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Date: Mon, 02 Jan 2012 20:29:27 -0500
From: "Dieter BSD" <dieterbsd@engineer.com>
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Subject: Re: cmp(1) has a bottleneck, but where?
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>> Task: cp(1) a several-GB file from one drive to another,
>> then run cmp(1) to verify.  Cp runs as expected, but
>> cmp runs slower than expected.  Neither the disks
>> nor the cpu is maxed out.  Local drives, no network
>> involved.  Machine is otherwise idle.
>
>    1. How are you running cmp?
>    2. Why do you claim cmp is the bottleneck? Is it spinning the CPU?

cmp big_file /other_disk/big_file

Cmp is running slower than it should.  It isn't cpu bound ( 67.5%Idle )
but it isn't disk bound either.  Seems like it should be one or the
other.