IN: Numeric threshold for performing linked-chunk I/O
H5P_SET_DXPL_MPIO_CHUNK_OPT_NUM sets a numeric threshold for the use of linked-chunk I/O.
The library will calculate the average number of chunks selected by each process when doing collective access with chunked storage. If the number is greater than the threshold set in num_chunk_per_proc, the library will use linked-chunk I/O; otherwise, a separate I/O process will be invoked for each chunk (multi-chunk I/O).
Returns a non-negative value if successful. Otherwise returns a negative value.