I've been testing the new Intel MPI 3.2.2 release which has support for Panasas' PanFS. I've checked out an evaluation copy of the library, but am running into what I believe is a bug with the use of layout hints to a shared file. For the case of more than 1 thread accessing a file, (N-to-1), this fails as each thread is trying to perform an ioctl call to the file and returning:
"ADIOI_PANFS_OPEN: I/O Error doing ioctl on parent directory to create PanFS file using ioctl: File exists."
I believe that the correct behavior is that one thread will call the CREATE_FILE ioctl on the directory to create the file. If all the threads call the ioctl, however, its a race and only one thread will succeed.
I believe the code should do something like:
If (rank == 0)
Instead, all threads attempt the ioctl(CREATE_FILE), with only one succeeding and the rest failing.
If it would help, I can provide a test case for this behavior.