From owner-freebsd-net Fri Oct 26 2:53:40 2001 Delivered-To: freebsd-net@freebsd.org Received: from salmon.maths.tcd.ie (salmon.maths.tcd.ie [134.226.81.11]) by hub.freebsd.org (Postfix) with SMTP id 911B737B405 for ; Fri, 26 Oct 2001 02:53:38 -0700 (PDT) Received: from walton.maths.tcd.ie by salmon.maths.tcd.ie with SMTP id ; 26 Oct 2001 10:53:37 +0100 (BST) Date: Fri, 26 Oct 2001 10:53:34 +0100 From: David Malone To: Alfred Perlstein Cc: Luigi Rizzo , net@FreeBSD.ORG Subject: Re: performance issues with M_PREPEND on clusters Message-ID: <20011026105334.A14635@walton.maths.tcd.ie> References: <20011023110307.A34494@iguana.aciri.org> <20011023132813.I15052@elvis.mu.org> <20011023114650.C34494@iguana.aciri.org> <20011023140034.M15052@elvis.mu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20011023140034.M15052@elvis.mu.org>; from bright@mu.org on Tue, Oct 23, 2001 at 02:00:34PM -0500 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Tue, Oct 23, 2001 at 02:00:34PM -0500, Alfred Perlstein wrote: > Yes, you're right, I was mistaken in my paranioa, however you're > missing the fact that one may want to allocate an EXT buf and still > have it writeable. This is the function of M_RDONLY and M_WRITABLE framework which we put in place in -current about a year ago. I think we set things up so that sendfilebufs are not writable and so that custom external storage for jumbo ethernet frames are writeable. The changes were a bit big to port back to -stable. They involved moving external storage reference counts into the generic mbuf system. David. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message