hdf5_ep

 *

 * mpi_rank:    MPI rank of this process within mpi_comm.

 *

 * mpi_size:    Number of processes in mpi_comm.

 *

 * write_permitted:  Boolean flag used to control whether the cache

 *      is permitted to write to file.

 *

 * dirty_bytes_threshold: Integer field containing the dirty bytes

 *      exceeds this value, the metadata cache on process 0

 *      broadcasts a list of the entries it has flushed since

 *      the last broadcast (or since the beginning of execution)

 *      and which are currently clean (if they are still in the

 *      cache)

 *

 *      Similarly, metadata caches on processes other than process

 *      0 will attempt to receive a list of clean entries whenever

 *      the threshold is exceeded.

 *