Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 4 Mar 2003 08:21:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 4 Mar 2003 08:21:42 -0500 Received: from 205-158-62-139.outblaze.com ([205.158.62.139]:60557 "HELO spf1.us.outblaze.com") by vger.kernel.org with SMTP id ; Tue, 4 Mar 2003 08:21:41 -0500 Message-ID: <20030304133201.18619.qmail@mail.com> Content-Type: text/plain; charset="iso-8859-1" Content-Disposition: inline Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-Mailer: MIME-tools 5.41 (Entity 5.404) From: "David Anderson" To: linux-scsi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Date: Tue, 04 Mar 2003 08:32:01 -0500 Subject: I/O Request [Elevator; Clustering; Scatter-Gather] X-Originating-Ip: 133.145.164.4 X-Originating-Server: ws1-4.us4.outblaze.com Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1148 Lines: 25 Hi, I have been going through some documentation that talks of clustering, scatter-gather and elevator being used to improve performance. I am confused between these : This is what I have understood : Elevator The job of the elevator is to sort I/O requests to disk drives in such a way that the disk head moving in the same direction for maximum performance. Have been able to locate the code for the same. Clustering Combines multiple requests to adjecent blocks into a single request. Have not been able to find the code which carries this out. Any clue on where this is done in the linux source code ?? Do Clustering of request and scatter-gather mean the same ?? Confused to the core... Kindly help me ... Thanks and Regards, David Anderson -- __________________________________________________________ Sign-up for your own FREE Personalized E-mail at Mail.com http://www.mail.com/?sr=signup - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/