From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 23 Oct 2000 18:13:48 -0200 (BRDT) From: Rik van Riel Subject: Re: Another wish item for your TODO list... In-Reply-To: <20001023203853.A3295@redhat.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: "Stephen C. Tweedie" Cc: linux-mm@kvack.org List-ID: On Mon, 23 Oct 2000, Stephen C. Tweedie wrote: > On Mon, Oct 23, 2000 at 04:07:02PM -0200, Rik van Riel wrote: > > > > It's an optimisation in CPU time as much as for anything else: > > > there's just no point in doing expensive memory balancing/aging > > > for pages which we know are next to useless. > > > > The problem here is that we shouldn't remove the pages which are > > in the current readahead window, as those /will/ most likely be > > used in the near future. > > It probably only makes real sense to do this for inodes which > are not in use, anyway, which avoids that problem completely. FreeBSD has a neat solution for this: - if the memory item (file, shm segment, ...) is in use, move the page to the inactive list (equivalent to our inactive_dirty) - if the item isn't in use, move the page to the cache list (equivalent to our inactive_clean list) We could extend this by moving *every* page of an item which isn't in use to the inactive_clean list once we move ONE page of such an item to that list (or reclaim it?). [IMHO we don't want to free the page ... no need to throw away the data in the page too soon] regards, Rik -- "What you're running that piece of shit Gnome?!?!" -- Miguel de Icaza, UKUUG 2000 http://www.conectiva.com/ http://www.surriel.com/ -- 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.eu.org/Linux-MM/