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 74F7BEB64D8 for ; Wed, 14 Jun 2023 18:27:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233996AbjFNS14 (ORCPT ); Wed, 14 Jun 2023 14:27:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229832AbjFNS1x (ORCPT ); Wed, 14 Jun 2023 14:27:53 -0400 Received: from mail-lj1-x234.google.com (mail-lj1-x234.google.com [IPv6:2a00:1450:4864:20::234]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 00BFE2120 for ; Wed, 14 Jun 2023 11:27:51 -0700 (PDT) Received: by mail-lj1-x234.google.com with SMTP id 38308e7fff4ca-2b4274f7640so1057551fa.0 for ; Wed, 14 Jun 2023 11:27:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; t=1686767270; x=1689359270; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=ABp1fdnv+GxTRjoai1QiZdJs+Tqn9QPie2PZlQX7SYQ=; b=aUuV4t9Cp4YartQWekEqJSlGz4ilrPruLsK0cwj2wsptDwvKYbbUJ1Jdgsr8PdLywz K0M6WxGd8dFb1JcSTc3n4H0R3DpqvLwsjl/hpMvLcfavWazNyoTE95tMXpEaPHbOSRmU BAwtf6QmjcIlqogrk3Gg9S51FK+GfF5zT1AYU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686767270; x=1689359270; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=ABp1fdnv+GxTRjoai1QiZdJs+Tqn9QPie2PZlQX7SYQ=; b=CDPTZd8WgQFWSlLumSA//xbxHDKl1O0hrBlzZIFv6KR1pmwz1DGIKvK4MZAxrNaR4b 1yLSwiI4WcnPnYyE7fcr/BxVxBrOqY+ZpY6sJCwTaYGhxVwA2y4FN2MhB89ZVTlX3Zgt 9Kx2X0gj5gcayqWq2DIjKRp4vua+Rcv7YHvjsWcJ2UN2FV6tS+u8lSQwLgZil0OnjjI/ fefEAvdgszLEfZUCueboyRUzvp9BOy2mTC7cO2Kj62NrQ0sOrfpTpPhIe1mc7mslVp25 O3xpgUBso+RZkYPNLznVT5sQNnJz5MRkRRwepsOqeIByHzo5FE/uaNQ4A82Xx1kIkA57 vgfw== X-Gm-Message-State: AC+VfDxW6J0t6rlsfkozrkvSElQKhgGb30c98NbNnXrW1qxNUI84FBvj lGqnRmnqUCHKXT4h/jmOsTfasBc7JPWG5/kZ4bFpbA== X-Google-Smtp-Source: ACHHUZ5TwhhohYKXUJ45UiHCzDXDmdjiwBtYB9veq7wpGPUMmbcrFqDtvWXqSEGET17zCBQpTabvrm4ZHeFGXM5qMaw= X-Received: by 2002:a2e:8e28:0:b0:2b1:b06f:889d with SMTP id r8-20020a2e8e28000000b002b1b06f889dmr916884ljk.17.1686767270184; Wed, 14 Jun 2023 11:27:50 -0700 (PDT) MIME-Version: 1.0 References: <841849b5-1f9c-4f0e-2de8-1da278256888@kernel.org> <4849295d-9aef-836f-0e5f-063e2075380a@kernel.org> In-Reply-To: From: Joel Fernandes Date: Wed, 14 Jun 2023 14:27:38 -0400 Message-ID: Subject: Re: [RFC PATCH V3 6/6] sched/fair: Implement starvation monitor To: Juri Lelli Cc: Daniel Bristot de Oliveira , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , linux-kernel@vger.kernel.org, Luca Abeni , Tommaso Cucinotta , Thomas Gleixner , Vineeth Pillai , Shuah Khan Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 14, 2023 at 10:15=E2=80=AFAM Juri Lelli = wrote: > > Hey, [..] > > By postponing the enqueue/replanishment of the DL server here, we are f= ixing the > > problem in a practical way, that works without breaking existing useful= properties & > > use-cases. > > In my understanding, if we simply postpone actual activation of the DL > server up to the point it really needs to boost/run for giving CFS tasks > some breath (the infamous 0-laxity :), we save RT tasks from useless > interruptions and still can keep EDF/CBS working w/o much changes. > > It looks like a low hanging fruit, small improvement on what we have toda= y > than doesn't prevent us for implementing more complex features (i.e., ful= l > blown hierarchical scheduling, alternative schedulers) in the future if > the need arises. Agreed, thanks! - Joel