CAM Scalability on Janus
For further information about this test, please contact Richard Urata
This was just a simple test using my 2x2.5 Mars-CAM model.
Model run parameters were 10 model days, at timesteps of 600s (comes out to 1480 steps), up to 10 nodes, using npr_yz=24,x,x,24, Mars-RT calcs on the hour (so every 6 steps), daily history write-outs.
The test shows that 8 nodes (for a total of 96 processors) seems to be the "sweet spot" on this computer. There is an increase in computation speed going from 8 nodes to 10 nodes, and I did not test 9 nodes. Janus allows up to 1024 cores on the janus-normal queue (~85 nodes), so there is no reason not to always use 8 nodes.