From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Date: Thu, 08 Dec 2005 23:40:58 +0000 Subject: Re: [discuss] Re: [PATCH 1/3] Zone reclaim V3: main patch Message-Id: <20051208234058.GA11190@wotan.suse.de> List-Id: References: <20051208203707.30456.57439.sendpatchset@schroedinger.engr.sgi.com> <20051208210850.GS11190@wotan.suse.de> <20051208225102.GW11190@wotan.suse.de> <20051208232827.GZ11190@wotan.suse.de> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Christoph Lameter Cc: Andi Kleen , akpm@osdl.org, Christoph Hellwig , linux-ia64@vger.kernel.org, steiner@sgi.com, linux-kernel@vger.kernel.org, Wu Fengguang , discuss@x86-64.org On Thu, Dec 08, 2005 at 03:35:05PM -0800, Christoph Lameter wrote: > On Fri, 9 Dec 2005, Andi Kleen wrote: > > > > My experience is that at 20 systems do not need zone reclaim yet. > > > > I really cannot confirm your experience here. > > Maybe the meaning of these numbers varies? I know that 10 is a local > access but the assumption in include/linux/numa.h that 20 is a remote > access is probably already a guess. The spec seems to suggest it's roughly the NUMA factor scaled (so for 1.4 you would get 14). But I haven't actually seen a Opteron with correct SLIT yet so I don't know what they use ... > I know that our Altix machines seem to use 10 for a local and 20 for > nonlocal but same box. The distances then increase from there. Unless non local same box is 2 times as slow as the local I wouldn't consider that correct. (I would expect the Altix to do better than that) -Andi