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 6694BC433EF for ; Wed, 5 Jan 2022 01:56:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236996AbiAEB4a (ORCPT ); Tue, 4 Jan 2022 20:56:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42144 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235779AbiAEB4a (ORCPT ); Tue, 4 Jan 2022 20:56:30 -0500 Received: from mail-yb1-xb34.google.com (mail-yb1-xb34.google.com [IPv6:2607:f8b0:4864:20::b34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E61B5C061761 for ; Tue, 4 Jan 2022 17:56:29 -0800 (PST) Received: by mail-yb1-xb34.google.com with SMTP id d1so92892624ybh.6 for ; Tue, 04 Jan 2022 17:56:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=0CTVeYrQLBXeJ/hr42oXjaVY0bTM3pTmbjTFyrIN+Ak=; b=L4dSmP+6ZIcA9YIZU7wA2OZv4nKsXSNDegbwC3TP96NqD4wLog/I9lh536xv8f4R1T ZGfQ+OEuzFVdyuHykEA8pK03gThdkwMi+A8ljsuphf885vZlufbWP8gJRQRPqtQy5Wmm B+K7De1uB0JO2dOS2dbKqcGyU2IpZaN+kw+/xQ1Cj0FpsuAp4E/io8IQuqn6LY6w8aX0 zl+/l6Yf8W+If5Vs++PgVM79Kvl7UveVh9au2PL+1oW777ZwLGH3C3t1VKCtA8tXG0Iy btpCdoVIP33Q1UTjkyUrMUmQRwRecANvxT2HvOgayPMbMnVstXUsOeFzJUVZgCTcY86f cgNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=0CTVeYrQLBXeJ/hr42oXjaVY0bTM3pTmbjTFyrIN+Ak=; b=MG7E99K0KaNksywLJ1uZwiSkUNMEjv6CT3KX0bEQwVyRMDZTsMzhdGGk7x/j8Tvop7 fp/mWDdyJa3d757aYkOsHe8QRJoQ1vIrmLSfvcCUgPBYRpklF25ZQ8at7420L5nSQq5N pBnKWlZotPk+6mIZGf/emQ2oNM5aqQRqGIrmrl1XKdVUswxjS/PhMR1a37zCcxM+a7h7 lWRHEM64bgI5LfojPKvVGZlvxVQHmHtbiu4rE9mZavCqultLKDXOKhTf62tzyC97UuKJ bDH7dDk7vBLBngpUL4DysA9YIdYmUMYT+ERI+hPSvCxSnTS5WoD7+iPtFowQzH3hK00x 5cbw== X-Gm-Message-State: AOAM5324+m+D/0sdRBrdG/zJhNqU4/r/5WR0oHyZ4XyHD7MiYEOs7Jcy Ph/v1o1RRPmcewShUB1ytkryBkw6+Bqvg86iGMEF7Q== X-Google-Smtp-Source: ABdhPJyqK9Y064QOcSOsyqxmGjHOY5Q4tuqwnvimGxYpa4VGPw9P+C5c6ZVFcER5owC4sX5pscFH4WeNNpDiZxALItk= X-Received: by 2002:a25:2e0a:: with SMTP id u10mr42539402ybu.246.1641347788872; Tue, 04 Jan 2022 17:56:28 -0800 (PST) MIME-Version: 1.0 References: <1640262603-19339-1-git-send-email-CruzZhao@linux.alibaba.com> <1640262603-19339-3-git-send-email-CruzZhao@linux.alibaba.com> In-Reply-To: <1640262603-19339-3-git-send-email-CruzZhao@linux.alibaba.com> From: Josh Don Date: Tue, 4 Jan 2022 17:56:17 -0800 Message-ID: Subject: Re: [PATCH 2/2] sched/core: Uncookied force idle accounting per cpu To: Cruz Zhao Cc: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Benjamin Segall , Mel Gorman , Daniel Bristot de Oliveira , Alexey Dobriyan , Eric Dumazet , linux-kernel , linux-fsdevel Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hi Cruz, On Thu, Dec 23, 2021 at 4:30 AM Cruz Zhao wrote: > > Forced idle can be divided into two types, forced idle with cookie'd task > running on it SMT sibling, and forced idle with uncookie'd task running > on it SMT sibling, which should be accounting to measure the cost of > enabling core scheduling too. > > This patch accounts the forced idle time with uncookie'd task, and the > sum of both. > > A few details: > - Uncookied forceidle time and total forceidle time is displayed via > the last two columns of /proc/stat. > - Uncookied forceidle time is ony accounted when this cpu is forced > idle and a sibling hyperthread is running with an uncookie'd task. What is the purpose/use-case to account the forced idle from uncookie'd tasks? The forced-idle from cookie'd tasks represents capacity loss due to adding in some cookie'd tasks. If forced idle is high, that can be rectified by making some changes to the cookie'd tasks (ie. their affinity, cpu budget, etc.).