unipost for parallel netcdf

Dear colleagues,
I use wrf-nmm v4.3 on the cluster, it produces wrf_output files in parallel netcdf format. I also have UPP v3.1.1 for the model outputs postprocessing. The problem is in the very low speed of execution of unipost.exe file (2.5-3 times slower than with ordinary netcdf)!
Can anyone help me to speed up this process?

The parallel netcdf capability has only been implemented for FV3 model cores in the UPP, so unfortunately other models (e.g. wrf-nmm) will not benefit from increased execution speeds of pnetcdf format.