From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 15 Feb 2007 14:53:46 -0800 (PST) From: Christoph Lameter Subject: Re: [RFC] Remove unswappable anonymous pages off the LRU In-Reply-To: <45D4E3B6.8050009@redhat.com> Message-ID: References: <45D4DF28.7070409@redhat.com> <45D4E3B6.8050009@redhat.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Rik van Riel Cc: akpm@linux-foundation.org, linux-mm@kvack.org, Nick Piggin , Peter Zijlstra , KAMEZAWA Hiroyuki , "Martin J. Bligh" List-ID: On Thu, 15 Feb 2007, Rik van Riel wrote: > Christoph Lameter wrote: > > On Thu, 15 Feb 2007, Rik van Riel wrote: > > > > > Running out of swap is a temporary condition. > > > You need to have some way for those pages to > > > make it back onto the LRU list when swap > > > becomes available. > > > > Yup any ideas how? > > Not really. Maybe its then best to not move the pages off the LRU when there is some swap available. But even if there is no swap available: The user could add some later. So there is really no criterion for removing anonymous pages off the LRU. We would at least need some list of mlocked pages in orderto feed them back to the LRU. > > > For example, we could try to reclaim the swap > > > space of every page that we scan on the active > > > list - when swap space starts getting tight. > > > > Good idea. > > I suspect this will be a better approach. That way > the least used pages can cycle into swap space, and > the more used pages can be in RAM. > > The only reason pages are unswappable when we run > out of swap is that we don't free up the swap space > used by pages that are in memory. Well that is another project and not moving pages off the LRU. -- 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