[Beowulf] ever heard of ScaleMP?

[Mark Hahn]

> Flextronics was showing a small cluster where they had 4 boxes connected
> by IB and within each box they had 4 systems connected by IB. They were
> running ScaleMP on it. They had a graph of running Stream on top of the
> system. They were plotting bandwidth vs. number of cores and it was fairly
> linear (I didn't get a close look at it).

but stream is embarassingly parallel, so even if their interconnect was 
wet string, it should scale perfectly with number of nodes.  (well, 
start and end-of-loop synchronization probably doesn't work well with 
wet string, but that just means you crank up the array size ;)

does anyone know how the coherency actually works?  without a full-fledged
memory proxy (as SGI has in their NUMAlink machines, or as in the Newisys
Horus), it seems like this approach is going to spend a lot of time twiddling
the MMU and taking page faults.