I/O performance is a significant bottleneck for earth system simulations, especially at higher resolutions and/or with high frequency I/O. All E3SM model components use the SCORPIO library for reading input data and writing output to the file system. The library caches and rearranges data among the model compute processes to improve I/O throughput of low level libraries like PnetCDF, NetCDF, HDF5 and ADIOS. We present the recent feature enhancements in the library and discuss I/O performance of E3SM high and ultra high simulations on the latest supercomputers. We also describe upcoming enhancements in the library that will be of interest to all E3SM users.
