2010/4/21 Colin Guthrie <gmane@xxxxxxxxxxxxxx> > 'Twas brillig, and Raymond Yau at 21/04/10 01:30 did gyre and gimble: > > 2010/4/19 Daniel Chen <seven.steps@xxxxxxxxx> > > > >> but, like > >> Lennart suggests, these are by no means *caused* by PulseAudio. > >> > >> Best, > >> -Dan > >> > >> > > There are other factor affecting CPU usage significantly > > > > 1) the number of pulseaudio clients connected to PA server (i.e. number > of > > audio stream need to be mixed ) > > 2) the accuracy of system timer and the clock of the sound chip > > 3) the latency requirement of the different PA clients > > 4) the resampling method > > 5) the cpu loading of the system > > 6) the period time/period size selected by PA server to configure the > alsa > > driver > > > > why do you ruled out the cause ? > > > >>> If you use "pacat" you can play audio with almost zero CPU > > usage > > > > do you get the zero CPU usage in Ubuntu 9.04/Ubuntu 9.10 with pacat on > your > > machines ? > > The pacat support for proper latency adjustment is only available in > more recent PA versions (with some , so chances are the older distros > wont have them (although I believe a 9.10 version of 0.9.21+stable-queue > exists somewhere. > > > These commits from stable-queue are certainly needed: > > commit 19fa81bf1375032cb1a27c7715a28a52b238d4cb > Author: Lennart Poettering <lennart@xxxxxxxxxxxxxx> > Date: Thu Feb 18 01:54:51 2010 +0100 > > pacat: always fully fulfill write requests > > Make sure we always fulfill write requests from the server. If we don't > the server won't ask us again and playback will stay stuck. > > > > https://tango.0pointer.de/pipermail/pulseaudio-discuss/2010-February/006611.html > > > and this one (although it's not problematic for playback): > > commit b2e9fb6f6e12a3eab8a41c67017507e60d616e2a > Author: Lennart Poettering <lennart@xxxxxxxxxxxxxx> > Date: Sun Feb 21 21:09:26 2010 +0100 > > pacat: pass buffer_attr to recording streams too > > Pointed out by Colin Guthrie. > > > > https://tango.0pointer.de/pipermail/pulseaudio-discuss/2010-February/006698.html > > > -- > > Colin Guthrie > is it possible to provide some figure to compare the CPU usage of PA when using pacat, paplay and aplay on your machine ? the problem of Shuang He seem related to upmixing of stereo to surround71 >> sink: 0 <alsa_output.pci-0000_00_1b.0. analog-surround-71> volume: 0: 100% 1: 100% 0: 0.00 dB 1: 0.00 dB balance 0.00 muted: no current latency: 444.25 ms requested latency: 31.25 ms sample spec: s16le 2ch 48000Hz channel map: front-left,front-right Stereo resample method: speex-float-3 module: 8 client: 7 <ALSA plug-in [mplayer_2010_0414]> _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
