Slow xennet, occasionally

[marcotte%panix.com@localhost (Brian Marcotte)]

I'm occasionally seeing a slow xennet is domU:


  Throughput is perhaps 20% of normal, and pings are about 5 times
  higher.

  When the problem occurs, it's always present from boot.

  When the first xennet is slow at boot time, I can add a second xennet
  and it will usually be fast.

  Usually one reboot will fix the problem.

  I've seen this on NetBSD 6 and 7.

  Disk I/O and CPU are normal

  dom0 is Xen 4.3.3 and Linux 3.14 - no problem seen in dom0


Has anyone else seen this? I don't even know where to begin with this
one. I have not been able to determine any pattern.

Thanks.

--
- Brian