From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Subject: Re: [PATCH/RFC] Shared page tables Date: Tue, 24 Jan 2006 01:39:46 +0100 References: <200601231758.08397.raybry@mpdtxmail.amd.com> <200601231816.38942.raybry@mpdtxmail.amd.com> In-Reply-To: <200601231816.38942.raybry@mpdtxmail.amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200601240139.46751.ak@suse.de> Sender: owner-linux-mm@kvack.org Return-Path: To: Ray Bryant Cc: Dave McCracken , Robin Holt , Hugh Dickins , Linux Kernel , Linux Memory Management List-ID: On Tuesday 24 January 2006 01:16, Ray Bryant wrote: > On Monday 23 January 2006 17:58, Ray Bryant wrote: > > > > ... And what kind of alignment constraints do we end up > > under in order to make the sharing happen? (My guess would be that there > > aren't any such constraints (well, page alignment.. :-) if we are just > > sharing pte's.) > > > > Oh, obviously that is not right as you have to share full pte pages. So on > x86_64 I'm guessing one needs 2MB alignment in order to get the sharing to > kick in, since a pte page maps 512 pages of 4 KB each. The new randomized mmaps will likely actively sabotate such alignment. I just added them for x86-64. -Andi -- 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