From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v2 net-next] tcp: avoid expensive pskb_expand_head()
 calls
Date: Thu, 19 Apr 2012 19:25:06 +0200
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To: Rick Jones <rick.jones2@hp.com>
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On Thu, 2012-04-19 at 10:20 -0700, Rick Jones wrote:

> By copying them to smaller buffers? Or just by altering truesize? 
> Wasn't the whole point of fixing all the broken truesize settings to 
> accurately account for memory consumed?

I checked, their truesize are OK (1024+256) for ixgbe driver.
They could be little smaller, but not that much. (512 + 256)

No, its only the sk_rcvbuf is small for a tcp sender,
and sk_add_backlog() makes sure we dont queue more than sk_rcvbuf bytes
in backlog.