Hello HATAYAMA-san, On Tue, 03 Jul 2012 12:07:27 +0900 HATAYAMA Daisuke <d.hatayama at jp.fujitsu.com> wrote: > This patch series add snappy compression support, applied on top of > v1.4.4. snappy is fast compressoin algorhythm like lzo, but it's more > optimized than lzo on x86 machines and some others. > > A lot of benchmark is available on the web. Here I only point at my > benchmark I posted a few weeks ago, > > - http://lists.infradead.org/pipermail/kexec/2012-June/006425.html > > where snappy shows mostly as good performance as simple copying on > the worst case that input data increases its data size during > compression; this means we can use snappy with mostly NO risk. > > How to get snappy libraries: > > 1) Use yum framework to get snappy and snappy-devel packages, or > > 2) Visit official website: http://code.google.com/p/snappy/, > download snappy-<version>.tar.gz and then build it. > > How to build makedumpfile with snappy support: > > Do make as follows: > > $ make USESNAPPY=on Thank you for your work. I will merge your patches into the next version with small addition: diff --git a/README b/README index ae986d1..638b111 100644 --- a/README +++ b/README @@ -45,6 +45,9 @@ 6.Build with lzo support: # make USELZO=on ; make install The user has to prepare lzo library. + 7.Build with snappy support: + # make USESNAPPY=on ; make install + The user has to prepare snappy library. * SUPPORTED KERNELS This makedumpfile supports the following kernels. In addition, I did brief performance test with your patches: - The source data is a vmcore saved on the disk, it might be sparse data. - makedumpfile writes dumpfile to the same disk as the source data. - execution time is average of 5 times. | source | zlib | LZO | snappy ------------------------+---------------+-------------+-------------+------------- size (byte) | 5,107,498,116 | 242,398,239 | 309,549,499 | 487,542,710 compression ratio(%) | --- | 4.75 | 6.06 | 9.55 execution time (sec) | --- | 143 | 49.6 | 51.2 It seems that LZO still has worth in the case that good compression ratio is expected, as you said in your benchmark report. Thanks Atsushi Kumagai > --- > > HATAYAMA Daisuke (8): > Add manual description > Add help message > Add uncompression processing > Add compression processing > Notify snappy unsupporting when disabled > Add snappy build support > Add command-line processing for snappy > Add dump header for snappy > > > Makefile | 5 +++++ > diskdump_mod.h | 2 ++ > makedumpfile.8 | 9 +++++--- > makedumpfile.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++------ > makedumpfile.h | 3 +++ > print_info.c | 16 ++++++++++----- > 6 files changed, 80 insertions(+), 15 deletions(-) > > -- > > Thanks. > HATAYAMA, Daisuke
