Subject: Re: file i/o monitoring
To: Ketil Danielsen <>
From: Manuel Bouyer <>
List: tech-userlevel
Date: 11/19/2004 18:48:45
On Thu, Nov 18, 2004 at 09:08:22AM +0100, Ketil Danielsen wrote:
> I'd like to know the I/O activity towards the filesystem.  I'd like my 
> disk to stop spinning, to save battery power, but one of the processes 
> keeps waking it up, and I do not know which one.  The 
> equivalent of filemon (which exists for Linux, but I do not run 
> emulation) would be nice -- but any suggestion on how to pin down the 
> offending processes would be appreciated.  Thanks.

You can try fstat, to see which file are open for write.

BTW, to minimise disk access, make sure to mount filesystems noatime,nodevmtime
and remove the at entry from the crontab (it will generate a write to
/var/cron/log every 10 minutes)

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference