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-ia64-devel

Re: [Xen-ia64-devel] VHPT implementation issues

To: "Magenheimer, Dan \(HP Labs Fort Collins\)" <dan.magenheimer@xxxxxx>
Subject: Re: [Xen-ia64-devel] VHPT implementation issues
From: Arun Sharma <arun.sharma@xxxxxxxxx>
Date: Thu, 02 Jun 2005 18:41:34 -0700
Cc: Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Fri, 03 Jun 2005 01:40:45 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <516F50407E01324991DD6D07B0531AD542D47F@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-ia64-devel-request@lists.xensource.com?subject=help>
List-id: DIscussion of the ia64 port of Xen <xen-ia64-devel.lists.xensource.com>
List-post: <mailto:xen-ia64-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=unsubscribe>
References: <516F50407E01324991DD6D07B0531AD542D47F@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx>
Sender: xen-ia64-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla Thunderbird 1.0.2 (Windows/20050317)
Magenheimer, Dan (HP Labs Fort Collins) wrote:
We first eliminated 1 and 3 as they have scalability issues on large scale SMP systems.


I forgot to ask at the time...

Could you explain the scalability issues more?

I'm assuming that you'll implement collision chains. If you don't implement collision chains, then it becomes hard to provide the architectural guarantees for forward progress.

If you do implement collision chains, then you'll have to lock them and this might end up with too much serialization.

Also, how are per-cpu mappings in the guest going to be handled in a global VHPT?

I don't have hard data comparing the two approaches - but above are some of the reasons we used to rule it out.

        -Arun

_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel

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