[Beowulf] Has DDR IB gone the way of the Dodo?
hahn at mcmaster.ca
Fri Oct 3 07:00:05 PDT 2008
>> Has DDR IB gone the way of the dodo bird and been supplanted by QDR?
> I don't think front side busses are fast enough for QDR yet.
qdr would be 40 Gb (raw data rate, right? so 4 GB/s before any sort
of packet overhead, etc.) I don't really see why that's a problem -
even a memory-constrained current-gen Intel box has about twice
that much memory bandwidth available. AMD or next-gen-Intel will
be even less constrained.
otoh, I rarely see workloads that are clearly net-bw-limited even
on 4-core myrinet 2g machines - and that's only about 250 MB/s.
regards, mark hahn.
More information about the Beowulf