From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail06.adl2.internode.on.net ([150.101.137.129]:51573 "EHLO ipmail06.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751030AbdJOWWF (ORCPT ); Sun, 15 Oct 2017 18:22:05 -0400 Date: Mon, 16 Oct 2017 09:22:02 +1100 From: Dave Chinner Subject: Re: [PATCH V2] xfs: implement cgroup writeback support Message-ID: <20171015222202.GH3666@dastard> References: <20171015050751.dfznko2hxhi6jvra@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171015050751.dfznko2hxhi6jvra@kernel.org> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Shaohua Li Cc: linux-xfs@vger.kernel.org, darrick.wong@oracle.com, tj@kernel.org, Kernel-team@fb.com On Sat, Oct 14, 2017 at 10:07:51PM -0700, Shaohua Li wrote: > From: Shaohua Li > > Basically this is a copy of commit 001e4a8775f6(ext4: implement cgroup > writeback support). Tested with a fio test, verified writeback is > throttled against cgroup io.max write bandwidth, also verified moving > the fio test to another cgroup and the writeback is throttled against > new cgroup setting. > > I created a test for this as attached, please try! I'll send the test out for > inclusion later. Hmmm. The test you appended just checks that bytes get written. That's pretty much useless for verification of the features you describe above (throttling rate it correct, dynamic throttle application as memcg config changes). You explicitly state this is a memcg IO QoS feature and that you have a set of fio tests that verify that it works as expected. We need those "works as expected" fio tests formalised into automated fstests. Both upstream fs developers and downstream distro QE departments need to be able to verify that the bandwidth control and throttling works as advertised - it's essential that we have regression tests for this.... Cheers, Dave. -- Dave Chinner david@fromorbit.com