[ovs-discuss] QoS

[Ben Pfaff]

You could use a controller.

You are probably wasting your effort, though, because the QoS in use
probably does not do anything if the link is not congested.

On Sat, May 14, 2016 at 12:22:21PM -0700, Aravind Ganesan wrote:
> Ben,
> Thanks for your reply.
> So is there a possible indirect method to achieve it?
> In my case too the QoS need not do anything when there is no congestion,
> but I want to invoke them when there is congestion. I am able to get the
> network statistics, but am unable to proceed after that.
> It would be helpful if you could suggest something.
> 
> Thanks
> 
> On Sat, May 14, 2016 at 11:51 AM, Ben Pfaff <blp at ovn.org> wrote:
> 
> > On Fri, May 13, 2016 at 11:19:19PM -0700, Aravind Ganesan wrote:
> > > I have created QoS classes, and am able to separate the traffic based on
> > > source address.
> > > What I want to do now is enable QoS classes only when link is congested.
> > > For example, if there are 3 hosts, h1, h2, h3, connected by single switch
> > > s1.  Suppose h1 is sending file to h3. Simultaneously h2 wants to send
> > file
> > > to h3. I measure the bandwidth of s1->h3. If it is less than say 100
> > Mbps,
> > > I invoke QoS class and give priority to packets from h2.
> > > Is it possible to do this?
> >
> > OVS can't do that directly, but there's not much value in it anyway
> > because most QoS strategies don't do anything if the link is not
> > congested.
> >