Benchmark programs

  • IOR ( has a 'driver' for PnetCDF
  • The  FLASH I/O kernel, developed at the FLASH center of University of Chicago, measure severals write-only workloads. Starting from 1.4.0 release, PnetCDF distribution includes the FLASH-IO kernel that uses PnetCDF APIs.
  • BTIO, S3D-IO, and GCRM-IO that use PnetCDF method are available  here.

Notes and suggestions

Be mindful of benchmarks which write large contiguous chunks of data. While interesting, it might not be what a scientific application using PnetCDF would actually do.

Older versions of IOR triggered a performance bug on some Lustre file systems. Sometimes slow write performance on Lustre can be fixed by disabling the "data sieving" optimization. See HintsForPnetcdf for more information.