From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <dave@linux.vnet.ibm.com>
Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154])
	(using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
	(Client CN "e36.co.us.ibm.com", Issuer "Equifax" (verified OK))
	by ozlabs.org (Postfix) with ESMTPS id 0018FB70CD
	for <linuxppc-dev@ozlabs.org>; Thu, 12 Aug 2010 01:19:22 +1000 (EST)
Received: from d03relay01.boulder.ibm.com (d03relay01.boulder.ibm.com
	[9.17.195.226])
	by e36.co.us.ibm.com (8.14.4/8.13.1) with ESMTP id o7BFFNwi019293
	for <linuxppc-dev@ozlabs.org>; Wed, 11 Aug 2010 09:15:23 -0600
Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168])
	by d03relay01.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id
	o7BFItwm158716
	for <linuxppc-dev@ozlabs.org>; Wed, 11 Aug 2010 09:19:01 -0600
Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1])
	by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP
	id o7BFIsZq025170
	for <linuxppc-dev@ozlabs.org>; Wed, 11 Aug 2010 09:18:55 -0600
Subject: Re: [PATCH 0/8] v5 De-couple sysfs memory directories from memory
	sections
From: Dave Hansen <dave@linux.vnet.ibm.com>
To: Nathan Fontenot <nfont@austin.ibm.com>
In-Reply-To: <4C60407C.2080608@austin.ibm.com>
References: <4C60407C.2080608@austin.ibm.com>
Content-Type: text/plain; charset="ANSI_X3.4-1968"
Date: Wed, 11 Aug 2010 08:18:52 -0700
Message-ID: <1281539932.6988.39.camel@nimitz>
Mime-Version: 1.0
Cc: linux-mm@kvack.org, Greg KH <greg@kroah.com>, linux-kernel@vger.kernel.org,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>, linuxppc-dev@ozlabs.org
List-Id: Linux on PowerPC Developers Mail List <linuxppc-dev.lists.ozlabs.org>
List-Unsubscribe: <https://lists.ozlabs.org/options/linuxppc-dev>,
	<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=unsubscribe>
List-Archive: <http://lists.ozlabs.org/pipermail/linuxppc-dev>
List-Post: <mailto:linuxppc-dev@lists.ozlabs.org>
List-Help: <mailto:linuxppc-dev-request@lists.ozlabs.org?subject=help>
List-Subscribe: <https://lists.ozlabs.org/listinfo/linuxppc-dev>,
	<mailto:linuxppc-dev-request@lists.ozlabs.org?subject=subscribe>

On Mon, 2010-08-09 at 12:53 -0500, Nathan Fontenot wrote:
> This set of patches de-couples the idea that there is a single
> directory in sysfs for each memory section.  The intent of the
> patches is to reduce the number of sysfs directories created to
> resolve a boot-time performance issue.  On very large systems
> boot time are getting very long (as seen on powerpc hardware)
> due to the enormous number of sysfs directories being created.
> On a system with 1 TB of memory we create ~63,000 directories.
> For even larger systems boot times are being measured in hours. 

Hi Nathan,

The set is looking pretty good to me.  We _might_ want to up the ante in
the future and allow it to be even more dynamic than this, but this
looks like a good start to me.

BTW, have you taken a look at what the hotplug events look like if only
a single section (not filling up a whole block) is added?  

Feel free to add my:

Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>

-- Dave