From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261221AbVFDCJW (ORCPT ); Fri, 3 Jun 2005 22:09:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261222AbVFDCJW (ORCPT ); Fri, 3 Jun 2005 22:09:22 -0400 Received: from smtp202.mail.sc5.yahoo.com ([216.136.129.92]:57466 "HELO smtp202.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S261221AbVFDCJR (ORCPT ); Fri, 3 Jun 2005 22:09:17 -0400 Message-ID: <42A10D47.2030209@yahoo.com.au> Date: Sat, 04 Jun 2005 12:09:11 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.6) Gecko/20050324 Debian/1.7.6-1 X-Accept-Language: en MIME-Version: 1.0 To: Jack Steiner CC: linux-kernel@vger.kernel.org Subject: Re: Hang in sched_balance_self() References: <20050603225544.GA8499@sgi.com> In-Reply-To: <20050603225544.GA8499@sgi.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jack Steiner wrote: > Nick - > > The latest 2.6.12-rc5-mm2 tree fails to boot on some of the 64p > SGI systems. The system hangs immediately after printing: > > ... > Inode-cache hash table entries: 8388608 (order: 12, 67108864 bytes) > Mount-cache hash table entries: 1024 > Boot processor id 0x0/0x0 > Brought up 64 CPUs > Total of 64 processors activated (118415.36 BogoMIPS). > > > I have isolated the failure to cpu 0 hanging in sched_balance_self() during > a fork (or clone). The "while" loop at the end of function never > terminates, ie. sd is never NULL. > > Is this a problem that you have seen before. If not, I'll do some > more digging & isolate the problem. > Hi Jack, I have not seen this problem, however I don't think it has had much testing with multilevel NUMA domains. If you could do some more digging that would be great, however I plan to get time on a 64-way IA64 next week and look at some scheduler issues, so I'll keep this in mind if you haven't made any progress. Thanks, Nick -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com