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-devel

[Xen-devel] XEN problems when using large # of NICs in domain U

To: xen-devel@xxxxxxxxxxxxxxxxxxxxx
Subject: [Xen-devel] XEN problems when using large # of NICs in domain U
From: Eric Tessler <maiden1134@xxxxxxxxx>
Date: Fri, 11 Feb 2005 17:19:23 -0800 (PST)
Comment: DomainKeys? See http://antispam.yahoo.com/domainkeys
Delivery-date: Sat, 12 Feb 2005 01:23:43 +0000
Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; b=fFwPVXuPZZXy3LVgItmwRTDU2/ztIer+hPyalNPsQetgTecXgnoS2DIQWciaSuy1gHlayZLuM4aDys8qqytdbfLpNFmuNZv/v3/MOaWONWHBn2dxOwOL0dNOYGBfYXiIAI1dV627ibqn79UyE3IglpWtGLwglKwiNHTzM0clgJ0= ;
Envelope-to: xen+James.Bulpin@xxxxxxxxxxxx
List-archive: <http://sourceforge.net/mailarchive/forum.php?forum=xen-devel>
List-help: <mailto:xen-devel-request@lists.sourceforge.net?subject=help>
List-id: List for Xen developers <xen-devel.lists.sourceforge.net>
List-post: <mailto:xen-devel@lists.sourceforge.net>
List-subscribe: <https://lists.sourceforge.net/lists/listinfo/xen-devel>, <mailto:xen-devel-request@lists.sourceforge.net?subject=subscribe>
List-unsubscribe: <https://lists.sourceforge.net/lists/listinfo/xen-devel>, <mailto:xen-devel-request@lists.sourceforge.net?subject=unsubscribe>
Sender: xen-devel-admin@xxxxxxxxxxxxxxxxxxxxx
 
I am trying to test XEN with a large # of NICs in domain U.  I configured a single domain U to have 128 NICs (by simply setting the # of NICs to 128 in the domain U configuration file). When I try to create the domain using "xm create domainU -c", the domain starts to boot but then hangs when it reaches the stage of initializing the virtual NICs (xen_net: Initialising virtual ethernet driver).  After about 30 seconds, the machine reboots on its own.
 
If I set the # of NICs to 512, domain U does not boot and instead I get the following error message from xm: "Error: Callback timed out".  The machine does not reboot in this case.
 
The magic number appears to be 122 - I can set the # of NICs to 122 and domain U boots with no problems.  If I go to 123, it hangs and reboots my machine.  I can also configure 2 domain U's each with 61 NICs and that works fine.  However if I increase one of them to 62 that domain fails to start and my machine reboots (so the total is 123).  This also implies that the maximum # of domain U's possible on one machine is 122.
 
This does not appear to be a problem with the bridge - I did a little debugging and it turns out that in all cases XEN sucessfully instantiates the back-end network drivers and adds them to the bridge (all VIFx.y interfaces are visable and registered with the bridge).  This could be a problem with the front-end network drivers. I don't see any failure debug ouput in any of the XEN logs.
 
I tried all tests on 3 different physical machines with different amounts of memory.  The domain U's were configured with different amounts of memory (from 64MB to 512MB).  This does not appear to be a memory issue.
 
Has anyone else tried this or have any other information on why this may be occuring?
 
Eric
 


Do you Yahoo!?
Yahoo! Search presents - Jib Jab's 'Second Term'
<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-devel] XEN problems when using large # of NICs in domain U, Eric Tessler <=