[plug] unkillable proces

[Bernard Blackham]

On Sun, Jul 31, 2005 at 11:33:10AM +0800, William Kenworthy wrote:
> I have an unkillable process using all spare cpu cycles.  It just shrugs
> off kill -9 ...

What state does ps show it as being in? If it's a zombie (Z), then
it shouldn't be chewing up CPUs. Zombies come about because their
parents don't clean up properly. If its parent dies, it should
disappear too. If it's in the D state, it's stuck talking to the
kernel, and "ps -o wchan <pid>" will tell you whereabouts.
strace'ing it may provide some more information too. It might be
waiting on a network filesystem that disappeared, but again,
shouldn't be sucking 100% CPU.

Also, if it's a kernel thread, then there's probably no hope without
a reboot, unless the kernel thread is linked to something (eg, a
network driver), in which case cycling the
interface/filesystem/whatever, and maybe unloading/reloading the
module may help.

You may be able to just stop it in its tracks by sending a SIGSTOP.

> Is there anyway to kill it or is it reboot?  Its not a drama except some
> long running jobs (weeks) are running at -19 and are not getting a look
> in.

What kind of jobs are they? Could they be saved with cryopid[1]? If
not, let me know and I'll see what I can do :)

Bernard.

[1] http://cryopid.berlios.de/

-- 
 Bernard Blackham <bernard at blackham dot com dot au>