[lxc-users] Enabling real time support in containers

[Peter Steele]

We have a need to create real time threads in some of our processes and 
I've been unable to configure an LXC container to support this. One 
reference I came across was to set a container's real time bandwidth via 
the lxc.cgroup.cpu.rt_runtime_us parameter in its config file:

lxc.utsname = test01
lxc.include = /var/lib/lxc/centos.conf
lxc.network.veth.pair = test01
lxc.network.hwaddr = fe:d6:e8:e2:fa:db
xc.rootfs = /var/lib/lxc/test01/rootfs
lxc.rootfs.backend = dir
lxc.cgroup.cpuset.cpus = 0,1
lxc.cgroup.memory.limit_in_bytes = 2097152000
lxc.cgroup.memory.memsw.limit_in_bytes = 3170893824
lxc.cgroup.cpu.rt_runtime_us = 475000

This container starts up fine if lxc.cgroup.cpu.rt_runtime_us is 0 
(zero). Anything other than 0 is rejected, which means real time threads 
cannot be created in this container.

What am I missing to get this to work? I am using lxc version 2.0.6 
under CentOS 7.2. The container is being created using a custom CentOS 
7.2 image.

Thanks for the help.

Peter Steele