e. Scaling Graphs

We tested the performance and scaling of MPAS in collaboration with DTN using the Hurricane Laura, a deadly and destructive Category 4 hurricane that made landfall in Louisiana on August 29, 2020. The model resolution is 15km-Global with refined 3-km grid/mesh over the Gulf of Mexico. As shown below, we ran scale-up tests across 32 to 128 hpc6a.48xlarge instances, measuring total wall-clock times (compute + file I/O) over a 6hr forecast. Performance scales linearly as we scaled out to 128 instances, with a minimum simulation cost when using 64 instances.

In the following charts we use two metrics, Simulation Speed and Cost per Simulation, we define those as follows:

  • Simulation Speed = forecast time (sec) / Wall-clock Time (sec)
  • Cost Per Simulation ($) = Wall-clock Time * EC2 On-Demand Compute Cost (us-east-2 pricing) * # instances

MPAS Scaling Per-Node