Pallas Benchmarck results for Miniwulf

Update: Now that Mini has four nodes, I ran the Pallas benchmark again. The results are available here. This is for four nodes, running MPICH on a 10bT hub.

I ran Miniwulf in four configurations to gather benchmark data:
Since the NICs in miniwulf's nodes are 10bT running half duplex, the cluster couldn't take full advantage of the fast ethernet switch. None the less, use of the switch did cut down on collisions, but added some latency at lower bandwidths. Here are some of the benchmark results in graphical form:









The interesting thing here is the step discontinuity at or around 8K bytes. This shows up in all the benchmark tests. Below this LAM-MPI running on a hub seems the fastest, and after MPICH on the switch is the clear winner. I'm guessing the cause of this is that less than 8K may be able to fit in a single packet, and the hub communicates this the fastest. Above it, and collisions become a problem. Here the switch helps releive the bottle-neck to a certain degree.

I should also note that all these results were from two nodes running the tests with a third waiting in the barrier state. For some reason, LAM-MPI experienced memory errors trying to run the tests on three or more nodes at once.

For those interested, the raw output of the benchmark runs is here:

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