From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Marcotte Subject: Re: NUMA problem with AMD G34 system Date: Mon, 21 Feb 2011 08:20:02 -0500 Message-ID: <20110221132002.GA13858@panix.com> References: <20110219085932.E08B624258@panix5.panix.com> <4D6226F0.1080007@amd.com> <20110221112958.GA25000@panix.com> <4D6251C8.1020809@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4D6251C8.1020809@amd.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Andre Przywara Cc: Brian Marcotte , "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org > I prepared Xen to handle this situation (nodes without memory) > before the M-C launch, before that it simply crashed. I agree that > it is not obvious that you need to populate at least 4 DIMMs per > CPU. I suppose that Xen could arrange the cpu to node mapping such that the memoryless CPUs were assigned to the "nearest" node making it so you could benefit from the shared L3 cache. I don't know that it's worth anyone's time though. Perhaps a warning would suffice? > Do you have only 4 DIMMs? Yes, but I don't expect that to last too long. We find that over the lifetime of a machine, we max out the RAM slots long before we run out of CPU. The second CPU is mostly just so we can (eventually) fill all the RAM slots. It's not a problem to run with one CPU for while. I may also just pin the domains to particular CPU cores rather than pull the CPU. Thanks for your help. -- - Brian