From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761117AbXKAND6 (ORCPT ); Thu, 1 Nov 2007 09:03:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760726AbXKANDr (ORCPT ); Thu, 1 Nov 2007 09:03:47 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:36768 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1760693AbXKANDp (ORCPT ); Thu, 1 Nov 2007 09:03:45 -0400 Date: Thu, 1 Nov 2007 06:03:44 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: David Miller cc: akpm@linux-foundation.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, mathieu.desnoyers@polymtl.ca, penberg@cs.helsinki.fi Subject: Re: [patch 0/7] [RFC] SLUB: Improve allocpercpu to reduce per cpu access overhead In-Reply-To: <20071101.021451.217578606.davem@davemloft.net> Message-ID: References: <20071031.181335.207429553.davem@davemloft.net> <20071101.000118.208338243.davem@davemloft.net> <20071101.021451.217578606.davem@davemloft.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 1 Nov 2007, David Miller wrote: > > This hunk helped the sparc64 looping OOPS I was getting, but cpus hang > > in some other fashion soon afterwards. > > And if I bump PER_CPU_ALLOC_SIZE up to 128K it seems to mostly work. Good.... > You'll definitely need to make this work dynamically somehow. Obviously. Any ideas how? I can probably calculate the size based on the number of online nodes when the per cpu areas are setup. But the setup is done before we even parse command line arguments. That would still mean a fixed size after bootup. In order to make it truly dynamic we would have to virtually map the area. vmap? But that reduces performance.