Re: Pi flavour?
Yes, the Ethernet and 4 port USB hub all go via a single USB port into the SoC. Yes, it is a bottleneck, no it hasn't really stopped a lot of sales, because in general people are not too worried about it. Those who really need the throughput get alternative devices and live with the less than useful support.
As for whether this is a toy, I'd suggest that if Los Alomos National Lab though it was a good idea to make one, then it's not really a toy. After all, it's not like the Pi is the new kid on the block with an unexpected design that will catch them unawares.
This is a project for testing code in an environment similar to the real HPC's, so you don't take up valuable compute time ironing out the kinks. It gives you 750 * 4 core A53 devices running at 1.2GHz, with slow interconnects and only 1GB RAM per node, buts costs less than $35k or so (my figures, not sure of final cost, assuming $35/Pi ex VAT plus costs for the Bitscope racks)
Biting the hand that feeds IT
