Tuning collective I/O strategies for GPFS and Lustre
ROMIO’s strength lies in how it hides the details of the underlying file system from the end-user. MPI_File_open looks the same if you are writing to PVFS or GPFS, even though both systems have very different lower-level interfaces. When it comes to the venerable but powerful two-phase collective I/O optimization, those file system quirks matter …