On Mon, 30 Mar 2015 13:55:55 +0200 Jan Blechta <[email protected]> wrote:
> On Mon, 30 Mar 2015 11:34:19 +0000 > Anders Logg <[email protected]> wrote: > > > See this question on the QA forum: > > > > http://fenicsproject.org/qa/6875/ubuntu-compile-from-source-which-provide-better-performance > > > > The Cahn-Hilliard demo takes 40 seconds with 1.3 Ubuntu packages and > > 52 seconds with 1.5+ built from source. Are these regressions in > > performance or is Johannes that much better at building Debian > > packages than I am building FEniCS (with HashDist). > > > > PS: Looking at the benchbot, there seem to have been some > > regressions in the timing facilities with the recent changes: > > Ok, I will look if something can be done with common-timing-cpp > regression. I have a guess what causes that. I haven't profiled it rigorously yet but it seems that most of the regression is due to switching from gettimeofday() from sys/time.h to boost::cpu_timer. Anders, is there any strong reason for improving the current timings? Isn't it fast enough? I don't think that we use Timer class in any loop such tight that this slowddown would have effect and I would hardly expect users doing it. Jan > > Nevertheless, please note slowdown of la-vector-access-cpp. > http://fenicsproject.org/benchbot/la-vector-access-cpp_last_five_years.png > > It could be a cause of the regression of Cahn-Hilliard demo. You could > even try running it with uBLAS/UmfpackLUSolver on both versions to see > whether the problem is in PETSc/wrappers. > > Jan > > > > > http://fenicsproject.org/benchbot/ > > > > -- > > Anders > > _______________________________________________ > fenics mailing list > [email protected] > http://fenicsproject.org/mailman/listinfo/fenics _______________________________________________ fenics mailing list [email protected] http://fenicsproject.org/mailman/listinfo/fenics
