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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 71D47C76192 for ; Tue, 16 Jul 2019 14:11:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 484B320693 for ; Tue, 16 Jul 2019 14:11:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="IQjAYIFl" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728384AbfGPOL5 (ORCPT ); Tue, 16 Jul 2019 10:11:57 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:34583 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726039AbfGPOLx (ORCPT ); Tue, 16 Jul 2019 10:11:53 -0400 Received: by mail-pf1-f195.google.com with SMTP id b13so9187651pfo.1 for ; Tue, 16 Jul 2019 07:11:53 -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=7plrCe7cNTS0+Z/xokDsw3l+fNtSeqJL0Jrh4WZePeU=; b=IQjAYIFlhWgS2pmAEDWTEk6uDc/BgtT1FAtmk9N5fRCu1YTn8bGTXAeI7TXX+SW7gs Fvm3uTrVcyNHEBvYpeUWzmPV+fpDZmlqnkNLAMFrQDC4VpEfSkuAv6iyBcm6baW3N66O mcRWK9r/mHsg54EOgJIf7ACPPGIX+g9aoo2NFadFdxquBggUSFe7ZRUtqhDsGUs6PAF5 CGbdNCLmirCF4r+w/AXsswWE9fXsuIx3piexaXKy7Qw6hu3xv1RzPtOF2OxicW3LJOON UQm2SSAPGgNN+dKOqpl5ry/6RiUrqu/YhelSbUrql9zR2W+iFxrd+4kBLmcpteFTfAS6 pncw== 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=7plrCe7cNTS0+Z/xokDsw3l+fNtSeqJL0Jrh4WZePeU=; b=Np/JyYQ9jawmodDaYIn4a1J04Y3KDogxjAYSGfxr2Ltff6oWlcFBOHrToOlL33C73d +f+l7kUxFD2/ZqTaIYxtljr+WcPWiLYiZ+rt7KxGbXHLKFRObVPAKUIQuMxVwxyhYUu/ ofAM3wbgDyLZS0ncvJ+ZHP497t2GjZvccIijoYsgAEcyRRNPWjAZ35XMBbRKJxws6N0W IeCaXc+d/pekqrf6kFHolq+BYZKV3Z84aTMYDz6o/jnPp5+Sh1O0G3XInKvAJX6FEyzB ur/6EsKn8Pp8E47W+epR899XWWFubz7c49+UYyzRNNdW8XQKRdja+j6KfWnUZv0jCtD5 OLiA== X-Gm-Message-State: APjAAAUGea7NF6miBMbSiGIa4Ggr8yZCboGCgVC3oJhT3EVRxfB/TAwa KqeJu6itWFyHjdVDDegoHTA= X-Google-Smtp-Source: APXvYqxWonvROtYZuFnyeiQD93daARvUGt8q3WqJQ8VqbqRis3eCqaIjCof04P1rEfOgx0NZ/bVz3w== X-Received: by 2002:a63:2f44:: with SMTP id v65mr33469693pgv.185.1563286312858; Tue, 16 Jul 2019 07:11:52 -0700 (PDT) Received: from [192.168.1.121] (66.29.164.166.static.utbb.net. [66.29.164.166]) by smtp.gmail.com with ESMTPSA id t7sm10699361pfh.101.2019.07.16.07.11.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Jul 2019 07:11:51 -0700 (PDT) Subject: Re: [PATCH BUGFIX IMPROVEMENT V2 0/1] block, bfq: eliminate latency regression with fast drives To: Paolo Valente Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, ulf.hansson@linaro.org, linus.walleij@linaro.org, bfq-iosched@googlegroups.com, oleksandr@natalenko.name References: <20190715105719.20353-1-paolo.valente@linaro.org> From: Jens Axboe Message-ID: <6867cf11-d7f8-cadf-b9ec-85549bb86af3@kernel.dk> Date: Tue, 16 Jul 2019 08:11:49 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190715105719.20353-1-paolo.valente@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 7/15/19 4:57 AM, Paolo Valente wrote: > [V2 that should apply cleanly on current HEAD] > > Hi Jens, > I've spotted a regression on a fast SSD: a loss of I/O-latency control > with interactive tasks (such as the application start up I usually > test). Details in the commit. > > I do hope that, after proper review, this commit makes it for 5.3. If it's a regression, it should have a Fixes: line telling us which commit originally introduced the regression. This is important for folks doing backports. Can you add that? -- Jens Axboe