On Dec 28, 2007 9:46 AM, Karsten Wiese <annabellesgarden@xxxxxxxx> wrote: > Am Freitag, 28. Dezember 2007 schrieb Jacob Lee: > > I'm using an M-Audio Transit usb soundcard with the kernel 2.6.22-rt, > > as packaged by ubuntu. I'm running jack right now with -p 3 -n 512, > > and I still get xruns, typically of values less than .03ms, every few > > minutes. > > You can try increasing the client timeout, i.e: > $ jackd -R -P60 -t200 ... > helps here using kernel 2.6.24-rcx. > Interesting. The default timeout is 500; I've tried lowering it slightly and raising it to 1000 or 2000 without effect. > (( > jackd calls poll() with a timeout value of a period's ms each time > it triggers the external clients. Linux's poll() call can timeout at > (specified timeout - jiffy). IMHO either linux needs to be fixed to > implement posix poll() timeout handling, or jackd has to supply > (a period's ms + a jiffy's ms) as parameter for the poll() call. > )) > Karsten > Ah. These xruns occur even with no jack clients running, so this option might not change anything. Another interesting data point is that changing the values for -p and -n increase or decrease how often xruns appear, but they are always of extremely low values (.020-.050 ms). One would think that adding a few milliseconds of extra latency would eliminate such small xruns; or, reducing the latency would cause xruns of much longer duration. I should also mention that I occasionally get the message "delay of 10698.000 usecs exceeds estimated spare time of 10547.000; restart ..." (with varying values for the delay), but I've assumed this is just a manifestation of the same issue; at any rate, such messages happen far less often than the xruns. -- Jacob Lee artdent@xxxxxxxxx _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/mailman/listinfo/linux-audio-user
