From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755837Ab2GXWrS (ORCPT ); Tue, 24 Jul 2012 18:47:18 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:45139 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755631Ab2GXWrQ (ORCPT ); Tue, 24 Jul 2012 18:47:16 -0400 Date: Tue, 24 Jul 2012 15:47:12 -0700 From: Greg KH To: Mel Gorman Cc: Stable , Linux-MM , LKML Subject: Re: [PATCH 03/34] mm: Reduce the amount of work done when updating min_free_kbytes Message-ID: <20120724224712.GB4245@kroah.com> References: <1343050727-3045-1-git-send-email-mgorman@suse.de> <1343050727-3045-4-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1343050727-3045-4-git-send-email-mgorman@suse.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 23, 2012 at 02:38:16PM +0100, Mel Gorman wrote: > commit 938929f14cb595f43cd1a4e63e22d36cab1e4a1f upstream. > > Stable note: Fixes https://bugzilla.novell.com/show_bug.cgi?id=726210 . > Large machines with 1TB or more of RAM take a long time to boot > without this patch and may spew out soft lockup warnings. In comparing this with the upstream version, you have a few different coding style differences, but no real content difference. Why? > > When min_free_kbytes is updated blocks marked MIGRATE_RESERVE are > updated. Ordinarily, this work is unnoticable as it happens early > in boot. However, on large machines with 1TB of memory, this can take > a considerable time when NUMA distances are taken into account. The bulk > of the work is done by pageblock_is_reserved() which examines the > metadata for almost every page in the system. Currently, we are doing > this far more than necessary as it is only required while there are > still blocks to be marked MIGRATE_RESERVE. This patch significantly > reduces the amount of work done by setup_zone_migrate_reserve() > improving boot times on 1TB machines. > > [akpm@linux-foundation.org: coding-style fixes] I'm guessing you didn't pick these up? Anyway, I've taken it now as the original one from Linus's tree, hopefully this doesn't burn me later in the series... thanks, greg k-h From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx140.postini.com [74.125.245.140]) by kanga.kvack.org (Postfix) with SMTP id B142E6B0044 for ; Tue, 24 Jul 2012 18:47:16 -0400 (EDT) Received: by pbbrp2 with SMTP id rp2so348560pbb.14 for ; Tue, 24 Jul 2012 15:47:16 -0700 (PDT) Date: Tue, 24 Jul 2012 15:47:12 -0700 From: Greg KH Subject: Re: [PATCH 03/34] mm: Reduce the amount of work done when updating min_free_kbytes Message-ID: <20120724224712.GB4245@kroah.com> References: <1343050727-3045-1-git-send-email-mgorman@suse.de> <1343050727-3045-4-git-send-email-mgorman@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1343050727-3045-4-git-send-email-mgorman@suse.de> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Stable , Linux-MM , LKML On Mon, Jul 23, 2012 at 02:38:16PM +0100, Mel Gorman wrote: > commit 938929f14cb595f43cd1a4e63e22d36cab1e4a1f upstream. > > Stable note: Fixes https://bugzilla.novell.com/show_bug.cgi?id=726210 . > Large machines with 1TB or more of RAM take a long time to boot > without this patch and may spew out soft lockup warnings. In comparing this with the upstream version, you have a few different coding style differences, but no real content difference. Why? > > When min_free_kbytes is updated blocks marked MIGRATE_RESERVE are > updated. Ordinarily, this work is unnoticable as it happens early > in boot. However, on large machines with 1TB of memory, this can take > a considerable time when NUMA distances are taken into account. The bulk > of the work is done by pageblock_is_reserved() which examines the > metadata for almost every page in the system. Currently, we are doing > this far more than necessary as it is only required while there are > still blocks to be marked MIGRATE_RESERVE. This patch significantly > reduces the amount of work done by setup_zone_migrate_reserve() > improving boot times on 1TB machines. > > [akpm@linux-foundation.org: coding-style fixes] I'm guessing you didn't pick these up? Anyway, I've taken it now as the original one from Linus's tree, hopefully this doesn't burn me later in the series... thanks, greg k-h -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org