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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 3EAA4ECE58E for ; Tue, 15 Oct 2019 08:48:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0FA8621835 for ; Tue, 15 Oct 2019 08:48:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="hdwt12/0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729413AbfJOIso (ORCPT ); Tue, 15 Oct 2019 04:48:44 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:55452 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727735AbfJOIso (ORCPT ); Tue, 15 Oct 2019 04:48:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=PZs2Jew1Apcdf2AL00ZC9tQ/+7iCmPCjp3H58ifi9kY=; b=hdwt12/0qG3iaS8UDIeaV6OeT tFWgC5uur0rZhU5DuiIm1RCpWVqBjORlw4dLTzGtKm3n9dWhM48M9oQtbksvQoPa3gihlBl3dnsG8 BR8lVZ3SpR4xBhp/F+x+EAxPEnenm89BkltBeLWzPnbL+FtgOKCj5AOgn5ZEVQYCAWFy9y69O58Vk EMLzBLvIq7hS5X3kLFKcFqJF6u4JJMdj/W/++YE51InAPEdltcgY5S9qYGquoGugiYDNEVk3iVEuE K1GXMLtYoJluJU8UhTQcUwLGQMtOSmfqOTYUAc+7bgm5hM4/6BHQXpQ5la89gYMfjmNCSuRlV6t3/ SfMUNJt3w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iKIVP-0003za-My; Tue, 15 Oct 2019 08:48:35 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id CE17A304637; Tue, 15 Oct 2019 10:47:38 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 36F94284DE590; Tue, 15 Oct 2019 10:48:33 +0200 (CEST) Date: Tue, 15 Oct 2019 10:48:33 +0200 From: Peter Zijlstra To: Srinivas Pandruvada Cc: tony.luck@intel.com, bp@alien8.de, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, bberg@redhat.com, x86@kernel.org, linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org, hdegoede@redhat.com, ckellner@redhat.com Subject: Re: [PATCH 1/2] x86, mce, therm_throt: Optimize logging of thermal throttle messages Message-ID: <20191015084833.GD2311@hirez.programming.kicks-ass.net> References: <2c2b65c23be3064504566c5f621c1f37bf7e7326.camel@redhat.com> <20191014212101.25719-1-srinivas.pandruvada@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191014212101.25719-1-srinivas.pandruvada@linux.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org On Mon, Oct 14, 2019 at 02:21:00PM -0700, Srinivas Pandruvada wrote: > Some modern systems have very tight thermal tolerances. Because of this > they may cross thermal thresholds when running normal workloads (even > during boot). The CPU hardware will react by limiting power/frequency > and using duty cycles to bring the temperature back into normal range. > > Thus users may see a "critical" message about the "temperature above > threshold" which is soon followed by "temperature/speed normal". These > messages are rate limited, but still may repeat every few minutes. > > The solution here is to set a timeout when the temperature first exceeds > the threshold. Why can we even reach critical thresholds when the fans are working? I always thought it was BAD to ever reach the critical temps and have the hardware throttle.