Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753494Ab3JWLzl (ORCPT ); Wed, 23 Oct 2013 07:55:41 -0400 Received: from mail-vb0-f67.google.com ([209.85.212.67]:57165 "EHLO mail-vb0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753172Ab3JWLzk (ORCPT ); Wed, 23 Oct 2013 07:55:40 -0400 MIME-Version: 1.0 Date: Wed, 23 Oct 2013 19:38:32 +0800 Message-ID: Subject: A thought about IO scheduler From: =?GB2312?B?uqvA2g==?= To: linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 879 Lines: 16 Nowadays,the IO schedulers in linux kernel have four types: deadline,noop,Anticiptory and CFQ.CFQ is the default scheduler.But CFQ is not a good scheduler for SSD,dealine may be a good choice. When deadline runs,it has a mount of computation about merging and sorting.Merge has three types: front_merge,no_merge and back_merge. Why don't have another type: merge based same sector.For example,it have two bios in a request list,theyboth have the same bi->sector,the bi->size maybe not equal. Whether can we put the latter bio replace the former?What do you find that significant?Or the other levels in OS has finished this function? -- 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/