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Date: Mon, 05 Sep 2005 12:24:27 -0600
From: Scott Long <scottl@samsco.org>
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To: Nikhil Dharashivkar <nikhildharashivkar@gmail.com>
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Cc: freebsd-hackers@freebsd.org, freebsd-scsi@freebsd.org
Subject: Re: Adding new option to ktrace
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Nikhil Dharashivkar wrote:
> Hi,
>    i want to hack the ktrace system call. Basically, I want to monitor
> scsi disk IO through dastrategy() routine.
>     It seems that kern_ktrace.c implements different functions for
> ktrace options like -tc / -ti ... etc (see man page). So, is it
> possible to add new option for disk IO with new structure object
> containing disk io information which will be pass to
> ktr_submittrequest thr' ktr_request structure.
>          Will data will be written correctly in ktrace.out and will
> kdump analyze that ?
> 
> 
> 

What are you trying to monitor?  Would the existing devstat interface
work?

Scott