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

[Xen-users] Save/restore broken in 3.0.2-2?

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] Save/restore broken in 3.0.2-2?
From: "Simon Graham" <simgrxp@xxxxxxxxx>
Date: Mon, 8 May 2006 10:39:15 -0400
Delivery-date: Mon, 08 May 2006 08:50:06 -0700
Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:mime-version:content-type; b=ehZSYvlL3TJHytKKjhHWr7u7Cn9HpZgk93Flk6bTI+Nz2WzNTjlRjqXexU9ZddZJxDUvTJlGF32pfPioMROqWYGllc6ZRLF6ZHovEt3jhdbMUHIGw+ZAJ2YgtGWawjEV/kxyvd/E5UIFasjZ+YU/XLjV4lhlCK9Y2Q0JJe3uFyQ=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
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>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
I've been experimenting with using save/restore as a poor-mans migration on 3.0.2-2 and have experienced some real problems with the guests hanging when they are restored. In the end, I was able to repro this simply executing 'xm save' and then 'xm restore' on the same system -- the symptom is that the the restored guest is apparently running (for example, I can ping it) but anything that requires access to the disk hangs up.
 
Eventually, I dumped the guest and used crash to look at what was going on and I can see that the VBD front end driver is hung waiting for disk I/O to complete -- it seems to reconnect to the backend OK and re-issues I/O that was outstanding when the guest was saved (in all cases, there seems to be a single I/O outstanding when the save is done - a syslog write) and even carries on and issues more disk I/O requests _but_ none of them complete.
 
I should say that both Dom0 and DomU are 3.0.2-2 on top of vanilla 2.6.16 kernels.
 
Anyone know if this is a known issue with the release? Or suggest further investigation required?
Simon
 
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-users] Save/restore broken in 3.0.2-2?, Simon Graham <=