Re: Squid in Stat D

> I was using the latest rpm of 1.1 and it would end up in
> stats D "uninterunptible sleep" There was no way to kill the process
> so O had to reboot. It would do this after a few hours under light load.

This is always a kernel or device driver level problem. It means the
kernel was doing something dangerous and had to wait for a resource,
but was never woken up. The kernel should never do this unless it is
sure the resource will become available quickly.

You can, however get chains of these where one process is deadlocked
and the others are waiting for it.

Squid is an application program and may have behaviour which is a co-
factor, but no application should be able to create this effect on a
working system. For most unixes, the wchan field in ps -l will tell
you the resource that is busy; for Linux it will tell you the kernel
routine where the wait is occurring, which unfortunately gives less
information.

-- 
David Woolley - Office: David Woolley <djw@bts.co.uk>
BTS             Home: <david@djwhome.demon.co.uk>
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