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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 19531C388F9 for ; Tue, 27 Oct 2020 10:32:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A208B20790 for ; Tue, 27 Oct 2020 10:32:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="TCt+Vxjp"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="CVyx/4nx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2898298AbgJ0Kam (ORCPT ); Tue, 27 Oct 2020 06:30:42 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:46160 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2898094AbgJ0K2y (ORCPT ); Tue, 27 Oct 2020 06:28:54 -0400 Date: Tue, 27 Oct 2020 11:28:51 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1603794532; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VQ7zMCv9WzoVlZNW1UUVkVwr9kP9FCotl44bX4Fv43o=; b=TCt+Vxjp1CP4YSakfOfvQNtZYZkWm4SVMqLUFFADYjdOxreUiMIFn/lvosfkn2m39bsnqR sU/GjKDC/+Gasbs/+BWAHCPSeY/UNMseV8URz/k6UoQ/u/30GBZGIAFXYL7YNXxkBa+k8u d+cbly04RM2D/HQFiYkn85hKfdEaNx5EePLEDaF9OUSAKeYjSzYPfNvahCCcDpaq55WTmI yRAyGDQnUxVlmEbIgHGlr60IsqlpNxYV7/AlhIMZoc/X9CXZ62DtoYQfRuHdt+yRGxon4Y VNEUL+hPmyZflfvSZkn5N4bSSVMBXMkOxGF01MN7jqhevodR4ERY/+ewZ6KEZQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1603794532; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VQ7zMCv9WzoVlZNW1UUVkVwr9kP9FCotl44bX4Fv43o=; b=CVyx/4nxryfOPhCo3hrrE3MO+VXGIy8ucvbHmsEKj9qDhv48nfEuJeRDEoY7M10El6CszO mt6WtszF9+Us/sBQ== From: Sebastian Andrzej Siewior To: Daniel Wagner Cc: Thomas Gleixner , LKML , linux-rt-users , Steven Rostedt Subject: Re: [ANNOUNCE] v5.9.1-rt19 Message-ID: <20201027102851.gizepjlu4opensqb@linutronix.de> References: <20201024091838.gzhn2dlx2j7xnixg@linutronix.de> <20201027093616.5vn6xinmthxulhvx@beryllium.lan> <20201027100049.xtkmjqdwkn7zec2f@linutronix.de> <20201027102547.y6wop7j2ovzg2tyx@beryllium.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20201027102547.y6wop7j2ovzg2tyx@beryllium.lan> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-10-27 11:25:47 [+0100], Daniel Wagner wrote: > Well, one thing I need to figure out is how to get pi_stress working > correctly on my machines (that is for all -rt trees, so it's nothing > new). It consistently triggers RCU stall warnings with hackbench as > workload. Clark told me the test only works if there are enough CPUs to > run on. Need to look into it. Is it running as a RT task? Do you have RCU-boosting enabled? Otherwise it looks that if you throw enough non-RT load on the system, RCU can not catch up which does not sound good. Sebastian