[ardour-users] Jack uses 100% CPU and can't be killed

[ross at lug.udel.edu]

On Tue, Nov 30, 2004 at 08:18:45AM -0800, Mark Knecht wrote:
> On Tue, 30 Nov 2004 10:58:33 +0000, Ben Edwards <funkytwig at gmail.com> wrote:
> > When I run jack with qjackctl it coplains about ALSA/midi/patchbay.  I
> > went on IRC and as a result tried to start jack anyway.   It then
> > consumed 100% cpu.  I couldent run top or ps!  In fact I couldent even
> > shut down the PC properly - I had to hold my finger on the power
> > button for 10 seconds to do a hard shutdown.
> > 
> > BYW are the error messages loged to a file - I cant even copy/paste
> > them from the message window.

I can pretty much guess what's going on.  You're running a 2.6 kernel
right?  I had exactly the same symptoms and decided to stick with 2.4.

I'm not too sure of what's going wrong, but under recent 2.6 kernels,
when a realtime application runs, it consumes tons of CPU and locks up
a lot of system function.  The odd thing --- I could still use any
browsers or shells I had already started.  Any file access would lock
a process solid in an instant.

Like I said - I gave up, went back to 2.4.  The Jack FAQ has some
notes on Jack maybe working with LD_ASSUME_KERNEL=2.4.19.  I don't
remember if I had any luck with that.  I assume no, else I'd have
stuck with 2.6.

-- 
Ross Vandegrift
ross at lug.udel.edu

"The good Christian should beware of mathematicians, and all those who
make empty prophecies. The danger already exists that the mathematicians
have made a covenant with the devil to darken the spirit and to confine
man in the bonds of Hell."
	--St. Augustine, De Genesi ad Litteram, Book II, xviii, 37