From owner-freebsd-current Mon Dec 4 13: 0: 0 2000 From owner-freebsd-current@FreeBSD.ORG Mon Dec 4 12:59:56 2000 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mail.du.gtn.com (mail.du.gtn.com [194.77.9.57]) by hub.freebsd.org (Postfix) with ESMTP id D07D737B401 for ; Mon, 4 Dec 2000 12:59:55 -0800 (PST) Received: from mail.cicely.de (cicely.de [194.231.9.142]) by mail.du.gtn.com (8.11.0.Beta3/8.11.0.Beta3) with ESMTP id eB4KxDP07949 (using TLSv1/SSLv3 with cipher EDH-RSA-DES-CBC3-SHA (168 bits) verified OK); Mon, 4 Dec 2000 21:59:15 +0100 (MET) Received: from cicely8.cicely.de (cicely8.cicely.de [10.1.2.10]) by mail.cicely.de (8.11.0.Beta1/8.11.0.Beta1) with ESMTP id eB4Kvqa83905 (using TLSv1/SSLv3 with cipher EDH-RSA-DES-CBC3-SHA (168 bits) verified NO); Mon, 4 Dec 2000 21:59:21 +0100 (CET) Received: (from ticso@localhost) by cicely8.cicely.de (8.11.0/8.9.2) id eA5GvkL42412; Sun, 5 Nov 2000 17:57:46 +0100 (CET) (envelope-from ticso) Date: Sun, 5 Nov 2000 17:57:46 +0100 From: Bernd Walter To: David Greenman Cc: janb@cs.utep.edu, freebsd-current@FreeBSD.ORG Subject: Re: current paging strategy Message-ID: <20001105175745.A42346@cicely8.cicely.de> References: <200011020845.AAA13439@implode.root.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0.1i In-Reply-To: <200011020845.AAA13439@implode.root.com>; from dg@root.com on Thu, Nov 02, 2000 at 12:45:30AM -0800 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thu, Nov 02, 2000 at 12:45:30AM -0800, David Greenman wrote: > >Interesting. THis needs about two bytes per page for the counter? > > Actually, we found that a single byte per page was sufficient. Pages tended > to be either heavily accessed or rarely accessed. Even in the unusual case > where all pages are frequently accessed, the page reclaim rate (and thus > adjustment rate of the page references count) increases high enough to still > provide for a decent distribution of the counters and for the page LOU to be > effective. One byte sounds good for i386. Maybe it makes sense to have it 4 or 8 byte on risc platforms. I wonder if it's a critical path and if there are more of this in the kernel source. -- B.Walter COSMO-Project http://www.cosmo-project.de ticso@cicely.de Usergroup info@cosmo-project.de To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message