From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <erdnetdev@gmail.com>
Subject: Re: [PATCH] xen/netfront: improve truesize tracking
Date: Wed, 19 Dec 2012 08:17:49 -0800
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Cc: Ian Campbell <Ian.Campbell@citrix.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	annie li <annie.li@oracle.com>,
	"xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
To: Sander Eikelenboom <linux@eikelenboom.it>
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On Wed, 2012-12-19 at 12:34 +0100, Sander Eikelenboom wrote:

> Hi Ian,
> 
> It ran overnight and i haven't seen the warn_once trigger.
> (but i also didn't with the previous patch)
> 

As I said, the miminum value to not trigger the warning was what Ian
patch was doing, but it was still a not accurate estimation.

Doing the real accounting might trigger slow transferts, or dropped
packets because of socket limits (SNDBUF / RCVBUF) being hit sooner.

So the real question was : If accounting for full pages, is your
applications run as smooth as before, with no huge performance
regression ?