in which files that were accessed by all ranks are collapsed into a single
cumulative file record at rank 0. This option retains more per-process
information at the expense of creating larger log files.
* DARSHAN_LOGPATH: specifies the path to write Darshan log files to. Note that this directory needs to be formatted using the darshan-mk-log-dirs script.
* DARSHAN_LOGFILE: specifies the path (directory + Darshan log file name) to write the output Darshan log to. This overrides the default Darshan behavior of automatically generating a log file name and adding to a log file directory formatted using darshan-mk-log-dirs script.
