InfiniBand switch maker Voltaire announced this morning that it would be crossing the high-speed protocol divide and will later this year launch a set of converged switches based on the 10 Gigabit Ethernet protocol. While the current InfiniBand technologies offer 20 Gb/sec (dual data rate) and 40 Gb/sec (quad data rate) …
1 Dimensional Thinking Again
Latency. Low end-to-end latency is just as important as bandwidth. That is a major reason that early compute clusters discarded ethernet. You can provide a channel a mile wide in terms of signalling rate and still not achieve application throughput if the latency is too high.
Infiniband vs GigE
GigE usually uses TCP/IP - and this protocol, while tremendously redundant & wonderful for convergence, is not terribly efficient at higher capacities.
Infiniband is a beautiful thing for high performance & clustered databases. Clustering memory caches between nodes requires high bandwidth and low latency - otherwise performance & scalability is limited.
I would have been interested to see a comparison between Voltaire and SUN as far as Infiniband switches in terms of capacity, size, and latency on a flattened network... instead of only Cisco.