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WRF-Hydro model code
https://ral.ucar.edu/projects/wrf_hydro
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Model MPI enhancements #711

Closed rcabell closed 1 year ago

rcabell commented 1 year ago

TYPE: enchantment

KEYWORDS: MPI, Cray, Derecho

SOURCE: Ryan @NCAR

DESCRIPTION OF CHANGES:

A number of MPI point-to-point calls in mpp_land.F were changed to use Collective communications. This improves performance on the new NCAR Cray system "Derecho".

ISSUE: Fixes #710

TESTS CONDUCTED:

National Water Model v3.0 CONUS Analysis and Assimilation configuration

rcabell commented 1 year ago

I removed additional mpp_land_sync() calls from the IO routines, and testing results over CONUS (on Derecho) were the same. Some non-bit-identical results but down in the noise, near or at floating-point epsilon.