Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758483Ab1CaPuY (ORCPT ); Thu, 31 Mar 2011 11:50:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:6932 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758059Ab1CaPuW (ORCPT ); Thu, 31 Mar 2011 11:50:22 -0400 Date: Thu, 31 Mar 2011 11:49:42 -0400 From: Dave Jones To: Linus Torvalds Cc: Andrew Morton , Linux Kernel , Tejun Heo Subject: Re: excessive kworker activity when idle. (was Re: vma corruption in today's -git) Message-ID: <20110331154941.GA32045@redhat.com> Mail-Followup-To: Dave Jones , Linus Torvalds , Andrew Morton , Linux Kernel , Tejun Heo References: <20110329040939.GA32764@redhat.com> <20110331030917.GB26057@redhat.com> <20110331035511.GA1255@redhat.com> <20110331145850.GA10163@redhat.com> <20110331150344.GB10163@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1134 Lines: 27 On Thu, Mar 31, 2011 at 08:25:36AM -0700, Linus Torvalds wrote: > On Thu, Mar 31, 2011 at 8:03 AM, Dave Jones wrote: > > On Thu, Mar 31, 2011 at 10:58:50AM -0400, Dave Jones wrote: > > > > bah I missed a level. which seems to be the smoking gun. > > something in the tty layer seems to have gone nuts. > > Ahhah. That is indeed the smoking gun. > > I bet it's an old problem where something causes some stupid tty > ping-pong behaviour, and now it has become a high-CPU thing triggered > by commit f23eb2b2b285 ("tty: stop using "delayed_work" in the tty > layer"). > > Before that commit, if the tty layer got somehow confused, it would > always delay for a timer tick in between doing nothing. Now it will go > pretty much full blast. Which explains your CPU being hot. That's a recent change though, and I first saw this back in November. Dave -- 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/