From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 3 Nov 2005 17:06:26 -0800 (PST) From: Linus Torvalds Subject: Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19 In-Reply-To: <436AB241.2030403@yahoo.com.au> Message-ID: References: <4366C559.5090504@yahoo.com.au> <1130854224.14475.60.camel@localhost><20051101142959.GA9272@elte.hu> <1130856555.14475.77.camel@localhost><20051101150142.GA10636@elte.hu> <1130858580.14475.98.camel@localhost><20051102084946.GA3930@elte.hu> <436880B8.1050207@yahoo.com.au><1130923969.15627.11.camel@localhost> <43688B74.20002@yahoo.com.au><255360000.1130943722@[10.10.2.4]> <4369824E.2020407@yahoo.com.au> <306020000.1131032193@[10.10.2.4]> <1131032422.2839.8.camel@laptopd505.fenrus.org> <309420000.1131036740@[10.10.2.4]> <311050000.1131040276@[10.10.2.4]> <1131040786.2839.18.camel@laptopd505.fenrus.org> <312300000.1131041824@[10.1! 0.2.4]> <436AB241.2030403@yahoo.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: "Martin J. Bligh" , Arjan van de Ven , Mel Gorman , Dave Hansen , Ingo Molnar , Andrew Morton , kravetz@us.ibm.com, linux-mm , Linux Kernel Mailing List , lhms , Arjan van de Ven List-ID: On Fri, 4 Nov 2005, Nick Piggin wrote: > > Looks like ppc64 is getting 64K page support, at which point higher > order allocations (eg. for stacks) basically disappear don't they? Yes and no, HOWEVER, nobody sane will ever use 64kB pages on a general-purpose machine. 64kB pages are _only_ usable for databases, nothing else. Why? Do the math. Try to cache the whole kernel source tree in 4kB pages vs 64kB pages. See how the memory usage goes up by a factor of _four_. Linus -- 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