  We report optimization work made in support of the development of a realtime
Superfacility workflow between DIII-D and NERSC. At DIII-D, the ion properties
measured by charge exchange recombination (CER) spectroscopy are required
inputs for a Superfacility realtime workflow that computes the full plasma
kinetic equilibrium. In this workflow, minutes matter since the results must be
ready during the brief 10-15 minute pause between plasma discharges. Prior to
this work, a sample CERFIT analysis took approximately 15 minutes. Because the
problem consists of many calculations that can be done independently, we were
able to restructure the CERFIT code to leverage this parallelism with Slurm job
arrays. We reduced the runtime to approximately 51 seconds -- a speedup of
roughly 20x, saving valuable time for both the scientists interested in the CER
results and also for the larger equilibrium reconstruction workflow.
