From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Latency difference between fifo and pfifo_fast
Date: Tue, 06 Dec 2011 07:02:57 +0100
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To: "John A. Sullivan III" <jsullivan@opensourcedevel.com>
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Le lundi 05 d=C3=A9cembre 2011 =C3=A0 23:10 -0500, John A. Sullivan III=
 a =C3=A9crit :
> Hello, all.  We are trying to minimize latency on our iSCSI SAN.  The
> network is entirely dedicated to the iSCSI traffic.  Since all the
> traffic is the same, would it make sense to change the qdisc for that
> interface to fifo from the default pfifo_fast or is the latency
> difference between the two completely negligible? Thanks - John

A very small difference indeed. How many packets per second are
expected ? What kind of NIC are you using ?