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From: David Miller <davem@davemloft.net>
Subject: Re: TCP not triggering a fast retransmit?
Date: Wed, 30 Jun 2010 14:22:56 -0700 (PDT)
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From: Ben Hutchings <bhutchings@solarflare.com>
Date: Wed, 30 Jun 2010 22:03:49 +0100

> In that packet capture I see TCP payload lengths which are 2, 3 and 4
> times the usual MSS of 1448 bytes, which implies that GRO or LRO is in
> use.  In RHEL 5.4 the TCP stack does not ACK often enough in this case
> because it is missing this change:
> 
> commit ff9b5e0f08cb650d113eef0c654f931c0a7ae730
> Author: Herbert Xu <herbert@gondor.apana.org.au>
> Date:   Thu Aug 31 15:11:02 2006 -0700
> 
>     [TCP]: Fix rcv mss estimate for LRO

It certainly could be, I'll try make sure this gets rectified,
thanks!