From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758860Ab2IKLQI (ORCPT ); Tue, 11 Sep 2012 07:16:08 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:44844 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757783Ab2IKLQF (ORCPT ); Tue, 11 Sep 2012 07:16:05 -0400 From: Michal Nazarewicz To: Minchan Kim , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Kyungmin Park , Minchan Kim , Marek Szyprowski , Rik van Riel , Mel Gorman Subject: Re: [PATCH] mm: cma: Discard clean pages during contiguous allocation instead of migration In-Reply-To: <1347324112-14134-1-git-send-email-minchan@kernel.org> Organization: http://mina86.com/ References: <1347324112-14134-1-git-send-email-minchan@kernel.org> User-Agent: Notmuch/0.14+22~g8bdc16b (http://notmuchmail.org) Emacs/24.2.50.1 (x86_64-unknown-linux-gnu) X-Face: PbkBB1w#)bOqd`iCe"Ds{e+!C7`pkC9a|f)Qo^BMQvy\q5x3?vDQJeN(DS?|-^$uMti[3D*#^_Ts"pU$jBQLq~Ud6iNwAw_r_o_4]|JO?]}P_}Nc&"p#D(ZgUb4uCNPe7~a[DbPG0T~!&c.y$Ur,=N4RT>]dNpd;KFrfMCylc}gc??'U2j,!8%xdD Face: 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 X-PGP: 50751FF4 X-PGP-FP: AC1F 5F5C D418 88F8 CC84 5858 2060 4012 5075 1FF4 Date: Tue, 11 Sep 2012 13:15:56 +0200 Message-ID: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="=-=-=" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Tue, Sep 11 2012, Minchan Kim wrote: > This patch drops clean cache pages instead of migration during > alloc_contig_range() to minimise allocation latency by reducing the amount > of migration is necessary. It's useful for CMA because latency of migrati= on > is more important than evicting the background processes working set. > In addition, as pages are reclaimed then fewer free pages for migration > targets are required so it avoids memory reclaiming to get free pages, > which is a contributory factor to increased latency. > > * from v1 > * drop migrate_mode_t > * add reclaim_clean_pages_from_list instad of MIGRATE_DISCARD support -= Mel > > I measured elapsed time of __alloc_contig_migrate_range which migrates > 10M in 40M movable zone in QEMU machine. > > Before - 146ms, After - 7ms > > Cc: Marek Szyprowski > Cc: Michal Nazarewicz Acked-by: Michal Nazarewicz Thanks! --=20 Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=3D./ `o ..o | Computer Science, Micha=C5=82 =E2=80=9Cmina86=E2=80=9D Nazarewicz = (o o) ooo +------------------ooO--(_)--Ooo-- --=-=-= Content-Type: multipart/signed; boundary="==-=-="; micalg=pgp-sha1; protocol="application/pgp-signature" --==-=-= Content-Type: text/plain --==-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQIcBAEBAgAGBQJQTx1sAAoJECBgQBJQdR/0rcAP/34tPp7PJzehiwRqe7xBd/7W dmjRpYfGP08EvaxUgxPRdC/EAZTpgBy/jsVoa1vEXc1rAM3pCwKR3L5cTFd8xc4o /mKYzWAQy3N9zF/VrZiicZqLoguZJs9jqQoyqY9sO8qaMYqzQ92ETof1gsIGAv7J tx4UlECDu1tQrp9cDSMcP97Z1JnMh3hJ2V1cLrouW4nuQBCcImF3eR5NdEM84pEC rhBCmonm2X7SwPWkmc7tWXOEiqT3h9O7WGOl8Qc2JFDINVYXsGJFCwUC1LRIHqOt zFjwOmOeOdrqog6Wf2hRY7LpCzSjWsmz6MP747dJOZxlv+cdocIF6ibj6ZgoHjJj Ced0baWmH7fi963o9czgwO6JGeQ5swS06b+etFTwurQaRqNYc7nXhMoMZppaFuRq kEEfTbf2fkRONVoaWhUI7smSt7HH4zAjKlfN1YTXCy/fey2B37X7tBhQZsrGGwvm xn1zPXnxcrffu6L8afiPHqswFZCLX+Ta8KdPQvQP2ir23WPZ3P5f9VBt9e77uYng gu+2u8+zIalS9OPfZiUI2VB/xfR5TdR1HJZQHU4Xl/KzcWiQyjrKWamjnh3nxRfg G7BfNuwhZVnM+vDzjc+DHr56uJnxEAf9NMnKv6a9gXZRQHdI4QiImkAnZfhNtjSl /zy9TV9nwTkRcYhbKOHq =C9Mk -----END PGP SIGNATURE----- --==-=-=-- --=-=-=--