Hi, A question more for the mpich3 developers: If I were to implement an ADIO interface to a file system in mpich3, would I have to implement optimizations like two-phase I/O myself or are these optimizations implemented outside ADIO, independently of the file system? Thanks, Matthieu Dorier PhD student at ENS Cachan Brittany and IRISA http://people.irisa.fr/Matthieu.Dorier