From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] net: netdev_alloc_skb() use build_skb()
Date: Tue, 05 Jun 2012 04:46:35 +0200
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Cc: Willy Tarreau <w@1wt.eu>, David Miller <davem@davemloft.net>,
	netdev@vger.kernel.org
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Tue, 2012-06-05 at 00:54 +0300, Michael S. Tsirkin wrote:

> Yes but what bugs me if the box is not under memory pressure
> this overestimation limits buffers for no real gain.
> How about we teach tcp to use data_len for buffer
> limits normally and switch to truesize when low on memory?
> 

You should first have evidence of the effect of this limitation.

I see more evidence of poor choices at driver level than core level.