Subject: Re: kern/8679: kill -9 fail to kill some processes
To: None <netbsd-bugs@netbsd.org, gnats-bugs@netbsd.org>
From: Christoph Badura <bad@oreilly.de>
List: netbsd-bugs
Date: 10/25/1999 18:34:57
p99dreyf@criens.u-psud.fr writes:
>>Description:
>Some processes (mountd, httpsd, login...) crash and are not killable by
>a kill -9. 

When a process is sleeping at an uninterruptable priority no signals will
be delivered to it until it wakes up.  After it wakes up, the SIGKILL will
terminate the process.

>Here is ps -axl output for thoses processes
> 0 25546     1   0 -18  0   136    0 uvn_ge DWs  ??    0:00.12 mountd

That's only one process.  Are the others also waiting on "uvn_ge"?
And this process is sleeping at an uninterruptible priority.

Did you get disk errors before this?  Are you using NFS?

>>How-To-Repeat:
>No idea about how thoses processes appear. As the system is running, new 
>unkillable zombies processes appear.

These aren't zombie processes.  A zombie process is a process which has
exited and released all its resources.  It is now just occupying a process
table slot so that the parent process can collect the exit status.
Zombies are marked with a Z in state column of ps output.

-- 
Christoph Badura					www.netbsd.org

	Anything that can be done in O(N) can be done in O(N^2).
	-- Ralf Schuettau (after looking at a particular piece of code)