From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 04 Jan 2005 23:42:07 +0900 (JST) Message-Id: <20050104.234207.74734492.taka@valinux.co.jp> Subject: Re: page migration From: Hirokazu Takahashi In-Reply-To: <41D9A7DB.2020306@sgi.com> References: <41D99743.5000601@sgi.com> <1104781061.25994.19.camel@localhost> <41D9A7DB.2020306@sgi.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: raybry@sgi.com Cc: haveblue@us.ibm.com, marcelo.tosatti@cyclades.com, linux-mm@kvack.org List-ID: Hi Ray, > >>Of course, the "standalone" memory migration stuff makes most sense on NUMA, > >>and there is some minor interface changes there to support that (i. e. consider: > >> > >>migrate_onepage(page); > >> > >>vs > >> > >>migrate_onepage_node(page, node); > >> > >>what the latter does is to call alloc_pages_node() instead of > >>page_cache_alloc() to get the new page.) > > > > > > We might as well just change all of the users over to the NUMA version > > from the start. Having 2 different functions just causes confusion. > > > > Yes, especially since alloc_pages_node() is defined regardless of whether > NUMA is defined (I've found out by some code inspection). So in the > non-DISCONTIGMEM cases, the node argument would just be ignored. I'll > put together a patch that moves the interface over to > > migrate_onepage(page, node) > > and fixes up the callers in the memory hotplug patches. I also think we should rewrite page allocation in the memory migration code, as the latest -mm tree includes NUMA aware page allocator. I guess you should also care about mm/mempolicy.c and expand it for your purpose. If memory migration is called after moving a process, a new page would be allocated form a proper node automatically. Have you checked mm/mempolicy.c? Thanks, Hirokazu Takahashi. -- 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: aart@kvack.org