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From: David Miller <davem@davemloft.net>
Subject: Re: [RFC v2: Patch 1/3] net: hand off skb list to other cpu to
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Date: Fri, 13 Mar 2009 19:19:51 -0700 (PDT)
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From: Tom Herbert <therbert@google.com>
Date: Fri, 13 Mar 2009 17:24:10 -0700

> Enabling HW multi-queue has somewhat higher CPU
> utilization though, the extra device interrupt load is not coming for
> free.  We actually use the HW multi-queue in conjunction with our
> software steering to get maximum pps (about 20% more).

This is a non-intuitive observation.  Using HW multiqueue should be
cheaper than doing it in software, right?