Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264093AbTEaApe (ORCPT ); Fri, 30 May 2003 20:45:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264094AbTEaApe (ORCPT ); Fri, 30 May 2003 20:45:34 -0400 Received: from gateway-1237.mvista.com ([12.44.186.158]:18174 "EHLO hermes.mvista.com") by vger.kernel.org with ESMTP id S264093AbTEaApd (ORCPT ); Fri, 30 May 2003 20:45:33 -0400 Subject: Re: [PATCH][CFT] new IO scheduler for 2.4.20 From: Robert Love To: Neil Schemenauer Cc: Con Kolivas , linux-kernel@vger.kernel.org, akpm@digeo.com In-Reply-To: <20030531005247.GA646@glacier.arctrix.com> References: <20030530220923.GA404@glacier.arctrix.com> <200305310940.41780.kernel@kolivas.org> <20030531005247.GA646@glacier.arctrix.com> Content-Type: text/plain Message-Id: <1054317501.15356.2183.camel@localhost> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.3.92 (1.3.92-1) (Preview Release) Date: 30 May 2003 17:58:21 +0000 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2003-05-31 at 00:52, Neil Schemenauer wrote: > I didn't change the size of the request queue. I can't find where that > gets set in 2.4.20. :-( in drivers/block/ll_rw_blk.c :: blk_init_free_list() I think the main reason (aside from memory consumption) 2.4 has such small queues is to minimize read latency. If your patch goes off fixes that, you can probably get away with larger queues, which will help in merging. But then you definitely want to look into always merging reads, like Andrew does. A maximum of ~1000 request entries seems nice if you really give a boost to reads otherwise. Robert Love - 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/