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To: Alexander Nyberg <alexn@telia.com>
Cc: Miles Lane <miles.lane@comcast.net>, linux-kernel@vger.kernel.org
Subject: Re: DTrace-like analysis possible with future Linux kernels?
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From: Florian Weimer <fw@deneb.enyo.de>
Date: Fri, 20 Aug 2004 15:46:33 +0200
In-Reply-To: <1093008895.7824.11.camel@boxen> (Alexander Nyberg's message of
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* Alexander Nyberg:

>> Most other system resources can be tracked quite easily: disk space,
>> CPU time, committed address space, even network I/O (with tcpdump and
>> netstat -p).  But there's no such thing for disk I/O.
>
> Why can't this be done be looking at the major faults a process causes?

Because only paging results in major faults, normal I/O with
read()/write() (or the p*() variants) does not.

> One could quite easily hack up a tool to monitor I/O per process or
> does it need to be very more precise?

It would be nice to obtain file names, too.