Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932231Ab0LMQyQ (ORCPT ); Mon, 13 Dec 2010 11:54:16 -0500 Received: from mail-pw0-f46.google.com ([209.85.160.46]:36937 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754018Ab0LMQyP (ORCPT ); Mon, 13 Dec 2010 11:54:15 -0500 Date: Mon, 13 Dec 2010 09:54:05 -0700 From: Eric B Munson To: Mel Gorman Cc: Simon Kirby , KOSAKI Motohiro , Shaohua Li , Dave Hansen , Johannes Weiner , Andrew Morton , linux-mm , linux-kernel Subject: Re: [PATCH 1/6] mm: kswapd: Stop high-order balancing when any suitable zone is balanced Message-ID: <20101213165405.GA3401@mgebm.net> References: <1291893500-12342-1-git-send-email-mel@csn.ul.ie> <1291893500-12342-2-git-send-email-mel@csn.ul.ie> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="x+6KMIRAuhnl3hBn" Content-Disposition: inline In-Reply-To: <1291893500-12342-2-git-send-email-mel@csn.ul.ie> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2013 Lines: 53 --x+6KMIRAuhnl3hBn Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, 09 Dec 2010, Mel Gorman wrote: > When the allocator enters its slow path, kswapd is woken up to balance the > node. It continues working until all zones within the node are balanced. = For > order-0 allocations, this makes perfect sense but for higher orders it can > have unintended side-effects. If the zone sizes are imbalanced, kswapd may > reclaim heavily within a smaller zone discarding an excessive number of > pages. The user-visible behaviour is that kswapd is awake and reclaiming > even though plenty of pages are free from a suitable zone. >=20 > This patch alters the "balance" logic for high-order reclaim allowing ksw= apd > to stop if any suitable zone becomes balanced to reduce the number of pag= es > it reclaims from other zones. kswapd still tries to ensure that order-0 > watermarks for all zones are met before sleeping. >=20 > Signed-off-by: Mel Gorman Looks good to me. Reviewed-by: Eric B Munson --x+6KMIRAuhnl3hBn Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQEcBAEBAgAGBQJNBk+tAAoJEH65iIruGRnN2UoIAJAVhQyLzVEJO3bRcprOcF32 6nu2UwoACYmA3ge+eMjaOdqaZ/GW2XNIW6n211oGUmZt1ttRihOxRPDhxqUkCYf6 O32MwxEdSf61I1icQlEnj7+fP0UMES8h5e0hi2Aq3LXo82aTgUa4CuCeI8RqMpMv lcGm4/dilzG0l4TNt0GfxiI4xeZu5+A2mDAsVyTd+77d3A0GxszptXlKf3NbSKJn au5sCS5E+aqHNkqXfrTzPM0HzxXeVvd12RZJYiF6WfTXs29CV0cHIs/gHAb5cYlu b4yQX20HId2YuFjl5UhszOSXYj2Gsw4Bhk/ZArKWMdAqQCkui+njxql+uHjym6w= =zXJi -----END PGP SIGNATURE----- --x+6KMIRAuhnl3hBn-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/