On Fri, Dec 1, 2017 at 6:52 PM, Khem Raj <[email protected]> wrote: > > >> > >> > I wonder if gcc could be initiated to see if it can vectorize the > code, > >> > here > >> > have you tried setting cmdline options or may be pragma hints > >> > > > > I've sent patches like these to some projects. If I remember correctly > first > > one was jack2 [1]. For that I wrote some performance tests [2] and tested > > vectorizing either but with disappointing results. This is ~ a year ago > and > > I think intrinsics are still the option performing better. > > > > [1] > > https://github.com/jackaudio/jack2/commit/77bb8be12e0d856fbc004cf57185ab > 36a2df04c2 > > [2] > > https://github.com/jackaudio/jack2/commit/c32b823860bc8e887774ab10bc3e9b > d76e85e3f3 > > interesting. does it mean that vectorization sucks in gcc form arm ? > and works ok on other architectures > I am not using other arches than ARM so I cannot help you here.
What I can say is that this patch together with setting fluidsynth to multi threaded operation [1] helped me to play MIDI arrangements with >20 tracks on Raspi3 without audible issues. Before it was a nightmare: Output was distorted totally and XRUNS reached numbers > 1000 very soon. A bit off-topic (but only a bit :) At the moment I am writing an extension to qjackctl: Some chart for so called DSP performance and XRUN frequency to gather reproducible numbers. So I can see exactly what change is an enhancement and how much it increases performance. Once this is done I plan to send this patch (and maybe others) upstream. I could try vectorizing once again then. Ahh - maybe I should mention: The patch causes effect only for fluidsynth in multi threaded mode. [1] https://github.com/schnitzeltony/fluidsynth-dssi/commit/bad09c6f5c5508c5f5330aa5188510f975e50c50 Cheers Andreas -- _______________________________________________ Openembedded-devel mailing list [email protected] http://lists.openembedded.org/mailman/listinfo/openembedded-devel
