From owner-freebsd-arch@FreeBSD.ORG Sun Nov 14 02:19:39 2004 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id D878D16A4CE; Sun, 14 Nov 2004 02:19:39 +0000 (GMT) Received: from apollo.backplane.com (apollo.backplane.com [216.240.41.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9B6D243D4C; Sun, 14 Nov 2004 02:19:39 +0000 (GMT) (envelope-from dillon@apollo.backplane.com) Received: from apollo.backplane.com (localhost [127.0.0.1]) iAE2JdcW003118; Sat, 13 Nov 2004 18:19:39 -0800 (PST) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.12.9p2/8.12.9/Submit) id iAE2Jd8Z003117; Sat, 13 Nov 2004 18:19:39 -0800 (PST) (envelope-from dillon) Date: Sat, 13 Nov 2004 18:19:39 -0800 (PST) From: Matthew Dillon Message-Id: <200411140219.iAE2Jd8Z003117@apollo.backplane.com> To: Peter Wemm References: <20041111030035.GA70923@VARK.MIT.EDU> <200411131600.55982.peter@wemm.org> cc: arch@freebsd.org cc: David Schultz cc: freebsd-arch@freebsd.org Subject: Re: U Area Removal X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 14 Nov 2004 02:19:40 -0000 :On Wednesday 10 November 2004 07:00 pm, David Schultz wrote: : :> I propose to remove the ability to swap the U area, allocating :> p_stats from malloced memory instead. Medium-term scheduling and :> swapping of kernel stacks would be retained. : :For what its worth, I support this change. With the plimit/pstats fixes :of course. :-) : :-- :Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com I've had u-area swapping turned off almost from day-1 in DragonFly with no adverse effects. I'm still using the area for a stack so I haven't completely ripped it out, but as far as the swapping goes I think it's a good idea to rip it out. It does significantly simplify certain aspects of the kernel. -Matt Matthew Dillon