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Date: Tue, 28 Jun 2011 14:54:49 -0700
From: perryh@pluto.rain.com
To: yuri@rawbw.com
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Cc: freebsd-hackers@freebsd.org
Subject: Re: How can process in STOP state consume 200% CPU?
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Yuri <yuri@rawbw.com> wrote:

> kill -9 doesn't kill it.

I think I've seen this before; it looks as if, since the process is
STOPped, the "kill -9" remains pending rather than being acted upon.
I _think_ you can make the process go away by doing a "kill -CONT"
after the "kill -9".

No idea how a STOPped process can continue to consume CPU, unless
in an infinite loop at elevated interupt level (and in that case
the "kill -CONT" may not work -- you may need to drop into kdb, try
to do some debugging and/or get a dump, and then reboot).