From owner-freebsd-current Mon Mar 20 23:52:10 2000 Delivered-To: freebsd-current@freebsd.org Received: from uni4nn.gn.iaf.nl (osmium.gn.iaf.nl [193.67.144.12]) by hub.freebsd.org (Postfix) with ESMTP id 1E0F037B5C1 for ; Mon, 20 Mar 2000 23:52:02 -0800 (PST) (envelope-from wilko@yedi.iaf.nl) Received: from yedi.iaf.nl (uucp@localhost) by uni4nn.gn.iaf.nl (8.9.2/8.9.2) with UUCP id IAA29845; Tue, 21 Mar 2000 08:26:05 +0100 (MET) Received: (from wilko@localhost) by yedi.iaf.nl (8.9.3/8.9.3) id AAA21609; Tue, 21 Mar 2000 00:04:37 +0100 (CET) (envelope-from wilko) Date: Tue, 21 Mar 2000 00:04:37 +0100 From: Wilko Bulte To: Poul-Henning Kamp Cc: Alfred Perlstein , Matthew Dillon , current@FreeBSD.ORG Subject: Re: patches for test / review Message-ID: <20000321000435.A8143@yedi.iaf.nl> Reply-To: wilko@FreeBSD.ORG References: <20000320111544.A14789@fw.wintelcom.net> <20102.953580112@critter.freebsd.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: <20102.953580112@critter.freebsd.dk>; from phk@critter.freebsd.dk on Mon, Mar 20, 2000 at 08:21:52PM +0100 X-OS: FreeBSD 3.4-STABLE X-PGP: finger wilko@freebsd.org Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Mon, Mar 20, 2000 at 08:21:52PM +0100, Poul-Henning Kamp wrote: > In message <20000320111544.A14789@fw.wintelcom.net>, Alfred Perlstein writes: > > >Keeping the currect cluster code is a bad idea, if the drivers were > >taught how to traverse the linked list in the buf struct rather > >than just notice "a big buffer" we could avoid a lot of page > >twiddling and also allow for massive IO clustering ( > 64k ) > > Before we redesign the clustering, I would like to know if we > actually have any recent benchmarks which prove that clustering > is overall beneficial ? > > I would think that track-caches and intelligent drives would gain > much if not more of what clustering was designed to do gain. Hm. But I'd think that even with modern drives a smaller number of bigger I/Os is preferable over lots of very small I/Os. Or have I missed the point? -- Wilko Bulte Arnhem, The Netherlands http://www.tcja.nl The FreeBSD Project: http://www.freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message