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Date: Fri, 15 Oct 2004 21:27:02 -0600
From: Scott Long <scottl@freebsd.org>
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To: Andrey Chernov <ache@nagual.pp.ru>
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cc: David Schultz <das@freebsd.org>
cc: current@freebsd.org
Subject: Re: Stable panic on shutdown: swapoff: failed to locate N swap
	blocks
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Andrey Chernov wrote:
> On Fri, Oct 15, 2004 at 08:39:34PM -0600, Scott Long wrote:
> 
>>FWIW, I think that doing a swapoff in the shutdown path is just asking
>>for trouble.  Fixing whatever bug this is would of course be nice, but
>>the need for swapoff here is a hack and only opens up up to problems.
> 
> 
> I agree. It looks like sort of race happens. Application (cvsupd) can be 
> killed, but its inodes activity delayed by softupdates a bit more (just 
> raw guess). I see no useful purpose to call swapoff(8) at shutdown stage, 
> correct me, if I am not right.
> 

The swapoff hack is needed so that the swapper will close the swap
device and remove the reference on the gmirror instance, which in turn
allows gmirror to know that it can close itself down.

Scott