From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] rps: introduce a new sysctl switch
 rps_workaround_buggy_driver
Date: Thu, 05 Apr 2012 13:07:07 +0200
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Cc: netdev@vger.kernel.org
To: Li Yu <raise.sail@gmail.com>
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On Thu, 2012-04-05 at 18:31 +0800, Li Yu wrote:
> We encountered a buggy NIC driver or hardware/firmware, it keeps
> non-zero constant skb->rxhash for long time, so if we enabled RPS,
> the targeted CPU keeps same for long time too.
> 
> This patch introduces a sysctl switch to workaround for such problem,
> if the switch was on, RPS core discards the skb->rxhash that is
> computed by NIC hardware.
> 
> Hope this patch also can help others, thanks.

Really ?

to disable this driver rxhash, you should try :

ethtool -K eth0 rxhash off