[PlanetCCRMA] Enabling low latency in FC2

Mark Knecht markknecht@comcast.net
Tue Sep 28 17:46:01 2004


Fernando,
   I want to check as to whether there are any system values I need to
enable to get low latency and root level capabilities as a normal user.
Currently I cannot start QJC as a normal user using jackstart as the
start method. I can run QJC with jackd.

   I have the 2.6.8.1 ll kernel running with Alsa 1.06. Unfortunately I
have not set up access to email on the Planet side yet so it is
difficult for me to provide output today. Hopefully I'll have that
tomorrow.

I have enabled the items in the email you directed me to:

kernel_preemption == 1
voluntary_preemption == 3
threaded IRQ for the ATI chip == 0

(It dawns on me right now that if these values didn't stick after my
reboot that possibly one or more were not set. I'll check next time I go
over.)

In rereading the email right now I see that the sysrq == 1 was not
marked optional. Is that a requirement? I'll try that when I go back
over also.

Right now, even as root, if I run jack with moderate latency settings of
512/2 using my USB mouse is causing lots of xruns so clearly something
is not right.

As a normal user QJC tells me the kernel doesn't provide capabilities so
clearly somethign seems like it needs enabling.

I may try your xrun logging feature and see what it tells me.

Thanks in advance,
Mark