From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx128.postini.com [74.125.245.128]) by kanga.kvack.org (Postfix) with SMTP id AFE716B0044 for ; Thu, 29 Mar 2012 15:43:16 -0400 (EDT) Received: by yenm8 with SMTP id m8so2283133yen.14 for ; Thu, 29 Mar 2012 12:43:15 -0700 (PDT) Message-ID: <4F74BB67.30703@gmail.com> Date: Thu, 29 Mar 2012 15:43:35 -0400 From: KOSAKI Motohiro MIME-Version: 1.0 Subject: Re: [PATCH -mm] do_migrate_pages() calls migrate_to_node() even if task is already on a correct node References: <4F6B6BFF.1020701@redhat.com> <4F6B7358.60800@gmail.com> <4F6B7854.1040203@redhat.com> <4F74A344.7070805@redhat.com> In-Reply-To: <4F74A344.7070805@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: lwoodman@redhat.com Cc: Christoph Lameter , KOSAKI Motohiro , linux-mm@kvack.org, Linux Kernel Mailing List , Andrew Morton , Rik van Riel , Motohiro Kosaki kosaki.motohiro@gmail.com (3/29/12 2:00 PM), Larry Woodman wrote: > On 03/22/2012 03:30 PM, Christoph Lameter wrote: >> On Thu, 22 Mar 2012, Larry Woodman wrote: >> >>>> Application may manage their locality given a range of nodes and each of >>>> the x .. x+n nodes has their particular purpose. >>> So to be clear on this, in that case the intention would be move 3 to 4, 4 to >>> 5 and 5 to 6 >>> to keep the node ordering the same? >> Yup. Have a look at do_migrate_pages and the descrition in the comment by >> there by Paul Jackson. >> >> > Christoph and others what do you think about this??? > > > for_each_node_mask(s, tmp) { >+ >+ /* IFF there is an equal number of source and >+ * destination nodes, maintain relative node distance >+ * even when source and destination nodes overlap. >+ * However, when the node weight is unequal, never move >+ * memory out of any destination nodes */ >+ if ((nodes_weight(*from_nodes) != nodes_weight(*to_nodes)) && >+ (node_isset(s, *to_nodes))) >+ continue; >+ > d = node_remap(s, *from_nodes, *to_nodes); > if (s == d) > continue; I'm confused. Could you please explain why you choose nodes_weight()? On my first impression, it seems almostly unrelated factor. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org