[Xen-users] Re: Memory squeeze in netback driver

["Scott Moe" <smoe868@xxxxxxxxx>]

Before I had had no dom0_mem argument. With Xen 2 I had to specifiy the Dom0 memory size and I liked the idea of dynamically resizing with Xen 3.  Right now I've got both dom0_mem in grub/menu.list and dom0-min-mem in 
xend-config.sxp set to the same value. So far so good. I am at just over 20 hours of uptime with no memory squeeze error messages. 

I would feel better about this fix if I understood the problem.  After what I have read about it in the last few days, now I am thinking it comes from the dynamic resizing of dom0 memory and not a memory leak in Xen networking.  If this is the case my config with dom0_mem == dom0-min-mem should eliminate the problem completely.

I'll reply again in a week and let you know what happens.

Thanks for the help,
Scott Moe

On 1/11/07, Scott Moe < smoe868@xxxxxxxxx> wrote:

I have had servers run Xen 2 without rebooting Dom0 for most of a year.

I am working now on a very similar machine with Xen 3.03 and Debian etch.

My network setup is slightly customized. I have 3 IP's and use network-route in xend-config.sxp. I specify vif-route as the vif script in the DomU config for 2 of my VM's.

I also create a bridge in /etc/network/interfaces. I have two other VM's that only interface to this bridge and the VM's with their own IP's have a second vif on the bridge. I specify the vif-bridge script in vif config for these interfaces.

Everything boots and runs great, for several hours. Yesterday, for example, the machine was rebooted in the morning. It ran for 11 hours without errors, then the kern.log started to fill up with this message:
xen-net: memory squeeze in netback driver
This went on for 13 hours at a rate of something like 5 to 10 messages per second. Then the log shows each vif on the bridge entering disabled state. The vif's with dedicated IP's were not mentioned in the log, but this morning only the dom0 ip was responsive. When I ssh into dom0 and try to ping the IP's routed to VM's I see no route to host. I looked at route and everything was listed correctly.

I hope someone has seen a similar problem and can give me some insite. My experience is limited but to me this smells like a memory leak. Perhaps there are updates that will fix this problem but have not made it into the Debian etch packages.

Thanks,
Scott Moe

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