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/
Home Products Support Community News


[Xen-users] dom0 hangs in xen 4.0.1-rc3-pre

To: xen-devel@xxxxxxxxxxxxxxxxxxx, xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] dom0 hangs in xen 4.0.1-rc3-pre
From: Jia Rao <rickenrao@xxxxxxxxx>
Date: Fri, 24 Sep 2010 00:22:21 -0400
Delivery-date: Thu, 23 Sep 2010 21:23:41 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:date:message-id :subject:from:to:content-type; bh=JNn/JKCx99TlGH3XSG9s034h1zlty8bZJpHrA2ms1+Q=; b=eaakkrBys8U9BfYXek+JgwfpRPAaEnsMvA4wMiWXVBHbp0wUI+XXw8oGkMQf+eOTyb 67qAv6JxZn0eyIqhp4pPG4RtSSVV1iHPPLhTm4/QLV/0X7LAOrflmPkNT3EzhWhMfIXl nRxESkYorwr8IRhgmOaZABnAMI/JvdW1aHJT0=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=VliHbHau7M51U6FRoOEdhBjgHU+in5AUlg4Sbb4rioiviaCJ8lCTlQfUQVqzVgBw0B yCgR1MhtPf9oNv/0QyA2UtXqBidgCj8AkDs0rp8ziU8zFJbVJLrXnVG3auFlifrvuBdq yojjN7Q2qsUoZPFsZ3gSUu0lR94CjR510SWNs=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
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/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
Hi all,

I saw reproducible hangs in dom0 when the system is under heavy load.

Testbed settings:
four dom0s share a nfs server for domU images. a total number of 24 domUs (6 domUs on each dom0). When the system under heavy load, busy processing e-commerce requests, one or two of the dom0s hanged. no input can be accepted and reboot is necessary. 

Anyone had the same experience? The causes I can come up are following:

1. nfs is not configured properly. But before I upgraded to xen 4, xen 3 worked pretty well.

2. the domU's are using tap2 disk. Any similar problem in testing tap2?

3. Or the problem is from the new pvops kernel ? All the domU are cpu intensive and not generating a lot of IOs.

Unfortunately, dom0's dmesg and xm log recorded nothing about the hangs.


Xen: 4.0.1-rc3-pre
dom0: centos pvops 8G, 8 cores
domU: PV kernel 1G, 4 VCPU
NFS server: 8G, 8 cores, 4-disk RAID 5 nfs version 3 over TCP, rw size 4K
Interconnect: Gigabyte Ethernet.

Thanks a lot !
Xen-users mailing list