From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate2.de.ibm.com (8.12.10/8.12.10) with ESMTP id j95Hkad7107336 for ; Wed, 5 Oct 2005 17:46:36 GMT Received: from d12av02.megacenter.de.ibm.com (d12av02.megacenter.de.ibm.com [9.149.165.228]) by d12nrmr1607.megacenter.de.ibm.com (8.12.10/NCO/VERS6.7) with ESMTP id j95HkZvk163648 for ; Wed, 5 Oct 2005 19:46:35 +0200 Received: from d12av02.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av02.megacenter.de.ibm.com (8.12.11/8.13.3) with ESMTP id j95HkZHA008184 for ; Wed, 5 Oct 2005 19:46:35 +0200 Date: Wed, 5 Oct 2005 19:45:42 +0200 From: Heiko Carstens Subject: Re: sparsemem & sparsemem extreme question Message-ID: <20051005174542.GB10204@osiris.ibm.com> References: <20051004065030.GA21741@osiris.boeblingen.de.ibm.com> <1128442502.20208.6.camel@localhost> <20051005063909.GA9699@osiris.boeblingen.de.ibm.com> <1128527554.26009.2.camel@localhost> <20051005155823.GA10119@osiris.ibm.com> <1128528340.26009.8.camel@localhost> <20051005161009.GA10146@osiris.ibm.com> <1128529222.26009.16.camel@localhost> <20051005171230.GA10204@osiris.ibm.com> <1128532809.26009.39.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1128532809.26009.39.camel@localhost> Sender: owner-linux-mm@kvack.org Return-Path: To: Dave Hansen Cc: linux-mm List-ID: > > Anything specific you need to know about the memory layout? > How sparse is it? How few present pages can be there be in a worst-case > physical area? Worst case that is already currently valid is that you can have 1 MB segments whereever you want in address space. For instance I just configured a virtual machine that has the following memory layout: Address Range ----------------------------------- 0000000000000000 - 00000000000FFFFF 000000FFC0000000 - 000000FFC00FFFFF Even though it's currently not possible to define memory segments above 1TB, this limit is likely to go away. In addition if running in a logical partition we always have a small gap at the 2GB barrier. Not sure how large that gap is, I'll check tomorrow. Heiko -- 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