Hi, It might be an issue with cache lines, using shared libs memory layout might fit better to your processor-caches
Would be interesting to verify performance on different architecture. Regards, Frank On 25.01.2015 12:44, Marcus Pollice wrote: > > > Marcus Pollice > On 22.12.2014 03:20, Mathieu Trudel-Lapierre wrote: >> >> I don't think there would be very many patches that are meant to improve >> performance in our patch set (note, I did not check). > That was a good assumption. Although some patches looked suspicious I > ultimately found that these patches don't materially affect performance. > More about that below. > >> You may also which to check what are all >> the compiler options coming from dpkg-buildflags used in the build... > That was a good idea indeed, but there was nothing out of the order > coming from there. Also since openssl writes the compile options to the > console when running the benchmarks I could test most of these before to > have no real effect. > >> I would suggest using the source package as a base >> and using debuild / chroots / PPAs to build your custom package, that >> way you'd benefit from the same performance unless your custom changes >> impact them in some way, with the least amount of effort. >> > Ultimately I used the Debian way of building to reproduce the same > performance level as the built-in packages. Then I started playing with > doing certain steps of the compilation manually vs automated building. > When I got a build with the patches applied and the same low performance > I was getting before I knew it was not the patches. I then dissected the > buildlog and at some point I noticed the major difference is that the > built-in version will be compiled with shared libraries. > > This is indeed the root cause for the performance difference I found. > The versions using shared libraries are indeed faster than a static > build (at least for the small data sizes). This is completely unexpected > to me. It is also somewhat unsatisfying as I now know the cause but > don't quite understand it. > -- Best regards - Mit freundlichen Grüßen - 谨致问候 Frank Rehberger, Berlin, Germany Phone: +49-173-205-7118 frank.rehber...@web.de -- Ubuntu-devel-discuss mailing list Ubuntu-devel-discuss@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss
