features – ROMIO

Non-blocking collective I/O

May 6, 2015 by Latham, Robert J.

The MPI standard defines non-blocking communication. It also defines non-blocking (independent) I/O. When it comes to collective I/O, the choices are blocking I/O or the little-developed and little-used “split collectives”. The HDF Group pushed to add true non-blocking collective I/O to the MPI standard. MPI-3.1 finally incorporates this feature. The use cases are motivated by …

Deferred Open

August 5, 2003 by Latham, Robert J.

When I came to Argonne in 2002, my second project was to implement “deferred open”, where we would skip opening the file if certain hints were given. We never got around to writing a paper about this optimization, though. There’s a brief mention in the ROMIO users guide , but it wouldn’t hurt to have …