[PlanetCCRMA] added: ALPHA version of Planet Core components for FC2

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Fri Jun 25 10:02:01 2004

On Fri, 2004-06-25 at 09:41, Steve Harris wrote:
> On Fri, Jun 25, 2004 at 08:30:06 -0700, Fernando Pablo Lopez-Lezcano wrote:
> > > That does sound exactly like denormals. Are you running a P4 by any
> > > chance?
> > 
> > Yes, P4 1.7G on my laptop. 
> The denomral handing on P4's seems to be much more expensive, and it
> appears to react badly to small numbers that are not quite denormals.
> > > I've only tried AMS and jamin (debugging) with the RT kernel, with the
> > > stock fedora one I've run a variety of stuff, it xruns occasioanlly,
> > > as you would expect, but no storms.
> > 
> > That is interesting and something I should try. I have not actually
> > tried to run things in the stock kernel as I would have to run them as
> > root, and it is not possible to build the realcap kernel module :-( How
> > long are the xruns you see? Should I assume that the tests in the stock
> > kernel were done as root with SCHED_FIFO? (jackd -R).
> I've done a bit of testing as root, but mostly running jackd as me.
> I've just run 2x1024 AMS feeding meterberidge and jamin and I was able to
> use them all nomrally for a quite a while without xruns (other than when I
> started jack apps).
> After sitting there for a bit, I got a 78ms xrun, possibly when I switched
> virtual desktops.
> At 2x512 I get xruns of about 2-8ms every few seconds.
> At 2x4096, running as a user it is good enough for deugging, no xruns so
> far (phew!), though not exatly low latency :)

Thanks for the numbers, gives me a feel of what you are seeing. 

> I tried running it as root (2x1024) this time I got the
> delay of 18841.000 usecs exceeds estimated spare time of 6248.000; restart ...
> storm, as soon as I run jamin and AMS, as I was seeing with the CCRMA
> kernel, but I dont remeber seeing that before.

So it would seem the weird problems happen when the processes run

Could jamin be also triggering denormals? In tests I did yesterday I
only saw the storms with gverb, but then again they were not very long
tests and it may have been just luck. 

> > When you say stock kernel you mean the one originally shipped with FC2,
> > right?
> Right now I'm running 2.6.6-1.435, from FC2.

Ah, ok, so it is almost in sync with the Planet CCRMA one. I thought it
may be much earlier and thus more different. 

-- Fernando