From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755330AbaDWRRc (ORCPT ); Wed, 23 Apr 2014 13:17:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45830 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751188AbaDWRRa (ORCPT ); Wed, 23 Apr 2014 13:17:30 -0400 Date: Wed, 23 Apr 2014 13:17:20 -0400 From: Vivek Goyal To: Tejun Heo Cc: Jens Axboe , linux-kernel@vger.kernel.org, Li Zefan , cgroups@vger.kernel.org Subject: Re: [PATCH RFC] blkcg: prepare blkcg knobs for default hierarchy Message-ID: <20140423171720.GF24651@redhat.com> References: <20140413013209.GC26252@mtj.dyndns.org> <20140414180824.GB9552@redhat.com> <20140414193214.GC16835@htj.dyndns.org> <20140415135359.GA13033@redhat.com> <20140415140650.GI1863@htj.dyndns.org> <20140415141826.GB17018@redhat.com> <20140423170141.GJ4781@htj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140423170141.GJ4781@htj.dyndns.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 23, 2014 at 01:01:41PM -0400, Tejun Heo wrote: > On Tue, Apr 15, 2014 at 10:18:26AM -0400, Vivek Goyal wrote: > > Ok, that's fine. Let us just document the knobs well so that people can > > find which knob is giving what information and make cfq names better at > > the expense of inconsistency of names with throttling layer. > > I've been thinking about it more. Why do we even have separate stats > for common things like bytes transferred? It doesn't serve any > purpose to do double accounting and reporting on everything, does it? > Shouldn't we just have single set of common stats for things like > requests / bytes serviced? I think we should just require two. One for measuring rate in terms of IOPS and other for measuring rate in terms of [kMG]B/sec. So exporting both sector and bytes seems redundant. May be exporting bytes and dropping sector interface will do. Is size of sector exported somewhere so that user space can easily convert bytes to sector if needed. Number of bio/requests also will need to be exported so that one can come up with IOPS. Thanks Vivek