Domain 0 crashes when booting a single VM with a large # of VIFs
If I create a single VM, one that has 123 VIFs (by adding 123 VIF entries in my VM configuration file - all VIFs go to the same bridge), my machine crashes while XEN is trying to boot my VM. XEN crashes at the point of the boot where it is initialing the ethernet interface (the machine reboots immediately). If the VM has 122 VIFs, it boots up and works fine (I use ifconfig to verify the VIFs are indeed present - all 122 are accounted for).
Now, if I create 61 VMs, each with only 1 VIF, that works fine. As soon as I try to boot the 62nd VM, I hit the same problem (crash and reboot). It appears that the magic number is 123 for the # of VIFs -it also looks like XEN is creating a phantom VIF for each VM that is created. So in the case of 61 VMs with 1 VIF each, I have 122 VIFs. As soon as I go above this number, XEN dies.
Does anyone know why this happens - a bug in XEN or is this some sort of XEN limitation?
This is occurring on Xen 2.0.6 / XenLinux 2.6.11, AMD opteron. I also hit this same problem with XEN 2.0.1.