From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C261C433DB for ; Wed, 24 Feb 2021 09:31:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C0D8864EBB for ; Wed, 24 Feb 2021 09:31:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234349AbhBXJbk (ORCPT ); Wed, 24 Feb 2021 04:31:40 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:12995 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232166AbhBXJb3 (ORCPT ); Wed, 24 Feb 2021 04:31:29 -0500 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4DlrG55sl6zjRTj; Wed, 24 Feb 2021 17:29:01 +0800 (CST) Received: from [10.174.179.129] (10.174.179.129) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.498.0; Wed, 24 Feb 2021 17:30:31 +0800 Subject: Re: question about relative control for sync io using bfq To: Paolo Valente CC: Jens Axboe , Ming Lei , "Christoph Hellwig" , linux-block , chenzhou , "houtao (A)" References: <7E41BC22-33EA-4D0F-9EBD-3AB0824E3F2E@linaro.org> <7c28a80f-dea9-d701-0399-a22522c4509b@huawei.com> <554AE702-9A13-4FB5-9B29-9AF11F09CE5B@linaro.org> <97ce5ede-0f7e-ce63-7a92-01c3356f4e44@huawei.com> <3E4B9F62-7376-4CA5-9C9D-21F6B9437313@linaro.org> <6ba9537b-052c-715b-111b-34a7d53179ec@huawei.com> <9E3D68B7-35D3-412E-8196-BF5AACDB1377@linaro.org> From: "yukuai (C)" Message-ID: <591785c0-d762-8a96-8d54-d52b6ac3595e@huawei.com> Date: Wed, 24 Feb 2021 17:30:31 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <9E3D68B7-35D3-412E-8196-BF5AACDB1377@linaro.org> Content-Type: text/plain; charset="gbk"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.174.179.129] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 2021/02/23 18:52, Paolo Valente wrote: > In a sense, my solution is an evolution of your initial solution. It > is conceptually very simple: just track whether all weights and all > I/O sizes are equal. When this condition holds true, no idling is > needed. When it does not hold, idling is needed. Your case would be > solved, service guarantees would be always preserved. Hi, The solution sounds good, and it's ture that my case would be solved. Thank you very much! Yu Kuai