[Lustre-discuss] Infiniband question...

[Corey Kovacs]

I am in the early planning stages of putting together a lustre system
and when I look at IB speeds it seems most if not all the 40Gb IB
cards are running over PCIe with 8 lanes. If PCIe lanes are good for
about 200MB/s that means I can only get 1600MB's tops from one of
these cards, but 40Gb xlates to around 4GB/s. Am I reasoning this
correctly or is have the potential of the card wasted?

I can see using 40Gb switches to get the backplane speed and reduce
contention on the switch but what are people using on the hosts?


Corey