From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f196.google.com ([209.85.161.196]:34177 "EHLO mail-yw0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751515AbcK1WIV (ORCPT ); Mon, 28 Nov 2016 17:08:21 -0500 Date: Mon, 28 Nov 2016 17:08:18 -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 11/15] blk-throttle: add interface to configure think time threshold Message-ID: <20161128220818.GA12948@htj.duckdns.org> References: <52aae27038728bf0fd1b2b3b6536fcc28c9f2e6c.1479161136.git.shli@fb.com> <20161123213243.GD11306@mtj.duckdns.org> <20161124010629.GB4724@ksenks-mbp.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20161124010629.GB4724@ksenks-mbp.dhcp.thefacebook.com> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org Hello, Shaohua. On Wed, Nov 23, 2016 at 05:06:30PM -0800, Shaohua Li wrote: > > Shouldn't this be a per-cgroup setting along with latency target? > > These two are the parameters which define how the cgroup should be > > treated time-wise. > > It should be easy to make it per-cgroup. Just not sure if it should be > per-cgroup. The logic is if the disk is faster, wait time should be shorter to > not harm performance. So it sounds like a per-disk characteristic. Yes, this is something dependent on the device, but also on the workload. For both this parameter and the latency target, it seems that they should be specified along with the actual device limits so that they follow the same convention and can be specified per cgroup * block device. What do you think? Thanks. -- tejun