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Date: Wed, 02 Mar 2011 16:25:04 -0800
From: Bart Kus <me@bartk.us>
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Subject: Re: [linux-lvm] Tracing IO requests?
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To: LVM general discussion and development <linux-lvm@redhat.com>

On 3/2/2011 3:44 PM, Ray Morris wrote:
>>> On 3/2/2011 12:13 PM, Jonathan Tripathy wrote:
>>> I know the IO is only being caused by a "cp -a" command, but the
>>> issue is why all the reads?  It should be 99% writes.
> cp has to read something before it can write it elsewhere.

Ray, my bad, I should have specified, the cp reads from a different 
volume/set of drives.

Thanks for the systemtap tip, Dave!

--Bart