[Beowulf] SC|05: will 10Ge beat IB?

[Greg Lindahl]

> Is Myrinet 10G latency higher than Quadrics?  Myricom quoted 1.8 microseconds
> at SC05, but I forgot what Quadrics is these days.  The difference between
> Infinipath and other PCI-Express solutions is the bus.  If/when Myricom or
> Quadrics provide HT support, their latency will be near Infinipath.

Craig,

Our chip's architecture is completely different, so no, it's not just
the bus. However, you are correct to note that other features are
going to be more important, because they already are: 0-byte latency
and infinite-size bandwidth aren't great predictors of application
performance. And our current performance is driven more by these other
features than just 0-byte latency. This pains our marketing people to
no end, but such is life.

> If/when Pathscale releases a PCI-E card, its latency will be worse,
> and similar to the others.

It would be worse than our HT card, yes. But we don't think it would
be similar to the others. I guess you'll have to wait and find out!

-- greg
(employed by, not speaking for, yadda yadda yadda.)