From owner-freebsd-hackers  Tue Apr 22 23:23:40 1997
Return-Path: <owner-hackers>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.5/8.8.5) id XAA10393
          for hackers-outgoing; Tue, 22 Apr 1997 23:23:40 -0700 (PDT)
Received: from root.com (implode.root.com [198.145.90.17])
          by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id XAA10387
          for <hackers@freebsd.org>; Tue, 22 Apr 1997 23:23:37 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1]) by root.com (8.8.5/8.6.5) with SMTP id XAA01951; Tue, 22 Apr 1997 23:24:59 -0700 (PDT)
Message-Id: <199704230624.XAA01951@root.com>
X-Authentication-Warning: implode.root.com: localhost [127.0.0.1] didn't use HELO protocol
To: "David Langford" <langfod@dihelix.com>
cc: msmith@atrad.adelaide.edu.au (Michael Smith), joe@via.net,
        mrcpu@cdsnet.net, hackers@freebsd.org
Subject: Re: Can't put 512MB ram in box ... Extended memory question. 
In-reply-to: Your message of "Tue, 22 Apr 1997 18:11:11 -1000."
             <199704230411.SAA01625@caliban.dihelix.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Tue, 22 Apr 1997 23:24:59 -0700
Sender: owner-hackers@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

>Is it my imagination or doesnt BSDI handle this fairly automagically?
>
>Also what are the consequences of setting MAXMEM to a high number
>even on low memory machine. 
>I thought that I saw the GENERIC kernel et at 128K.

   Yes, you can do that. There is a stupid bug in the reporting of memory
holes that causes a "Physical memory hole(s):" line to come out, but
that is quite harmless. Otherwise, if it works at all then it will work
just fine. Michael is correct, though; some motherboards will reset or
get NMIs if you access non-existent memory, which is why we don't do
speculative memory probing by default.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project