50Msps performance

I thought I’d try a simple 50Msps flow-graph with the latest Gnu Radio
to see how well it now works.

I’ve attached it. As you can see, it doesn’t do very much. A UHD
source, a single multiply, then a null sink.

On a 6-core machine running at 3.2GHz, it gets overruns, nearly
continuously. This isn’t noticeably different from prior to the
latest performance changes in Gnu Radio, except that the overruns
happen at perhaps a somewhat lower rate. A single
data point in a very complicated space, but I think processing very
high sample rates in Gnu Radio is going to be tough.
Although I know that the CASPER folks have done this in the past, as
have the GMRT folks in India. But they don’t
use Gnu Radio, but rather highly-customized stuff that doesn’t
necessarily do much processing on the samples.

This was on a AMD Phenom II X6 1090T. Not the highest performance
machine on the planet, but not the worst, either.