Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752424AbcCKLtk (ORCPT ); Fri, 11 Mar 2016 06:49:40 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:60119 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751455AbcCKLtb (ORCPT ); Fri, 11 Mar 2016 06:49:31 -0500 Date: Fri, 11 Mar 2016 03:49:27 -0800 From: Christoph Hellwig To: Nikolay Borisov Cc: Christoph Hellwig , Linus Walleij , Ulf Hansson , Tejun Heo , Paolo Valente , Jens Axboe , Fabio Checconi , Arianna Avanzini , linux-block@vger.kernel.org, "linux-kernel@vger.kernel.org" , Mark Brown Subject: Re: [PATCH RFC 09/22] block, cfq: replace CFQ with the BFQ-v0 I/O scheduler Message-ID: <20160311114927.GA28637@infradead.org> References: <20160211222210.GC3741@mtj.duckdns.org> <8FDE2B10-9BD2-4741-917F-5A37A74E5B58@linaro.org> <20160217170206.GU3741@mtj.duckdns.org> <72E81252-203C-4EB7-8459-B9B7060029C6@linaro.org> <20160301184656.GI3965@htj.duckdns.org> <20160304173947.GA16764@infradead.org> <20160311111714.GC3450@infradead.org> <56E2AAE8.8000203@kyup.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <56E2AAE8.8000203@kyup.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 550 Lines: 10 On Fri, Mar 11, 2016 at 01:24:24PM +0200, Nikolay Borisov wrote: > Out of curiosity - would it make sense to have something like BFQ/CFQ > for single-queue blk-mq users? The mess that CFQ is certainly not. But we want to eventually be able to get rid of the legacy request code, so we need suitable I/O scheduling. See the threads at: https://lkml.org/lkml/2015/11/19/227 or http://thread.gmane.org/gmane.linux.scsi/111257/focus=111320 for more details. A leightweight bfq-like scheduler might come in handy on top of Andreas' time slicing work.