[linux-audio-user] Re: ingo's 2.6.x patches

[Dave]

On Tuesday 07 September 2004 06:45, Eric Dantan Rzewnicki wrote:
> Eric Dantan Rzewnicki wrote:
> > Eric Dantan Rzewnicki wrote:
> >> Eric Dantan Rzewnicki wrote:
> >>> For anyone who, like me, missed most of the past month or two of
> >>> discussions, this is where Ingo's 2.6.x patches live:
> >>> http://people.redhat.com/mingo/voluntary-preempt/
> >>> Thanks to whoever posted the kernel-traffic link. I almost feel
> >>> caught up to reality now. 8-]
> >>
> >> Uhhhmmm ... anyone know if I want this:
> >> http://people.redhat.com/mingo/voluntary-preempt/diff-bk-040828-2.6.8.1.
> >>bz2 or this:
> >> http://people.redhat.com/mingo/voluntary-preempt/older/voluntary-preempt
> >>-2.6.8.1-P9
> >
> >          ^
> > Gaaahh.  | That's the one, I think. Compiling new kernel .deb at the
> > moment.
> >
> >> ???
> >> (maybe I should just go to sleep and deal with this tomorrow.)
>
> Ok ... I've got this installed now. recompiled the realtime lsm and
> recompiled alsa-drivers.
>
> http://people.redhat.com/mingo/voluntary-preempt/ANNOUNCE-voluntary-preempt
>
> speaks of setting /proc/sys/kernel/voluntary_preemption to 1 to turn it
> on ... trying this I still have the audio glitches and ecasound reports
> xruns. I noticed when the system came up this was set to 3 by default. I
> tried setting it back to 3, but still xruns. The audio glitches seemed
> to sound a little better ... but, I'm getting a little punchy and the
> work week is nearly upon me. I'll have to test more next weekend.
>
> have more options been added to the /proc/ interface for voluntary
> preempt since the announcement above?
>
I think the following is still correct - This is what i use with a slightly 
earlier patch.

To get the lowest latency you have to  (echo 0 > /proc/irq/?/?/threaded) 
where ? is the soundcard irq and the rtc irq.  

eg echo 0 > /proc/irq/10/ICE1712/threaded
&  echo 0 > /proc/irq/8/rtc/threaded

Dave

> I've seen some mentions of configuring alsa with debugging info. Is
> there a brief explanation somewhere of how to best help with weeding out
> the 2.6.x latency problems?
>
>
> Thanks,
> Eric Rz.