From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 8 Feb 2008 18:16:16 -0800 (PST) From: Christoph Lameter Subject: Re: [ofa-general] Re: [patch 0/6] MMU Notifiers V6 In-Reply-To: <20080209015659.GC7051@v2.random> Message-ID: References: <20080208234302.GH26564@sgi.com> <20080208155641.2258ad2c.akpm@linux-foundation.org> <20080209012446.GB7051@v2.random> <20080209015659.GC7051@v2.random> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrea Arcangeli Cc: Roland Dreier , a.p.zijlstra@chello.nl, izike@qumranet.com, steiner@sgi.com, linux-kernel@vger.kernel.org, avi@qumranet.com, linux-mm@kvack.org, daniel.blueman@quadrics.com, Robin Holt , general@lists.openfabrics.org, Andrew Morton , kvm-devel@lists.sourceforge.net, Rik van Riel List-ID: On Sat, 9 Feb 2008, Andrea Arcangeli wrote: > The VM shouldn't break if try_to_unmap doesn't actually make the page > freeable for whatever reason. Permanent pins shouldn't happen anyway, VM is livelocking if too many page are pinned that way right now. The higher the processors per node the higher the risk of livelock because more processors are in the process of cycling through pages that have an elevated refcount. > so defining an ad-hoc API for that doesn't sound too appealing. Not > sure if old hardware deserves those special lru-size-reduction > optimizations but it's not my call (certainly swapoff/mlock would get > higher priority in that lru-size-reduction area). Rik has a patchset under development that addresses issues like this. The elevated refcount pin problem is not really relevant to the patchset we are discussing here. -- 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