Re: [RFC] TCP congestion schedulers

[Stephen Hemminger <shemminger@xxxxxxxx>]

On 29 Mar 2005 17:25:38 +0200
Andi Kleen <ak@xxxxxx> wrote:

> > Running on 2 Cpu Opteron using netperf loopback mode shows that the change 
> > is
> > very small when averaged over 10 runs. Overall there is 
> > a .28% decrease in CPU usage and a .96% loss in throughput.  But both those
> > values are less than twice standard deviation which was .4% for the CPU 
> > measurements
> > and .8% for the performance measurements.  I can't see it as a worth
> > bothering unless there is some big money benchmark on the line, in which 
> > case
> > it would make more sense to look at other optimizations of the loopback
> > path.
> 
> Opteron has no problems with indirect calls, IA64 seems to be different
> though.

Getting IA64 setup today, to check.

> But when you see noticeable differences even on a Opteron I find
> it somewhat worrying.

The difference was so tiny that it is in the noise of the measurements.