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From: David Miller <davem@davemloft.net>
Subject: Re: TSO not 10G friendly if peer is close enough
Date: Tue, 17 Apr 2012 17:47:59 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 17 Apr 2012 23:38:42 +0200

> Hmm... maybe tcp_trim_head should not trim but only update an offset in
> skb... With some luck, offset can reach skb->len when all data is
> ACKnowledged...

This is definitely the way to fix this.  Just essentially defer all
the page operations until later when the entire SKB is consumed.