WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-users

Re: [Xen-users] Seeing only 832 MB of 4 GB RAM on FC4 (2.6.12-1.1447_FC4

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-users] Seeing only 832 MB of 4 GB RAM on FC4 (2.6.12-1.1447_FC4xen0)
From: Ernst Bachmann <e.bachmann@xxxxxxxx>
Date: Fri, 16 Sep 2005 11:40:25 +0200
Delivery-date: Fri, 16 Sep 2005 09:38:16 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <432A908C.4090803@xxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <432A908C.4090803@xxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.8.1
On Friday 16 September 2005 11:29, thaiwiz Xen wrote:
> My machine is dual Xeon with 4GB RAM.
> When I boot with 2.6.12-1.1447_FC4smp, all 4GB RAM is seen and used
> normally.
> However, when I boot with 2.6.12-1.1447_FC4xen0, only 832MB RAM can be
> used. The warning message indicates  that I should use a HIGHMEM enabled
> kernel.
> 1. How can I define HIGHMEM?
> 2. Can it be done  with this binary FC4 release or I have to compile my
> own kernel and set HIGHMEM?
> 3. Anyone has  RPM built for this?

Even with Highmem enabled, you'll probably only have about 3GB of your ram 
usable. To get all of your ram, you'll have to use a PAE enabled kernel.
PAE uses paging to make the rest of your ram available, just like EMS did in 
the old DOS days...

The only way to get all 4GB available as "real ram" is to use a 64bit kernel 
(if your xeons have em64t).

PAE and 64bit support aren't available in xen-2.*, though, so you'll either 
have to live with 3GB ram or try xen-3.

/Ernst

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users

<Prev in Thread] Current Thread [Next in Thread>