[Lxc-users] seeing a network pause when starting and stopping LXCs - how do I stop this?

[Joseph Heck]

I've been seeing a pause in the whole networking stack when starting
and stopping LXC - it seems to be somewhat intermittent, but happens
reasonably consistently the first time I start up the LXC.

I'm using ubuntu 11.10, which is using LXC 0.7.5

I'm starting the container with lxc-start -d -n $CONTAINERNAME

The configuration file:
-----
lxc.network.type = veth
lxc.network.flags = up
lxc.network.link = br-v10

lxc.utsname = mysql

lxc.tty = 4
lxc.pts = 1024
lxc.rootfs = /var/lib/lxc/mysql/rootfs
lxc.mount  = /var/lib/lxc/mysql/fstab
lxc.arch = amd64

lxc.cgroup.devices.deny = a
# /dev/null and zero
lxc.cgroup.devices.allow = c 1:3 rwm
lxc.cgroup.devices.allow = c 1:5 rwm
# consoles
lxc.cgroup.devices.allow = c 5:1 rwm
lxc.cgroup.devices.allow = c 5:0 rwm
#lxc.cgroup.devices.allow = c 4:0 rwm
#lxc.cgroup.devices.allow = c 4:1 rwm
# /dev/{,u}random
lxc.cgroup.devices.allow = c 1:9 rwm
lxc.cgroup.devices.allow = c 1:8 rwm
lxc.cgroup.devices.allow = c 136:* rwm
lxc.cgroup.devices.allow = c 5:2 rwm
# rtc
lxc.cgroup.devices.allow = c 254:0 rwm
#fuse
lxc.cgroup.devices.allow = c 10:229 rwm
# loopback
lxc.cgroup.devices.allow = b 7:* rwm
-----

Any ideas why the host system would appear to totally pause networking
(ping doesn't respond, etc) for up to ~15 seconds when you're starting
or stopping a container?
I'm assuming it is some configuration mistake I've made, but I'm at a
loss to find out why it's happening.

-joe