From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next-2.6] pktgen: adding prefetchw() call
Date: Fri, 10 Dec 2010 15:37:07 -0800 (PST)
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From: Junchang Wang <junchangwang@gmail.com>
Date: Thu, 9 Dec 2010 10:55:16 +0800

> We know for sure pktgen is going to write skb->data right after
> *_alloc_skb, causing unnecessary cache misses.
> 
> Idea is to add a prefetchw() call to prefetch the first cache line
> indicated by skb->data. On systems with Adjacent Cache Line Prefetch,
> it's probably two cache lines are prefetched.
> 
> With this patch, pktgen on Intel SR1625 server with two E5530 
> quad-core processors and a single ixgbe-based NIC went from 8.63Mpps
> to 9.03Mpps, with 4.6% improvement.
> 
> Signed-off-by: Junchang Wang <junchangwang@gmail.com>
> Acked-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied, thanks.