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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67C48EB64D9 for ; Wed, 5 Jul 2023 03:18:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229793AbjGEDSA (ORCPT ); Tue, 4 Jul 2023 23:18:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35638 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229772AbjGEDR7 (ORCPT ); Tue, 4 Jul 2023 23:17:59 -0400 Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A9D61B6; Tue, 4 Jul 2023 20:17:58 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4QwlGN40wVz4f3mK4; Wed, 5 Jul 2023 11:17:48 +0800 (CST) Received: from [10.174.176.73] (unknown [10.174.176.73]) by APP4 (Coremail) with SMTP id gCh0CgAHvbDd4KRkFajwNA--.34759S3; Wed, 05 Jul 2023 11:17:50 +0800 (CST) Subject: Re: [PATCH RFC 0/7] blk-mq: improve tag fair sharing To: Bart Van Assche , Yu Kuai , axboe@kernel.dk Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, yi.zhang@huawei.com, yangerkun@huawei.com, Christoph Hellwig , "yukuai (C)" References: <20230618160738.54385-1-yukuai1@huaweicloud.com> <4c9fea33-9c30-4ab9-c210-95e09d323837@acm.org> <82d44ba1-4389-079c-935a-cbb49203ca27@huaweicloud.com> From: Yu Kuai Message-ID: <84f9bfb4-293b-ad55-97e4-e8c611c5e9ca@huaweicloud.com> Date: Wed, 5 Jul 2023 11:17:48 +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: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-CM-TRANSID: gCh0CgAHvbDd4KRkFajwNA--.34759S3 X-Coremail-Antispam: 1UD129KBjvJXoW7tF1kKF1ktFy5AF4kKr13CFg_yoW8Gw17pF WrKas0yw4ktry2kr92gw1DWF4ftrZ3Jr4UZr1rXwn7Awn8KFW2vFWrtas0kasrur4qgF4j 9F4vkrZYyF4kJaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkE14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvEwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lc7I2V7IY0VAS07AlzVAY IcxG8wCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14 v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkG c2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI 0_Jr0_Gr1lIxAIcVCF04k26cxKx2IYs7xG6rWUJVWrZr1UMIIF0xvEx4A2jsIE14v26r1j 6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUdHU DUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi, 在 2023/07/04 2:08, Bart Van Assche 写道: > On 7/3/23 06:29, Yu Kuai wrote: >> 在 2023/06/20 23:20, Bart Van Assche 写道: >>> On 6/18/23 09:07, Yu Kuai wrote: >>>> This is not a formal version and not fully tested, I send this RFC >>>> because I want to make sure if people think doing this is meaningful, >>>> before I spend too much time on this. >>> The approach looks good to me but I'd like to hear from Jens and >>> Christoph what their opinion is about the approach of this patch >>> series before doing an in-depth review. >>> >> Any suggestions on this topic? It'll be great to hear that if anyone >> thinks it's meaningful to refactor tag fair sharing. > > The cover letter of this patch series says "This is not a formal version > and not fully tested". If a fully tested version will be posted, I will > help with an in-depth review. Thanks for taking time on this patchset, do you think I need to do following for the formal version, or these improvements can be done later? - current algorithm to borrow tags in patch 7 is very easy and straightforward, it should work fine on simple caces like the case you reported for ufs, but this algorithm should be improved for more complicated cases. - currently borrowed tags will never be returned untill queue is idle, I should figure out a way to return borrowed tags if this queue is not busy, so that other queues can borrow tag from this queue. Thanks, Kuai > > Thanks, > > Bart. > > > . >