Received: by 10.213.65.68 with SMTP id h4csp2900302imn; Mon, 9 Apr 2018 10:50:21 -0700 (PDT) X-Google-Smtp-Source: AIpwx48QHZSe3p3mgZ1wVy/Z/ll1D2yY/a75YTz1VL3Vm6Ago1ag/3SPf3Xg/M/mzqDfVHYzkPhO X-Received: by 10.98.174.5 with SMTP id q5mr29824687pff.155.1523296221223; Mon, 09 Apr 2018 10:50:21 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1523296221; cv=none; d=google.com; s=arc-20160816; b=Akzg/18hP7CKxs0qQm1FA3RKo28/4ugXW5P6wLpAHgvZRK4mQdDuE9CpCayqTNhE/J i9sUuHd1j8XPYfPQZSBM4zA2dt3rnfU5nm6rJmjQxdhJWeE4tmg+wibGZY04uxFeXPxt X6CTPexO2DOhUkzMuQRHKbMCKLPjRSkowSf6ZaDmRYtq/Iun9vVMkHk8+tChW1T+nSMT J5igZBxjDhbvOvOEKNqGIEn/Ezo32xhXkokJTkqL+N5/t08Plge5RQiuLCWn/ijz1ELO IsX6x/opvR6f8IMUZCiOCg3iKLJW8eo+4FA4nVgnK7wvSJNH7tZVIlbYNPqv3Zn4S0OB YQlQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:mime-version:user-agent:message-id :in-reply-to:date:mail-followup-to:references:subject:cc:to:from :arc-authentication-results; bh=CKdiw2UED7vZupa86JmBLUIipUcFaZ3lXQCQCiAeWE4=; b=GA9tMGODqudC7qsFES2Z0kOOkuN0+xjae4qR0B0yvLmM+tUO0pey8xkzJW7CMOHSAk r7FzKM3zqciKIr22+7w5y0wDOqIdeno3w1qQwvX7VptObPFHWHVw0Y6u73vN+t9yTcWU x8ljHUMV36lwOUQrztC1uyGToAncJY85iQEqrZanrIqwnxGj0Icc+tdupkk4hf1rGb2Z RBFVvTNPuZzBTu5coZb3tNwZgenov8eibr6hVYFisZuHHD/NlcPrErHi0vwKX2x0Iw5t zXQmGM6vleQhHPHIWbr/Bzi8Wi9OlozmAGJiBFyEbm2a9fG9/+HrQa5ubzqt2jhoPZCc NJsA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id l137si482569pga.465.2018.04.09.10.49.42; Mon, 09 Apr 2018 10:50:21 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753352AbeDIRpw (ORCPT + 99 others); Mon, 9 Apr 2018 13:45:52 -0400 Received: from listserv2.niif.hu ([193.225.14.155]:33459 "EHLO listserv2.niif.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662AbeDIRpv (ORCPT ); Mon, 9 Apr 2018 13:45:51 -0400 Received: from business-188-142-225-206.business.broadband.hu ([188.142.225.206] helo=lant.ki.iif.hu) by listserv2.niif.hu with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1f5arV-0000E6-GF; Mon, 09 Apr 2018 19:45:49 +0200 Received: from wferi by lant.ki.iif.hu with local (Exim 4.89) (envelope-from ) id 1f5arP-0002Yq-W6; Mon, 09 Apr 2018 19:45:44 +0200 From: wferi@niif.hu (Ferenc =?utf-8?Q?W=C3=A1gner?=) To: linux-kernel@vger.kernel.org Cc: wferi@niif.hu Subject: Re: What's the priority of the idle task? References: <20180404143735.GA23925@aton> Mail-Followup-To: Ferenc =?utf-8?Q?W=C3=A1gner?= , linux-kernel@vger.kernel.org Date: Mon, 09 Apr 2018 19:45:43 +0200 In-Reply-To: <20180404143735.GA23925@aton> (Till Smejkal's message of "Wed, 4 Apr 2018 16:37:35 +0200") Message-ID: <876050ff3s.fsf@lant.ki.iif.hu> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Till Smejkal writes: > [...] Hence, the idle task is not managed by CFS and accordingly > doesn't have any nice value or priority (or at least it is not > important nowadays). Thanks for your very to-the-point answer! I'm still disturbed by the above statement, though, because not being managed by CFS does not imply having no meaningful priority: RT tasks seem to have one. Did you mean to imply this? Guessing not, I added your answer with code illustrations as https://unix.stackexchange.com/a/436575/119808. -- Regards, Feri