On 08/14/2012 10:16 AM, Goldy wrote: > Le 13/08/2012 19:40, Peter Meerwald a ?crit : >> Hello, >> >>> At this point, on system wide running, pulseaudio uses 34% cpu when it >>> idles, when music is played, it uses 42%. It's a lot on the 700 mhz >>> raspberry pi cpu, I'm pretty sure there is a way to decrease it, but >>> documentation don't talk about this point. >> that sounds way too high... >> unfortunately, the Broadcom CPU does not support ARM NEON >> >> I found that the ARM assembler code does not improve performance on a >> Cortex-A8, maybe it also helps to disable on the Raspberry? >> >>> I don't use the raspberry internal sound card, I plugged a little usb >>> Terratec aureon sound card, it works very well excepted the cpu usage... >> would be interesting to find out where the CPU time is spent; in >> PulseAudio or somethere in the USB stack... >> >> do you have a chance to do some profiling? maybe you can get oprofile to >> work? >> >> regards, p. >> > Unfortunately, oprofile seems not to be working on raspberry... or I > didn't use it properly. > > I followed the instructions here > http://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/Developer/OProfile > and I always get this : > >> % sudo opreport -l /usr/bin/pulseaudio >> error: no sample files found: profile specification too strict ? > If you have any advice, it would be welcomed. > > Thanks again > > Christophe > _______________________________________________ > pulseaudio-discuss mailing list > pulseaudio-discuss at lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/pulseaudio-discuss In profiling with oprofile on CuBox the code that is hogging cpu is the Speex resampler. I am currently trying to figure out how to get pulseaudio open without triggering the resampler. There are about 3 tests in pulseaudio which check for the need to resample. If any of them evaluate as true, resampling kicks in. To avoid resampling: 1. you can't use variable sample rate 2. the channel maps have to match 3. the sample rate has to match
