[linux-audio-user] 2.6.15.4, realtime-lsm, jackd -R, system performance down!

I just compiled a vanilla kernel 2.6.15.4 in my G3 powerpc. Also I compiled, installed and loaded the realtime-lsm module and I started to play with jackd -R and some jack enabled applications. If I start jackd without realtime, everything runs nicely, of course with some xruns when I switch windows, manipulate GUIs and such. This is more or less what I expected. But then I run jackd realtime using qjackctl. I start amsynth and it takes a bit longer to load but then runs without a mess. Sound is clean, no artifacts, no xruns. Then I try horgand. It takes a lot for it to load, then it sounds nicely, I get no xruns, but my X Window system becomes unresponsive. Later I try zynaddsubfx. It takes half an hour to open, and then it kills qjackctl, leaving the jack server running. Meanwhile top shows that zynaddsubfx is taking 35% of memory, and qjackctl and jackd 25% each. Could this be an issue with the applications, with the kernel, with the realtime-lsm module, with priority of my X Window session? I must insist this only happens when jackd is run with the -R option. Is it true that realtime-lsm is deprecated? How do I enable realtime preemption on a 2.6.15? Any ideas welcome. Cordially, Ismael -- Dropping science like when Galileo dropped his orange http://lamediahostia.blogspot.com/ http://www.flickr.com/photos/ivalladt/