Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161859Ab3DEORl (ORCPT ); Fri, 5 Apr 2013 10:17:41 -0400 Received: from cantor2.suse.de ([195.135.220.15]:33305 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161777Ab3DEORk (ORCPT ); Fri, 5 Apr 2013 10:17:40 -0400 Date: Fri, 5 Apr 2013 16:17:38 +0200 From: Jan Kara To: Raymond Jennings Cc: Linux Kernel Mailing List Subject: Re: block device queues, elevatoring implicit or explicit? Message-ID: <20130405141738.GB21852@quack.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 788 Lines: 20 On Sat 16-03-13 02:06:00, Raymond Jennings wrote: > Are all block devices fundamentally elevators or fifos or what? > > To be blunt, if a bunch of concurrent processes dump requests on a > noop queue, are they serviced fifo or in elevator order or what? > > My goal is to get a dumb elevator that does nothing but sweep up and > down the disk mopping up outstanding requests as the disk heads ooze > across the sectors. With noop io scheduler you get the FIFO ordering of requests. Honza -- Jan Kara SUSE Labs, CR -- 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/