Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754195Ab0GNJ5m (ORCPT ); Wed, 14 Jul 2010 05:57:42 -0400 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:47320 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752895Ab0GNJ5l (ORCPT ); Wed, 14 Jul 2010 05:57:41 -0400 From: Catalin Marinas To: Zeno Davatz Cc: linux-kernel@vger.kernel.org Subject: Re: kmemleak, cpu usage jump out of nowhere References: Date: Wed, 14 Jul 2010 10:57:33 +0100 In-Reply-To: (Zeno Davatz's message of "Wed, 14 Jul 2010 08:12:48 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-OriginalArrivalTime: 14 Jul 2010 09:57:37.0397 (UTC) FILETIME=[FD3E1250:01CB233A] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1505 Lines: 36 Zeno Davatz wrote: > I got a new Intel core-8 i7 processor. > > I am on kernel uname -a > > Linux zenogentoo 2.6.35-rc5 #97 SMP Tue Jul 13 16:13:25 CEST 2010 i686 > Intel(R) Core(TM) i7 CPU 960 @ 3.20GHz GenuineIntel GNU/Linux > > Sometimes in the middle of nowhere all of a sudden all of my 8-cores > are at 100% CPU usage and my machine really lags and hangs and is not > useable anymore. Some random process just grabs a bunch CPUs according > to htop. > > dmesg tell me that > > kmemleak: 38 new suspected memory leaks (see /sys/kernel/debug/kmemleak) > kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak) > kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) > kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak) > kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak) > kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) These may be related to the NO_BOOTMEM configuration (I sent a patch in a separate reply). But even when kmemleak scans the memory, it only uses a single thread and you should only see a single CPU going to 100%. I don't think kmemleak scanning can explain why all the 8 cores are going up to 100%. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/