Hi Douglas, hi Spencer, I run the test case with the feature/Euler1D branch with SumFac : Time-integration : 18.7779s Total Computation Time = 21s This make a difference! no tuning: Time-integration : 32.797s Total Computation Time = 35s Also no too bad! I already notice the orphaned code that you removed. Was this the solution of my speed issue, or was it because I used the release version 4.3.1.? Cheers, Helmut ________________________________ Von: Douglas Serson [d.serson@gmail.com] Gesendet: Donnerstag, 19. Mai 2016 15:40 An: Kühnelt Helmut Cc: Sherwin, Spencer J; nektar-users Betreff: Re: [Nektar-users] EulerCFE - performance issue & MPI problem Hi Helmut, I pushed some changes to the feature/Euler1D branch which should make this simulation somewhat faster. It would be great if you could test that to see if it helps with your problem. Cheers, Douglas 2016-05-18 13:29 GMT+01:00 Kühnelt Helmut <Helmut.Kuehnelt@ait.ac.at<redir.aspx?REF=VaiQVChfgkaSHMIK8V1w5MoxFXPMoGbSCKCoUTD34VlEJI4k8n_TCAFtYWlsdG86SGVsbXV0Lkt1ZWhuZWx0QGFpdC5hYy5hdA..>>: Hi Spencer, hi Douglas, Indeed, using Collections (auto => SumFac) definitively helps: Total Computation Time = 95s (180s before) I noticed that the code runs single threaded, even though Boost_USE_MULTITHREADED is ON and OpenBlas is compiled as multi threaded. Any hints on that? Cheers, Helmut ________________________________ Von: Sherwin, Spencer J [s.sherwin@imperial.ac.uk<redir.aspx?REF=T8yT6PfzUIHmdHW76qXpUm3oNtBk-gKf_xC1CdXkNYpEJI4k8n_TCAFtYWlsdG86cy5zaGVyd2luQGltcGVyaWFsLmFjLnVr>] Gesendet: Mittwoch, 18. Mai 2016 10:25 An: Kühnelt Helmut Cc: nektar-users Betreff: Re: [Nektar-users] EulerCFE - performance issue & MPI problem HI Helmut, I am building with Release mode and nothing else in particular. I happen to have MPI turned on but I do not think that will make a difference. One thing that might be worth checking is the use of openblas. I have had trouble with openblas in the past for small matrix sizes. The compilation I used will have been using the default installation in /usr/lib/libblas.a. I guess Douglas’ test will have used the Framework of Mac OS X. However looking at the set up on the compute module I do seem to have openblas loaded (@Chris: Could you confirm what version of openblas is running on Victoria Other configurations are: library gcc 4.9.2 boost 1.58 - installed from a module Do you have another machine/laptop we could turn this test on? Cheers, Spencer. PS I had a time step of 1e-6 and attach my .xml file below