From owner-freebsd-current Thu Mar 23 15:29:13 2000 Delivered-To: freebsd-current@freebsd.org Received: from yana.lemis.com (yana.lemis.com [192.109.197.140]) by hub.freebsd.org (Postfix) with ESMTP id 365B237C54B for ; Thu, 23 Mar 2000 15:29:08 -0800 (PST) (envelope-from grog@mojave.worldwide.lemis.com) Received: from mojave.worldwide.lemis.com ([216.88.157.130]) by yana.lemis.com (8.8.8/8.8.8) with ESMTP id JAA02333; Fri, 24 Mar 2000 09:58:33 +1030 (CST) (envelope-from grog@mojave.worldwide.lemis.com) Received: (from grog@localhost) by mojave.worldwide.lemis.com (8.9.3/8.9.3) id PAA09554; Thu, 23 Mar 2000 15:28:10 -0800 (PST) (envelope-from grog) Date: Thu, 23 Mar 2000 15:28:10 -0800 From: Greg Lehey To: Poul-Henning Kamp Cc: Alfred Perlstein , Matthew Dillon , current@FreeBSD.ORG Subject: Re: patches for test / review Message-ID: <20000323152810.D9318@mojave.worldwide.lemis.com> Reply-To: Greg Lehey References: <20000320115902.C14789@fw.wintelcom.net> <21213.953589179@critter.freebsd.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <21213.953589179@critter.freebsd.dk>; from phk@critter.freebsd.dk on Mon, Mar 20, 2000 at 10:52:59PM +0100 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Monday, 20 March 2000 at 22:52:59 +0100, Poul-Henning Kamp wrote: > In message <20000320115902.C14789@fw.wintelcom.net>, Alfred Perlstein writes: >> * Poul-Henning Kamp [000320 11:45] 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 ? >> >> Yes it is really benificial. >> >> I'm not talking about a redesign of the clustering code as much as >> making the drivers that take a callback from it actually traverse >> the 'union cluster_info' rather than relying on the system to fake >> the pages being contiguous via remapping. >> >> There's nothing wrong with the clustering algorithms, it's just the >> steps it has to take to work with the drivers. > > Hmm, try to keep vinum/RAID5 in the picture when you look at this > code, it complicated matters a lot. I don't think it's that relevant, in fact. Greg -- Finger grog@lemis.com for PGP public key See complete headers for address and phone numbers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message