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Date: Tue, 23 Nov 2004 15:45:02 +0200
From: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua>
To: Brian Fundakowski Feldman <green@freebsd.org>
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cc: freebsd-hackers@freebsd.org
Subject: Re: Tracing Disk Access
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On Mon, Nov 22, 2004 at 06:33:18PM -0500, Brian Fundakowski Feldman wrote:
> On Mon, Nov 22, 2004 at 04:22:54PM +0100, Hanspeter Roth wrote:
> > 
> > Hello,
> > 
> > I have set an idle timeout for the hard-disk. But when there is no
> > user activity there are frequent disk accesses.
> > How can one trace disk access?
> > I'd like to know the kind of access and on which files/directories/
> > nodes. I'd like to log on the console or on a memory disk file.
> 
> You should look to the MAC framework to provide you -- if not the entire
> solution -- at least insight into how and where you can do this.  If you
> were to do it at the disk device level, it would be a GEOM module, though.
> 

As I understood you suggested to insert controlling geom between a
consumer and a provider attached to each other.  Am I right that with
GEOM framework it is impossible to control if some data is read from
the buffer cache and it is only possible to control device strategy
calls?