[lxc-users] lxc-start hanging

[Mahmood]

Recently, we have noticed a spike of lxc-start hanging in our fleet of
short-lived containers.  After a machine successfully starting and
stopping short-lived containers for awhile, a `lxc-start` hangs along
with all subsequent lxc-start operations for new containers.  The host
looks healthy otherwise for other applications, and lxc-stop succeeds
for the remaining containers.

The lxc logs and strace can be found at
https://gist.github.com/notnoopci/56cc26e3573745c65a73 .  It doesn't
seem correlated with a change in lxc/cgroup/kernel versions, and I
didn't notice an odd behavior of the containers running immediately
prior to the machine getting wedged.  I also tried disabling apparmor
profile and using (un-)privileged containers without any luck.

Any hints on how to debug the problem?  The hosts are running with
Ubuntu LTS 14.04 with kernel 3.14.19-031419-generic  and lxc version
1.0.5.

- Mahmood