[MITgcm-support] Better than expected HPC Scaling

[Edward Doddridge]

Hi MITgcmers,

As part of an HPC bid I need to provide some scaling information for MITgcm on their cluster. The test configuration is a reentrant channel 600x800x50 grid points, using just the ocean component and some idealised forcing fields. As I increased the core count between 48 and 384 the model scaled better than the theoretical scaling (see attached figure). I’m not complaining that it ran faster, but I was surprised. Any thoughts about what would cause this sort of behaviour? I wondered if it might be something to do with the tiles not fitting in the cache for the low core count simulations. The bid might be more convincing if I can give a plausible explanation for why the model scales better than ideal.

Cheers,
Ed



Edward Doddridge
Research Associate and Theme Leader
Australian Antarctic Program Partnership (AAPP)
Institute for Marine and Antarctic Studies (IMAS)
University of Tasmania (UTAS)

doddridge.me


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