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,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 9A3B2C433DB for ; Mon, 25 Jan 2021 01:22:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6ABBE2087D for ; Mon, 25 Jan 2021 01:22:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726625AbhAYBVd (ORCPT ); Sun, 24 Jan 2021 20:21:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45152 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726434AbhAYBUy (ORCPT ); Sun, 24 Jan 2021 20:20:54 -0500 Received: from mail-pl1-x633.google.com (mail-pl1-x633.google.com [IPv6:2607:f8b0:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7CB94C061573 for ; Sun, 24 Jan 2021 17:20:14 -0800 (PST) Received: by mail-pl1-x633.google.com with SMTP id b17so56911plz.6 for ; Sun, 24 Jan 2021 17:20:14 -0800 (PST) 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=rDCH8ssNvRh56D4K9BgC9iGmoQjBN/dPHMN5SJwmyYM=; b=AmEGBigeVqRqfuQsYXNce465V0cqwySPRdMKlDNNWGXL/qFq28BBfpOWJu7OoH31UI cvThXAc4uNYMfQ2fbmg931kPRmk67kpjeNnsj6m6dVleaPyszad48wnAUVsZl8V1CmRh t9Q4Tf+cnrGF4OmQ+bx8r5PdSNjKk3eVfu8jGXFq4Jco6wwNPzMz94hwhiTHrDVAnfPt 8WevLcjjPtUHDFxcMK/cjeV1z3tDDUDikAvftyrTPCG9CHoFEruRzPLaaq4lzrSrsgNA w0K+ccAJ64KMCOXuCUP0wvAwtEylZ/fypl5Iv6D+w3s2S7kLAUNkSHTyHP+PQt7vuOj+ GW1Q== 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=rDCH8ssNvRh56D4K9BgC9iGmoQjBN/dPHMN5SJwmyYM=; b=neeBly06V/+3EHGWRJtktr4pszDhyrOmh80Ghv2YKKf7+chnjRtyvQQMA6Yn0Gnyi8 qUCuYQyHEoLZyHUaEg+Li5gR2TV7ZCWUASYbcI20Q1m/YSFz9a+iFrd0K8aS7SVFSPKU EQrTiXfBYeHGdJ8CwtNaobfXftGgwVLxkgqe7oK9vFAVt0D+Jrqp9DQJWMhw/BtFWZKC xa76hI1TT86JTFFWN2Vy05FP+wtYVDONo7vevNfPZMhVKpjxy/VtWQn5GNuILoPNIo+c OQ8Rzxiig53XwtMRUrOva67lxi5I3s0Zn84PlPIH26BS64vniqwfH982AcNty0wc6V6D nzvA== X-Gm-Message-State: AOAM5324/H7sHC++x9JFbuoS4+ybNNVVfQtw24YahAVESTkYRq4UQyT7 0ekAuJtQRQSleIAMrcz/PNL9Hw== X-Google-Smtp-Source: ABdhPJzqbYXgncDR2lnPCLJ+J0lzKzqnrGnBt5/XyieRAjPImZgsybsBWCQnwUTLGTVyJHow5krSmw== X-Received: by 2002:a17:902:a512:b029:db:cf4c:336b with SMTP id s18-20020a170902a512b02900dbcf4c336bmr9248141plq.17.1611537613966; Sun, 24 Jan 2021 17:20:13 -0800 (PST) Received: from [192.168.4.41] (cpe-72-132-29-68.dc.res.rr.com. [72.132.29.68]) by smtp.gmail.com with ESMTPSA id i132sm7875777pfe.10.2021.01.24.17.20.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 24 Jan 2021 17:20:13 -0800 (PST) Subject: Re: [PATCH 0/2 v3] blk-mq: Improve performance of non-mq IO schedulers with multiple HW queues To: Jan Kara Cc: linux-block@vger.kernel.org, Ming Lei References: <20210111164717.21937-1-jack@suse.cz> From: Jens Axboe Message-ID: <7afa35b2-cf35-a149-d325-3ad2ae8d8935@kernel.dk> Date: Sun, 24 Jan 2021 18:20:11 -0700 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: <20210111164717.21937-1-jack@suse.cz> 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 1/11/21 9:47 AM, Jan Kara wrote: > Hello! > > This patch series aims to fix a regression we've noticed on our test grid when > support for multiple HW queues in megaraid_sas driver was added during the 5.10 > cycle (103fbf8e4020 scsi: megaraid_sas: Added support for shared host tagset > for cpuhotplug). The commit was reverted in the end for other reasons but I > believe the fundamental problem still exists for any other similar setup. The > problem manifests when the storage card supports multiple hardware queues > however storage behind it is slow (single rotating disk in our case) and so > using IO scheduler such as BFQ is desirable. See the second patch for details. Applied, thanks. -- Jens Axboe