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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,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 80227C432BE for ; Thu, 26 Aug 2021 23:51:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 58A4E60EBA for ; Thu, 26 Aug 2021 23:51:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231509AbhHZXwB (ORCPT ); Thu, 26 Aug 2021 19:52:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229710AbhHZXwB (ORCPT ); Thu, 26 Aug 2021 19:52:01 -0400 Received: from mail-io1-xd2e.google.com (mail-io1-xd2e.google.com [IPv6:2607:f8b0:4864:20::d2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40307C061757 for ; Thu, 26 Aug 2021 16:51:13 -0700 (PDT) Received: by mail-io1-xd2e.google.com with SMTP id y18so6167319ioc.1 for ; Thu, 26 Aug 2021 16:51:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=9lt+JYE+cgMyyJXz9REO9WWyxY4NGB0h/zyFB1xx8Sg=; b=Xp49W2e/mpqdfpR4X33JcNfhkF/bi0snMCZ6itiJ6Lw0+4/FBZOISKD03rbMMsH867 Mm8FMLFA112ctZkAz/7MnCzmP9wCCCJcEeXzOUpyFzmVq3QuLZRLGCOT5pKSki1fCnoS ceNSxsxvE0ByLg6r09eERmgzgn522/OE5AzttLRQxEu2MAIvck9bX5rVMraNezMaEtID /99kH0WmxOWnDTB9DTYnbhbAaEuhhgtR7iettt/HXKHo2SUn+4YAg7dlrImm/Mdym7Vs CjeAVwdzQwd7Tsgdd5oY5H+cGqyvVLXv4OjZJeaqQebAgIznNonUELIGDlGSxN4gnfdf HihQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=9lt+JYE+cgMyyJXz9REO9WWyxY4NGB0h/zyFB1xx8Sg=; b=QTkup4DOaHmRYjE5+ZEzhXzxRX4eQ8BHusvl1zr74QKQxWgXEXAMRWpNVL7F7EgLMr 35429be2mnvWGdZi+Qttc1Ri8tWcX1uyChRMxppkwbQoVOeGCN/eOg5ly5DGIwkDtl1j 3+kqAPYpd0G77N2FzjoEoGECLjirX7Mo+WlB+hucrvPxKV3VgOIFCP54UTDn5DlDImBS p0WMd50xH6sb1q21w4akN5SRREQ4hZ1ybn7LAREfFXkr36ml9eYXNUWJy59/Fe4ewnoJ Lbxcf7uEovDiqYeWnA+rcQ33Kw9onb50W7dHifAnEAYoJkJ/nlxMQjmRuAM0si9Q3fhf aiQQ== X-Gm-Message-State: AOAM532wEMOElBAN6gA3bysvD4RbulPnzsma9bq6eXYGE9aMvzPnmalQ XeZAFmLIzyn+JVLxd3IyovZL6g== X-Google-Smtp-Source: ABdhPJzl47AokWsNflYgoHOWZOc4vty0vWcGrp2KRzJv6IVcSQC6h2ZGhYJOL2s03692A2oHLHX/Qg== X-Received: by 2002:a6b:905:: with SMTP id t5mr4993149ioi.209.1630021872622; Thu, 26 Aug 2021 16:51:12 -0700 (PDT) Received: from [192.168.1.116] ([66.219.217.159]) by smtp.gmail.com with ESMTPSA id i14sm926141iol.27.2021.08.26.16.51.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 26 Aug 2021 16:51:12 -0700 (PDT) Subject: Re: [PATCH] block/mq-deadline: Speed up the dispatch of low-priority requests To: Bart Van Assche , Zhen Lei , linux-block Cc: Damien Le Moal References: <20210826144039.2143-1-thunder.leizhen@huawei.com> <537620de-646d-e78e-ccb8-4105bac398b3@kernel.dk> <82612be1-d61e-1ad5-8fb5-d592a5bc4789@kernel.dk> <59c19a63-f321-94e8-cb31-87e88bd4e3d5@acm.org> From: Jens Axboe Message-ID: <0ef7865d-a9ce-c5d9-ff7f-c0ef58de3d21@kernel.dk> Date: Thu, 26 Aug 2021 17:51:10 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <59c19a63-f321-94e8-cb31-87e88bd4e3d5@acm.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 8/26/21 5:49 PM, Bart Van Assche wrote: > On 8/26/21 11:45 AM, Jens Axboe wrote: >> Just ran a quick test here, and I go from 3.55M IOPS to 1.23M switching >> to deadline, of which 37% of the overhead is from dd_dispatch(). >> >> With the posted patch applied, it runs at 2.3M IOPS with mq-deadline, >> which is a lot better. This is on my 3970X test box, so 32 cores, 64 >> threads. > > Hi Jens, > > With the script below, queue depth >= 2 and an improved version of > Zhen's patch I see 970 K IOPS with the mq-deadline scheduler in an > 8 core VM (i7-4790 CPU). In other words, more IOPS than what Zhen > reported with fewer CPU cores. Is that good enough? That depends, what kind of IOPS are you getting if you revert the original change? -- Jens Axboe