Re: [Bloat] [Codel] better testing, linux 3.6.1, cerowrt credits, other stuff

[Luigi Rizzo <rizzo@iet.unipi.it>]

On Wed, Oct 10, 2012 at 04:29:11PM -0700, Stephen Hemminger wrote:
> On Wed, 10 Oct 2012 19:27:11 -0400
> Michael Richardson <mcr@sandelman.ca> wrote:
> 
> > 
> >     >> But: It became obvious fast that long RTT tests were needed,
> >     >> which I've been trying to establish the infrastructure to do
> > 
> >     toke> I assume that by "infrastructure" you mean "(netperf) servers
> >     toke> far away"? What would be needed for a test server in terms of
> >     toke> resources (bandwidth and otherwise)? I could try and persuade
> >     toke> my university to let me setup a test server on their network
> >     toke> (which is in Denmark)...
> > 
> > I interpret the question to mean networks where is there significant
> > actual delay along them.  I seem to recall that there are some ways to
> > do this Linux machines, but most commercial test equipment can simulate
> > things, including dropping packets.
> > I think, however, that we do not want/need and packets dropped, as then
> > the bandwidth constraint would not be in the device under test.
> 
> netem can do all the stuff commercial gear can.
> In fact, it is used by one of the commercial products!

similarly you can use ipfw+dummynet, it has been running on
Linux and a variety of other OS for a long time, see

http://info.iet.unipi.it/~luigi/dummynet/

	cheers
	luigi