From owner-freebsd-net  Thu Jul 11 14:15:36 2002
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Date: Thu, 11 Jul 2002 17:15:10 -0400
From: Bosko Milekic <bmilekic@unixdaemons.com>
To: Juan Francisco Rodriguez Hervella <jrh@lab.it.uc3m.es>
Cc: freebsd-net@FreeBSD.ORG
Subject: Re: mbuf external buffer reference counters
Message-ID: <20020711171510.A19053@unixdaemons.com>
References: <20020711133802.A31827@iguana.icir.org> <Pine.LNX.3.96.1020711225805.22207A-100000@lm011.lab.it.uc3m.es>
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In-Reply-To: <Pine.LNX.3.96.1020711225805.22207A-100000@lm011.lab.it.uc3m.es>; from jrh@lab.it.uc3m.es on Thu, Jul 11, 2002 at 11:00:56PM +0200
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On Thu, Jul 11, 2002 at 11:00:56PM +0200, Juan Francisco Rodriguez Hervella wrote:
> First of all, let me say that Im newbie with these topics, 
> I only know a bit about mbufs, but I dont understand how
> can an application trim away the refcount if the size is
> MCLBYTES = 2040 - sizeof(refcount).
> 
> Don't this limit the room which an app. can write ?

 No.  It just changes it.  Also, it's not the application trimming away
 anything, and the size is not 2040, it's 2048. :-)

 FWIW, the application has no idea about mbufs or clusters.  These are
 buffers and structures only the kernel knows about.

> Thanks.
> 
> JFRH

-- 
Bosko Milekic
bmilekic@unixdaemons.com
bmilekic@FreeBSD.org


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