Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756721AbcKVUQr (ORCPT ); Tue, 22 Nov 2016 15:16:47 -0500 Received: from mail-yw0-f194.google.com ([209.85.161.194]:34562 "EHLO mail-yw0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755837AbcKVUQp (ORCPT ); Tue, 22 Nov 2016 15:16:45 -0500 Date: Tue, 22 Nov 2016 15:16:43 -0500 From: Tejun Heo To: Shaohua Li Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Kernel-team@fb.com, axboe@fb.com, vgoyal@redhat.com Subject: Re: [PATCH V4 03/15] blk-throttle: configure bps/iops limit for cgroup in high limit Message-ID: <20161122201643.GB17534@htj.duckdns.org> References: <7a4f1b1b0f67bb02d0caadae808c1a89413c202d.1479161136.git.shli@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7a4f1b1b0f67bb02d0caadae808c1a89413c202d.1479161136.git.shli@fb.com> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 639 Lines: 16 On Mon, Nov 14, 2016 at 02:22:10PM -0800, Shaohua Li wrote: > each queue will have a state machine. Initially queue is in LIMIT_HIGH > state, which means all cgroups will be throttled according to their high > limit. After all cgroups with high limit cross the limit, the queue state > gets upgraded to LIMIT_MAX state. > cgroups without high limit will use max limit for their high limit. Haven't looked at the actual mechanism yet so please correct me if I'm getting it wrong but at least the above explanation reads incorrect. Shouldn't max limits applied regardless of whether other cgroups are above high or not? Thanks. -- tejun