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=-3.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 8AFF8C433DF for ; Wed, 5 Aug 2020 17:37:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6272122D6D for ; Wed, 5 Aug 2020 17:37:16 +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="SNRJxYhc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728895AbgHERhL (ORCPT ); Wed, 5 Aug 2020 13:37:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54390 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728893AbgHERfG (ORCPT ); Wed, 5 Aug 2020 13:35:06 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15536C001FC2 for ; Wed, 5 Aug 2020 08:31:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.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; bh=ihXFtoBSuvtLohh/RvNeAjifvCivLgmoMzFjTemcXXU=; b=SNRJxYhcymyueDueAlAmzlc+wu mTrx+TaefdMhYPmbw3mUXokg5Svh3p2wlp9zpr0FcUX0wH2Mz/TsKW/6dndyvKP+Eii5XHUMdnQr2 tDK7+CM8aOaxmoAdFcZ9UZKdsbeYM5uDJVfLQ4kxzYsUHYrkAUuXSK+fkrsIER12IM/0eIeprk76r mLjwDUZU6E7zGtmBtF5zfDvPJ815weh5P7ydY9i5qUPDbmrXWdDHadj1s7uB7KB6phhuuMZJ7Eal4 DzCgaE1nAqa3+pJ06Rhmh532fUOyRbKO4BADXpJacMZu2i+iapPcW6TV+GvKGkM2gBSWX2Gebh3TA 3WYhVMMQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1k3LO1-0001kt-22; Wed, 05 Aug 2020 15:31:25 +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 04026301A66; Wed, 5 Aug 2020 17:31:20 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B77A922B957E9; Wed, 5 Aug 2020 17:31:20 +0200 (CEST) Date: Wed, 5 Aug 2020 17:31:20 +0200 From: peterz@infradead.org To: Valentin Schneider Cc: Thomas Gleixner , Vladimir Oltean , Kurt Kanzenbach , Alison Wang , catalin.marinas@arm.com, will@kernel.org, paulmck@kernel.org, mw@semihalf.com, leoyang.li@nxp.com, vladimir.oltean@nxp.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Anna-Maria Gleixner Subject: Re: [RFC PATCH] arm64: defconfig: Disable fine-grained task level IRQ time accounting Message-ID: <20200805153120.GU2674@hirez.programming.kicks-ass.net> References: <87mu3ho48v.fsf@kurt> <20200730082228.r24zgdeiofvwxijm@skbuf> <873654m9zi.fsf@kurt> <87lfiwm2bj.fsf@nanos.tec.linutronix.de> <20200803114112.mrcuupz4ir5uqlp6@skbuf> <87d047n4oh.fsf@nanos.tec.linutronix.de> <875z9zmt4i.fsf@nanos.tec.linutronix.de> <20200805134002.GQ2674@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 05, 2020 at 02:56:49PM +0100, Valentin Schneider wrote: > I've been tempted to say the test case is a bit bogus, but am not familiar > enough with the RT throttling details to stand that ground. That said, from > both looking at the execution and the stress-ng source code, it seems to > unconditionally spawn 32 FIFO-50 tasks (there's even an option to make > these FIFO-99!!!), which is quite a crowd on monoCPU systems. Oh, so it's a case of: we do stupid without tuning and the system falls over. I can live with that.