From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: TCPBacklogDrops during aggressive bursts of traffic
Date: Tue, 15 May 2012 18:34:01 +0200
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To: Kieran Mansley <kmansley@solarflare.com>
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On Tue, 2012-05-15 at 17:29 +0100, Kieran Mansley wrote:
> On Tue, 2012-05-15 at 16:56 +0200, Eric Dumazet wrote:
> > 
> > Please try latest kernels, this is probably 'fixed'
> 
> I've just tried with 3.4.0-rc7 and the problem is still reproducible.
> It's perhaps harder to reproduce than on 3.3.6 but still there.
> 
> > What network driver are you using ? 
> 
> The receiver is using the sfc driver that is included in the kernel
> build, together with an SFC 9020 NIC. 
> 
> Kieran
> 

MTU ?

What is typical skb->truesize of skb given to stack in RX path ?

If drivers use PAGE_SIZE fragments, then you are more likely to hit
limit.