[lxc-devel] LXC/Cgroup cpu.shares issue?

[Yang, Andy]

Hi all,

I try to use LXC to control my CPU-hogging test application's CPU usage 
and I find there is an issue:

I run two processes of the test application at same time (one is running 
inside LXC container, another is running without container), and I find 
the running inside container's process will consume much more CPU 
resource than another one, no matter how many 'cpu.shares' setting.

Any one know this issue? I haven't used 'cpu.cfs_quota_us' to control.

Test example:
'containertestapplication' and 'containertestapplication2' are same test 
application. But 'containertestapplication' is running in a LXC 
container and is consuming 85.9% CPU while 'containertestapplication2' 
is running without container and consuming only 9.1% CPU.
---

CPU0:  0.9% usr  1.1% sys 97.8% nic  0.0% idle  0.0% io  0.0% irq  0.0% sirq
Load average: 3.95 3.89 3.00 3/138 264
   PID  PPID USER     STAT   VSZ %VSZ %CPU COMMAND
   244   240 1035     R N  13344  2.1 85.9 /usr/applications/containertestapplication/containertestapplication
   247   124 1036     R N  13344  2.1  9.1 /usr/applications/containertestapplication2/containertestapplication2
...
...
---


Appreciate you feedback. Thnaks