From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 14 Jul 2007 10:49:31 +0200 From: Nick Piggin Subject: Re: [PATCH 0/7] Sparsemem Virtual Memmap V5 Message-ID: <20070714084931.GE1198@wotan.suse.de> References: <617E1C2C70743745A92448908E030B2A01EA6524@scsmsx411.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: "Luck, Tony" , Andrew Morton , linux-mm@kvack.org, linux-arch@vger.kernel.org, Andy Whitcroft , Mel Gorman List-ID: On Fri, Jul 13, 2007 at 03:21:43PM -0700, Christoph Lameter wrote: > On Fri, 13 Jul 2007, Luck, Tony wrote: > > > 1) There is a small performance regression for ia64 (which is promised > > to go away when bigger pages are used for the mem_map, but I'd like to > > see that this really does fix the issue). > > The performance should be better than the existing one since we have even > less code here than discontig. We do no have to fetch the base anymore or > check boundaries (discontig was the baseline right?) but we have exactly > the same method of pfn_to_page and page_to_pfn as discontig/vmemmap. Isn't it still possible that you could have TLB pressure that would result in lower performance? I wonder why the large page support for ia64 was shelved? FWIW, since I was cc'ed for comments: I really like the patches as well although much of it is in memory model and arch code which I'm not so involved with. It should allow better performance, and unification of most if not all memory models which will be really nice. -- 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