[LAU] Jack frequently crashes when running LinuxSampler + Qsynth

[Jonathan E. Brickman]

> Upon restarting Jack, everything's happily back to normal, until the 
> crash happens again. I checked with the system monitor, and the resource 
> usage is well within limits - max of ~80% CPU/core, and less than 50% of 
> RAM being used at any point of time.
>   
Greetings, Guru.  80% of CPU per core is very high indeed, for audio 
processing.  When I run 40% on a core running an audio generator (SF2, 
sampler, or synth), I expect clicks and worse.  What GHz is your CPU 
running, and what is the FSB and type of your RAM?  If you have high GHz 
but slow RAM, that's just about exactly the same as low GHz.

I also wonder if you have background software conflicts somewhere, or 
hardware conflicts, or something else.  The last time I tried Ubuntu it 
kept huge UI/WM/API things in the background at all times, and even 
though 'top' claimed they were eating no CPU, I strongly believe that 
the kernel itself (not listed in top) was working hard fighting them 
back all the time.  The difference I saw on 1GHz hardware running 
AVLinux, Sabayon, and Linux Mint tends to bolster this theory. 

If it helps, I'm on an AMD Phenom I X4, 4G RAM, nVidia motherboard with 
ACPI turned off, VG but not too pricey Audiotrak HD2 sound card. 

Also, my performance jumped a lot after I turned ACPI off.  Can you turn 
ACPI off on a Mac?

Last but not least, you are using the built-in sound system.  Anyone 
know if it is any good?  I don't mean quality, I mean host-based 
processing.  If it does a lot of host-based processing, that's a next 
issue to address.  It'll be better to address it anyhow, you'll wear out 
the 1/8" stereo jack in your laptop rather quickly if you don't.

J.E.B.