On Aug 13, 2008, at 7:06 PM, Yvan Fournier wrote:
I seem to have encountered a bug in MPI-IO, in which
MPI_File_get_position_shared hangs when called by multiple processes
in
a communicator. It can be illustrated by the following simple test
case,
in which a file is simply created with C IO, and opened with MPI-IO.
(defining or undefining MY_MPI_IO_BUG on line 5 enables/disables the
bug). From the MPI2 documentation, It seems that all processes
should be
able to call MPI_File_get_position_shared, but if more than one
process
uses it, it fails. Setting the shared pointer helps, but this should
not
be necessary, and the code still hangs (in more complete code, after
writing data).
I encounter the same problem with Open MPI 1.2.6 and MPICH2 1.0.7, so
I may have misread the documentation, but I suspect a ROMIO bug.
Bummer. :-(
It would be best to report this directly to the ROMIO maintainers via romio-ma...@mcs.anl.gov
. They lurk on this list, but they may not be paying attention to
every mail.
If you wouldn't mind, please CC me on the mail to romio-maint. Thanks!
--
Jeff Squyres
Cisco Systems
