[PlanetCCRMA] 2.6 RT progress :)

Steve Harris S.W.Harris@ecs.soton.ac.uk
Fri Aug 27 06:22:02 2004


OK, things are starting to make more sense.

1st, the problem I was seeing with ardour appears to be an ardour problem,
looking at an strace there someting really odd going on. All othe apps
start OK, and the zobification I was seeing looks like effect, not cause
of ardour crapping out. [embarassing admission] if I start ardour without
a session file it loads ok *cough*.

2nd, as I suspeicted power management does seem to cause problems, if I do
echo "performance" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
I can start and stop jackd, start and stop jamin, jack-rack's full of
plugins etc. without the dreaded "exceeds estimated spare" messages. At
least over a test of about 10 cycles.

With the govenor set to userspace (powernowd in this case) just starting
jackd can be enough to start the scrolling messages, and usually after
running an app or two I get them. They seem to be triggered by CPU
frequency transitions, but I suspect theres something more complex going
on.

What I still dont understand is why I can get hundreds of these really
long sounding delays (some are 10ms+), with hardly any XRUNs. My suspicion
is that jackd's logic for detecting this condition is not right.

- Steve