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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B0AEC10F14 for ; Thu, 10 Oct 2019 17:28:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0724620659 for ; Thu, 10 Oct 2019 17:28:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726291AbfJJR2j (ORCPT ); Thu, 10 Oct 2019 13:28:39 -0400 Received: from foss.arm.com ([217.140.110.172]:36680 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725862AbfJJR2i (ORCPT ); Thu, 10 Oct 2019 13:28:38 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AA45628; Thu, 10 Oct 2019 10:28:37 -0700 (PDT) Received: from [10.1.194.37] (e113632-lin.cambridge.arm.com [10.1.194.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 545A83F71A; Thu, 10 Oct 2019 10:28:37 -0700 (PDT) Subject: Re: Question about sched_prio_to_weight values To: Francesco Poli , linux-kernel@vger.kernel.org References: <20191007003205.8888ac99da2dd732b6198387@paranoici.org> <506d5ee6-246a-a03d-ea11-227ff4de1467@arm.com> <20191007224143.d21abae57a3f32ac60afd53c@paranoici.org> From: Valentin Schneider Message-ID: <21c11aca-e531-7d72-9a70-f52c12d5d408@arm.com> Date: Thu, 10 Oct 2019 18:28:36 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20191007224143.d21abae57a3f32ac60afd53c@paranoici.org> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/10/2019 21:41, Francesco Poli wrote: > The differences are probably due to the different precision > of the computations: I don't know the precision of those originally > carried out by Ingo Molnar (single precision? double?), but calc(1) > is an arbitrary precision calculator and, by default, performs > calculations with epsilon = 1e-20 ! > > Please note that, except for the first one, all the differing > values obtained with the calc(1) script have slightly better > errors than the ones found in kernel/sched/core.c ... > As always patches are welcome, but I don't know how much there is to gain from a tiny error correction in those factors. Out of curiosity, what led you to stare at those numbers? > > Thanks again for the clarification! > Bye. >