=uday
R=sanjay
2015-07-06 14:21:00 +02:00

105 lines
3.2 KiB
C++

// Copyright 2011 Google Inc. All Rights Reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <string.h>
#include "snappy-sinksource.h"
namespace snappy {
Source::~Source() { }
Sink::~Sink() { }
char* Sink::GetAppendBuffer(size_t length, char* scratch) {
return scratch;
}
char* Sink::GetAppendBufferVariable(
size_t min_size, size_t desired_size_hint, char* scratch,
size_t scratch_size, size_t* allocated_size) {
*allocated_size = scratch_size;
return scratch;
}
void Sink::AppendAndTakeOwnership(
char* bytes, size_t n,
void (*deleter)(void*, const char*, size_t),
void *deleter_arg) {
Append(bytes, n);
(*deleter)(deleter_arg, bytes, n);
}
ByteArraySource::~ByteArraySource() { }
size_t ByteArraySource::Available() const { return left_; }
const char* ByteArraySource::Peek(size_t* len) {
*len = left_;
return ptr_;
}
void ByteArraySource::Skip(size_t n) {
left_ -= n;
ptr_ += n;
}
UncheckedByteArraySink::~UncheckedByteArraySink() { }
void UncheckedByteArraySink::Append(const char* data, size_t n) {
// Do no copying if the caller filled in the result of GetAppendBuffer()
if (data != dest_) {
memcpy(dest_, data, n);
}
dest_ += n;
}
char* UncheckedByteArraySink::GetAppendBuffer(size_t len, char* scratch) {
return dest_;
}
void UncheckedByteArraySink::AppendAndTakeOwnership(
char* data, size_t n,
void (*deleter)(void*, const char*, size_t),
void *deleter_arg) {
if (data != dest_) {
memcpy(dest_, data, n);
(*deleter)(deleter_arg, data, n);
}
dest_ += n;
}
char* UncheckedByteArraySink::GetAppendBufferVariable(
size_t min_size, size_t desired_size_hint, char* scratch,
size_t scratch_size, size_t* allocated_size) {
*allocated_size = desired_size_hint;
return dest_;
}
} // namespace snappy