[ovs-discuss] Can Openvswitch support QoS for linux Containers

[Jesse Gross]

On Sun, Feb 17, 2013 at 12:18 AM, Ryan Young <ryanyoung.soloy at gmail.com> wrote:
> hi all,
> I setup a topology with two lxc containers on a host and apply OVS as the
> network module. In my test I cannot apply QoS policies to the two
> containers( for example,  ovs-vsctl set Interface pbond0
> ingress_policing_rate=100000). It is said that OVS use linux TC for the
> ratelimit function ( the module is compiled in the kernel), and LXC
> containers does not have its own network stack, is that the reason the QoS
> did not take affect?

LXC still uses the standard Linux networking stack, so it's unlikely
to be the issue.  Please see this entry in the FAQ:

Q: I configured QoS, correctly, but my measurements show that it isn't
   working as well as I expect.

A: With the Linux kernel, the Open vSwitch implementation of QoS has
   two aspects:

       - Open vSwitch configures a subset of Linux kernel QoS
         features, according to what is in OVSDB.  It is possible that
         this code has bugs.  If you believe that this is so, then you
         can configure the Linux traffic control (QoS) stack directly
         with the "tc" program.  If you get better results that way,
         you can send a detailed bug report to bugs at openvswitch.org.

         It is certain that Open vSwitch cannot configure every Linux
         kernel QoS feature.  If you need some feature that OVS cannot
         configure, then you can also use "tc" directly (or add that
         feature to OVS).

       - The Open vSwitch implementation of OpenFlow allows flows to
         be directed to particular queues.  This is pretty simple and
         unlikely to have serious bugs at this point.

   However, most problems with QoS on Linux are not bugs in Open
   vSwitch at all.  They tend to be either configuration errors
   (please see the earlier questions in this section) or issues with
   the traffic control (QoS) stack in Linux.  The Open vSwitch
   developers are not experts on Linux traffic control.  We suggest
   that, if you believe you are encountering a problem with Linux
   traffic control, that you consult the tc manpages (e.g. tc(8),
   tc-htb(8), tc-hfsc(8)), web resources (e.g. http://lartc.org/), or
   mailing lists (e.g. http://vger.kernel.org/vger-lists.html#netdev).