[PlanetCCRMA] kernel 2.6.14 and Alsa 1.0.10 for FC3

Fernando Lopez-Lezcano nando@ccrma.Stanford.EDU
Sat Nov 19 11:55:02 2005


On Fri, 2005-11-18 at 22:02 -0800, Mark Knecht wrote:
> On 11/18/05, Fernando Lopez-Lezcano <nando@ccrma.stanford.edu> wrote:
> >
> > I'm running 2.6.14-0.7.rrt.rhfc4.ccrma and alsa 1.0.10 right now, but
> > I'm not sure if I want to mess everybody else's machines as well :-)
> >
> > -- Fernando
> >
> > [*] long answer: each cpu has its own timer and apparently they can
> > drift from each other as time goes by... Jack hops from processor to
> > processor depending on how things are scheduled, if it is in the same
> > processor from which it originally got the initial "time reference" all
> > is fine, if it is on the other processor eventually the time measurement
> > goes wrong and you get warnings that have no basis - lots of them. One
> > suggested "solution" is to pin jackd to one of the processors but that
> > is just a hack IMHO. Another would be to use a different timing source,
> > there is one but that one is more expensive in processor cycles.
> > Probably the only acceptable solution I've heard so far...
> >
> 
> So this only effects SMP and HT machines? It does not effect UMP?

I have no idea about HT (maybe the "fake" multiprocessing there uses the
same TSC for everything?). Come to think of it I don't know if I have
tested on HT machines for this problem. 

I think I did a test by booting into a UP kernel and all was well but
I'm not positive, I should repeat it. 

-- Fernando