From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 8 Feb 2008 15:32:19 -0800 (PST) From: Christoph Lameter Subject: Re: [patch 0/6] MMU Notifiers V6 In-Reply-To: <20080208142315.7fe4b95e.akpm@linux-foundation.org> Message-ID: References: <20080208220616.089936205@sgi.com> <20080208142315.7fe4b95e.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: andrea@qumranet.com, holt@sgi.com, avi@qumranet.com, izike@qumranet.com, kvm-devel@lists.sourceforge.net, a.p.zijlstra@chello.nl, steiner@sgi.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, daniel.blueman@quadrics.com, general@lists.openfabrics.org List-ID: On Fri, 8 Feb 2008, Andrew Morton wrote: > What about ib_umem_get()? Ok. It pins using an elevated refcount. Same as XPmem right now. With that we effectively pin a page (page migration will fail) but we will continually be reclaiming the page and may repeatedly try to move it. We have issues with XPmem causing too many pages to be pinned and thus the OOM getting into weird behavior modes (OOM or stop lru scanning due to all_reclaimable set). An elevated refcount will also not be noticed by any of the schemes under consideration to improve LRU scanning performance. -- 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