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 02D7AC636D4 for ; Mon, 30 Jan 2023 19:13:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238248AbjA3TN2 (ORCPT ); Mon, 30 Jan 2023 14:13:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44784 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238325AbjA3TN1 (ORCPT ); Mon, 30 Jan 2023 14:13:27 -0500 Received: from mail-pj1-f44.google.com (mail-pj1-f44.google.com [209.85.216.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A25B044A9; Mon, 30 Jan 2023 11:13:26 -0800 (PST) Received: by mail-pj1-f44.google.com with SMTP id j5so12008419pjn.5; Mon, 30 Jan 2023 11:13:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Ye2d44HpWhl3SswDOdkTRrNgF3Mq2fxwH8BmkcnO8nw=; b=XqnReN1WcfwuPnJSBGfWmZvN2zHIZglyd+K1/EgR3RaMLdZNeOreKtOkZOUc9AaHk3 Ytqp0azQmXkGcni2AW77gXy603BVsZF9yw0pV7Qm6sS5INmXg6H99odqez9ps0a/2Bo8 rrZnS0FE1yKWEEKqGV1GZ5p0OAdMN8orASEGo7c2p4hSsGjSEuRncHAFmmYSRiQjDEso usEeuDf/Ng2I3PniSFkgXhYVwc+MRHN+vKmOwAgCL1gor4il2y4o4XSKo5EjeGCtHTc/ Jxs+VdznBep+H5XafKP/cGpIYlLWIokjXJcD1OjKFtUYUjAN22/hTSVcifvj7BTtmFaA sdMQ== X-Gm-Message-State: AFqh2kpnCLJh5ZF9CTwZF50fGbpYkI0DF3vXOQGcxMDDMxyUcZMkfJtH FeaJMTjNgIOIyJy8tIO6HzAgqlhgrxA= X-Google-Smtp-Source: AMrXdXvDPY0evIWZsB+g2b5E/H59SVv6fGjhNwzRtSh07DLkQ/fJCbG1etSA15svNsARCK2F5VKZBQ== X-Received: by 2002:a17:90b:1b45:b0:22b:b6d5:e347 with SMTP id nv5-20020a17090b1b4500b0022bb6d5e347mr39008967pjb.29.1675106005582; Mon, 30 Jan 2023 11:13:25 -0800 (PST) Received: from ?IPV6:2620:15c:211:201:5016:3bcd:59fe:334b? ([2620:15c:211:201:5016:3bcd:59fe:334b]) by smtp.gmail.com with ESMTPSA id mv12-20020a17090b198c00b0021952b5e9bcsm9676883pjb.53.2023.01.30.11.13.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 30 Jan 2023 11:13:24 -0800 (PST) Message-ID: <9547f182-4ec2-021c-5860-5cc2e3dc515a@acm.org> Date: Mon, 30 Jan 2023 11:13:22 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.0 Subject: Re: [PATCH v3 01/18] block: introduce duration-limits priority class Content-Language: en-US To: "Martin K. Petersen" , Damien Le Moal Cc: Niklas Cassel , Paolo Valente , Jens Axboe , Christoph Hellwig , Hannes Reinecke , "linux-scsi@vger.kernel.org" , "linux-ide@vger.kernel.org" , "linux-block@vger.kernel.org" References: <20230124190308.127318-2-niklas.cassel@wdc.com> <731aeacc-74c0-396b-efa0-f9ae950566d8@opensource.wdc.com> <873e0213-94b5-0d81-a8aa-4671241e198c@acm.org> <4c345d8b-7efa-85c9-fe1c-1124ea5d9de6@opensource.wdc.com> <5066441f-e265-ed64-fa39-f77a931ab998@acm.org> <275993f1-f9e8-e7a8-e901-2f7d3a6bb501@opensource.wdc.com> <86de1e78-0ff2-be70-f592-673bce76e5ac@opensource.wdc.com> <7f0a2464-673a-f64a-4ebb-e599c3123a24@acm.org> <29b50dbd-76e9-cdce-4227-a22223850c9a@opensource.wdc.com> <049a7e88-89d1-804f-a0b5-9e5d93d505f7@opensource.wdc.com> <4e803108-9526-6a75-f209-789a06ef52f9@opensource.wdc.com> From: Bart Van Assche In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 1/28/23 12:25, Martin K. Petersen wrote: > - Wrt. ioprio as conduit, I personally really dislike the idea of > conflating priority (relative performance wrt. other I/O) with CDL > (which is a QoS concept). I would really prefer those things to be > separate. However, I do think that the ioprio *interface* is a good > fit. A tool like ionice seems like a reasonable approach to letting > generic applications set their CDL. Hi Martin, My understanding is that ionice uses the ioprio_set() system call and hence only affects foreground I/O but not page cache writeback. This is why I introduced the ioprio rq-qos policy (block/blk-ioprio.c). How about not adding CDL support in ioprio_set() and only supporting configuration of CDL via the v2 cgroup mechanism? Thanks, Bart.