[Mpi-comments] MPI_Create_directory

[William Gropp]

Are we assuming a POSIX filesystem (a bad idea in my opinion)? Are we assuming a more restricted set of file system structure operations, along with weaker consistency semantics (matching the MPI-IO approach rather than POSIX)?

Bill

William Gropp
Director and Chief Scientist, NCSA
Thomas M. Siebel Chair in Computer Science
University of Illinois Urbana-Champaign






> On Jan 7, 2019, at 8:28 AM, Axel Huebl via mpi-comments <mpi-comments at lists.mpi-forum.org> wrote:
> 
> Dear MPI-Forum,
> 
> 
> should we extend the MPI-I/O interfaces for directory operations? Especially a "mkdir -p" equivalent could be useful.
> 
> In many scientific apps that create output at scale, an output structure needs to be created on demand.
> 
> One can of course decide to do so with e.g. Linux `mkdir` but this can be tricky:
> 
> If all ranks do it, one will race the others and it's unnecessary expensive in terms of operations.
> 
> If a "root" rank does it, there is no guarantee that e.g. a MPI_Barrier which syncs the "MPI-World" will also cause the "filesystem-world" to be up-to-date. For example a mkdir on a slow NFS local node has bot yet propagated to the other compute nodes.
> 
> Comments, feedback and overlooked already existing solutions welcome!
> 
> 
> Best regards,
> Axel Huebl
> -- 
> 
> Axel Huebl
> Phone: +49 351 260 3582
> Institute of Radiation Physics
> http://www.hzdr.de/crp
> Helmholtz-Zentrum Dresden - Rossendorf (HZDR)
> Bautzner Landstr. 400 | 01328 Dresden | Germany
> Board of Directors:
> Prof. Dr. Dr. h. c. Roland Sauerbrey, Dr. Ulrich Breuer
> Company Registration Number VR 1693, Amtsgericht Dresden
> _______________________________________________
> mpi-comments mailing list
> mpi-comments at lists.mpi-forum.org
> https://lists.mpi-forum.org/mailman/listinfo/mpi-comments

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mpi-forum.org/pipermail/mpi-comments/attachments/20190107/4a96c929/attachment.html>