Received: by 2002:a05:6a10:5bc5:0:0:0:0 with SMTP id os5csp2016839pxb; Thu, 28 Oct 2021 14:37:26 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzAikaKgCaV5gvdgM2AoG95gfz5PIVKi4+/IX9/tGnHcf5Rclu5HWyr939unsLLOCVLQWhY X-Received: by 2002:a63:735e:: with SMTP id d30mr5249340pgn.448.1635457046610; Thu, 28 Oct 2021 14:37:26 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1635457046; cv=none; d=google.com; s=arc-20160816; b=odrirXM1NXnHU6YhiSXCGFJdohMFPtTeiw/0EYg3KxDdSeoyc6uRPUTnozNdWKcXMp lZpKRpNQR5VRQl9O/Dl5C7KFy2+P76p5sN0EFMt6P56J9mN8TxO7xJXg5nit7nPpVUxS PuLmHEug/5xaBv7k4c7IRjvlgXBiOSE470eJIX+AKId5QG4bZ2/fa8yEIiD3JiWbBaDm ACfLJ6Yes0obqNKWRacTkCsrWZLkVTmkfhZP2cSBklmKhasXfCByo7uflWCWC0Pig6LJ xj+8GaiVs7PMMtRxjhGX9mwDdjZv1Bsz05cSWFAKufDpffoGypr1MUMKjWEnMwpBtVfC m1ww== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:date:cc:to:from:subject :message-id; bh=4vkfwecjPow+KowqGN8PyQF8BH6G4TyoTIrcvnYXrx4=; b=qajW0oODx7sLLQxvWDkIbFjiFvc5Ll2ImqrQGbm/+fo3t3/oDJ+VNjmCiSE7hBOIyo rrzfkAgDTcysLkF8bKa13qyRjFdIEh6EE7b2OwPyxodun2pV0EzDViayyMg5sPH2DLfK IfMVp2vaO5cNn5A5OkVTHxgKXZowcuHD+bA3uqi1AH3WHTQV48/rTl7uUAUzY6w7vWnm PzFlPPVnhLv2mkbW7E+VdCue++JOMkQYUe4LXVQMzJxurgOdDSwmbCk9RGXaGZ2tPDMv Df/3/jSrNKKx94x+t78ovIAfjobrRC5JqFSBJJjoTJm3iYwIbirKdDsNk/23nxr1N04c /HBw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id lw2si6055818pjb.140.2021.10.28.14.37.14; Thu, 28 Oct 2021 14:37:26 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231325AbhJ1Vih (ORCPT + 99 others); Thu, 28 Oct 2021 17:38:37 -0400 Received: from mga02.intel.com ([134.134.136.20]:7162 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230522AbhJ1Vig (ORCPT ); Thu, 28 Oct 2021 17:38:36 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10151"; a="217704023" X-IronPort-AV: E=Sophos;i="5.87,191,1631602800"; d="scan'208";a="217704023" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Oct 2021 14:36:09 -0700 X-IronPort-AV: E=Sophos;i="5.87,191,1631602800"; d="scan'208";a="466289015" Received: from schen9-mobl.amr.corp.intel.com ([10.212.137.85]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Oct 2021 14:36:08 -0700 Message-ID: <8f6b4ab17a319117cbed8751aa4fa9f2d6e0ca5b.camel@linux.intel.com> Subject: Re: [PATCH v3 0/5] Improve newidle lb cost tracking and early abort From: Tim Chen To: Vincent Guittot Cc: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, linux-kernel@vger.kernel.org Date: Thu, 28 Oct 2021 14:36:08 -0700 In-Reply-To: <20211028121530.GA19512@vingu-book> References: <20211019123537.17146-1-vincent.guittot@linaro.org> <7128695d64e9161637b67315b5beb51c4accdc82.camel@linux.intel.com> <720fd26424927dd27fea4e5719dafe8a0afaa8c4.camel@linux.intel.com> <20211028121530.GA19512@vingu-book> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 (3.34.4-1.fc31) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2021-10-28 at 14:15 +0200, Vincent Guittot wrote: > > > It seems to make sense to skip the call > > to nohz_newidle_balance() for this case? > > nohz_newidle_balance() also tests this condition : > (this_rq->avg_idle < sysctl_sched_migration_cost) > and doesn't set NOHZ_NEWILB_KICKi in such case > > But this patch now used the condition : > this_rq->avg_idle < sd->max_newidle_lb_cost > and sd->max_newidle_lb_cost can be higher than > sysctl_sched_migration_cost > > which means that we can set NOHZ_NEWILB_KICK: > -although we decided to skip newidle loop > -or when we abort because this_rq->avg_idle < curr_cost + sd- > >max_newidle_lb_cost > > This is even more true when sysctl_sched_migration_cost is lowered > which is your case IIRC > > The patch below ensures that we don't set NOHZ_NEWILB_KICK in such > cases: > Thanks. Will ask our benchmark team to give it a spin. Tim