Hi guys, Here is what I have:
$ cat /proc/asound/timers G0: system timer : 1000.000us (10000000 ticks) G3: HR timer : 0.001us (1000000000 ticks) Client sequencer queue 0 : running P1-0-0: PCM playback 1-0-0 : SLAVE P1-0-1: PCM capture 1-0-1 : SLAVE Ralf, you do not benefit from a high res timer. See how much more precise the HR timer is from the output above. Check which snd timer you have loaded: $ lsmod | grep timer snd_hrtimer 2148 1 snd_timer 17408 3 snd_hrtimer,snd_seq,snd_pcm Of course, your h/w should have a HR timer: $ ll /dev/hpet crw-rw---- 1 root audio 10, 228 2009-11-05 12:59 /dev/hpet you can specify the clock source to jackd: $ jackd --help ... [ --clocksource OR -c [ c(ycle) | h(pet) | s(ystem) ] ... J. --- On Sat, 11/7/09, Ralf Mardorf <[email protected]> wrote: > From: Ralf Mardorf <[email protected]> > Subject: Re: [LAD] timers > To: "Emanuel Rumpf" <[email protected]> > Cc: [email protected] > Date: Saturday, November 7, 2009, 7:04 AM > Emanuel Rumpf wrote: > > Hi > > > > I'm confused about all the timers. > > > > There is: > > - system timer > > - hpet (high precision event timer) > > - hr-timer (high resolution timer) > > - rtc (real time clock) > > - cyclic (what's that? a coded loop?) > > - anything else ? > > > > > > What is the relation of all these ? > > Which hardware devices are actually used by those ? > > Which is the prefered timer for sequencing ? hr-timer > / rtc ? > > > > If hardware is fine with Linux real-time audio, if I > understand > correctly, the preferred timer for MIDI sequencers is > (should be) system > timer at ! 1000 Hz ! For my hardware, that has got problems > with > real-time audio, it's PCM playback and PCM capture. Using > this timers > MIDI jitter will decrease a little bit. > > This is the output I get for 64 Studio 3.0-beta3: > > spinymouse-s...@64studio:~$ cat /proc/asound/timers > G0: system timer : 1000.000us (10000000 ticks) > P0-0-0: PCM playback 0-0-0 : SLAVE > P0-0-1: PCM capture 0-0-1 : SLAVE > Client sequencer queue 0 : stopped > _______________________________________________ > Linux-audio-dev mailing list > [email protected] > http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev > _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
