From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [NET][TG3] Fwd: page allocation failure with linux 3.1.1
Date: Mon, 28 Nov 2011 20:28:14 +0100
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To: Rick Jones <rick.jones2@hp.com>
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Le lundi 28 novembre 2011 =C3=A0 11:05 -0800, Rick Jones a =C3=A9crit :
> On 11/28/2011 12:26 AM, Eric Dumazet wrote:

> > Since some devices might copy skb to a linear one in their
> > ndo_start_xmit(), we could set a netdev limit so that TSO can still=
 be
> > used on these devices, but limiting number of frags to
> > 2^PAGE_ALLOC_COSTLY_ORDER
>=20
> How much "TSO value" remains after such a copy?

Instead of filling up to 64Kbytes + one head of data per skb, we'll fil=
l
32kbytes (8*4Kbytes) + one head.

Thats still better than 1460 bytes per skb :)