Lxc-ls , lxc-top stops responding now and then

LXC
1

Hello, i am using LXC 3.0.0 and LXCFS 3.0.0 compiled from sources on an Ubuntu 16 server

Distributor ID: Ubuntu
Description: Ubuntu 16.04.3 LTS
Release: 16.04
Codename: xenial

lxc-ls --version output is 3.0.0

i have 4 containers working perfectly, the problem is that when i execute lxc-ls , lxc-top from my LXC server
sometimes these 2 commands stop responding and produce no output.

i still can access my containers with ssh from another computer.

Anybody has the same problem? is there any solution?

I would appreciate any help.

Carlos.

2

Can you paste the output of dmesg or sent it to christian.brauner [at] ubuntu dot com?

3

Hi
I cannot reproduce the error situation that leads the commands lxc-fs and/or lxc-top to stop responding
but of course i could send you the output of dmesg.

Is your mail christian.brauner.ubuntu.com?

4

Yeah, but obviously with an @ jammed in between my last name and ubuntu.com instead of a .

5

Ok, so what you send me looks benign. If you see that issue again, please provide record the output of:

cat /proc/<container-init-pid>/stack

and try to kill it with lxc-stop -k <container-name>.

6

Hi
Ok, i will do that next time i have this problem.

In the meantime could you confirm if i am correctly limiting the resources of my container?

in its configuration file i put the following lines:

lxc.cgroup.cpuset.cpus=2,3,4,5
lxc.cgroup.cpu.shares=256
lxc.cgroup.blkio.weight=500
lxc.cgroup.memory.soft_limit_in_bytes=268435456
lxc.cgroup.memory.limit_in_bytes=10737418240

the fact is that it seems to work but i am not sure if i am doing it correctly as i have seen something about lxc.prlimit.[limit name] in here: https://linuxcontainers.org/lxc/manpages/man5/lxc.container.conf.5.html

I would appreciate any help.

Carlos.

7

Looks good. lxc.prlimit.[limit name] is another set of resource restrictions you can apply, yes. You should check whether it makes sense for your use-case and what you’d like to limit though.