From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932090Ab0I3PR7 (ORCPT ); Thu, 30 Sep 2010 11:17:59 -0400 Received: from e38.co.us.ibm.com ([32.97.110.159]:41291 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756662Ab0I3PR6 (ORCPT ); Thu, 30 Sep 2010 11:17:58 -0400 Message-ID: <4CA4AA21.9030109@austin.ibm.com> Date: Thu, 30 Sep 2010 10:17:53 -0500 From: Nathan Fontenot User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.12) Gecko/20100915 Thunderbird/3.0.8 MIME-Version: 1.0 To: Robin Holt CC: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@ozlabs.org, Greg KH , Dave Hansen , KAMEZAWA Hiroyuki Subject: Re: [PATCH 0/8] v2 De-Couple sysfs memory directories from memory sections References: <4CA0EBEB.1030204@austin.ibm.com> <20100928123848.GH14068@sgi.com> <4CA2313D.2030508@austin.ibm.com> <20100929192830.GK14068@sgi.com> In-Reply-To: <20100929192830.GK14068@sgi.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/29/2010 02:28 PM, Robin Holt wrote: > On Tue, Sep 28, 2010 at 01:17:33PM -0500, Nathan Fontenot wrote: >> On 09/28/2010 07:38 AM, Robin Holt wrote: >>> I was tasked with looking at a slowdown in similar sized SGI machines >>> booting x86_64. Jack Steiner had already looked into the memory_dev_init. >>> I was looking at link_mem_sections(). >>> >>> I made a dramatic improvement on a 16TB machine in that function by >>> merely caching the most recent memory section and checking to see if >>> the next memory section happens to be the subsequent in the linked list >>> of kobjects. >>> >>> That simple cache reduced the time for link_mem_sections from 1 hour 27 >>> minutes down to 46 seconds. >> >> Nice! >> >>> >>> I would like to propose we implement something along those lines also, >>> but I am currently swamped. I can probably get you a patch tomorrow >>> afternoon that applies at the end of this set. >> >> Should this be done as a separate patch? This patch set concentrates on >> updates to the memory code with the node updates only being done due to the >> memory changes. >> >> I think its a good idea to do the caching and have no problem adding on to >> this patchset if no one else has any objections. > > I am sorry. I had meant to include you on the Cc: list. I just posted a > set of patches (3 small patches) which implement the cache most recent bit > I aluded to above. Search for a subject of "Speed up link_mem_sections > during boot" and you will find them. I did add you to the Cc: list for > the next time I end up sending the set. > > My next task is to implement a x86_64 SGI UV specific chunk of code > to memory_block_size_bytes(). Would you consider adding that to your > patch set? I expect to have that either later today or early tomorrow. > No problem. I'm putting together a new patch set with updates from all of the comments now so go ahead and send it to me when you have it ready. -Nathan