From owner-freebsd-hackers Thu Dec 5 18:48:43 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 03B7937B401 for ; Thu, 5 Dec 2002 18:48:43 -0800 (PST) Received: from HAL9000.homeunix.com (12-232-220-15.client.attbi.com [12.232.220.15]) by mx1.FreeBSD.org (Postfix) with ESMTP id 33ABA43EC2 for ; Thu, 5 Dec 2002 18:48:42 -0800 (PST) (envelope-from dschultz@uclink.Berkeley.EDU) Received: from HAL9000.homeunix.com (localhost [127.0.0.1]) by HAL9000.homeunix.com (8.12.6/8.12.5) with ESMTP id gB62meJt014714; Thu, 5 Dec 2002 18:48:40 -0800 (PST) (envelope-from dschultz@uclink.Berkeley.EDU) Received: (from das@localhost) by HAL9000.homeunix.com (8.12.6/8.12.5/Submit) id gB62mdrx014713; Thu, 5 Dec 2002 18:48:39 -0800 (PST) (envelope-from dschultz@uclink.Berkeley.EDU) Date: Thu, 5 Dec 2002 18:48:39 -0800 From: David Schultz To: Gary Thorpe Cc: Terry Lambert , freebsd-hackers@FreeBSD.ORG Subject: Re: maxusers and random system freezes Message-ID: <20021206024839.GA14624@HAL9000.homeunix.com> Mail-Followup-To: Gary Thorpe , Terry Lambert , freebsd-hackers@FreeBSD.ORG References: <3DEEB45A.BEDF8EA5@mindspring.com> <20021205194604.79160.qmail@web41207.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20021205194604.79160.qmail@web41207.mail.yahoo.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Thus spake Gary Thorpe : > As far as I know, Linux maps all the memory in the machine into the > kernel address space, so there is never a problem of it running out > while there is free memory (if you run out of it, there isn't any at > all left in the machine). It also permits the kernel to directly modify > processes' address spaces??? Linux used to do that, but AFAIK it doesn't anymore. Mapping all of physical memory into KVA simplifies copyin() and copyout(), but it restricts the amount of usable physical memory to well under 4GB. They couldn't possibly have kept doing things this way when they added support for all of the bank switching crap on i386. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message