On Titan, the working parallel compiler is currently mpif77, which is performed by a "make mpich" with the standard Makefile (has to be called on the dn?? nodes and not on dm01!).

Binary problem on Titan:

The underlying g77 is under version 4.2 and thus the record-marker in f77 unformatted binary-files is of 8 byte length if compiled on 64Bit machines like Titan. This is not according to the standard (4 byte marker) and the output-binaries can not be read if compiled on 32Bit machines. It should be noted that IDL does stick to the standard as well and thus can't read the files. This faulty behaviour of g77 was altered with version 4.2 of the gcc:
http://www.gnu.org/software/gcc/gcc-4.2/changes.html ("->Fortran")

Solutions:

• A possible solution to this problem is to simply compile the data analysis tools with g77 on Titan as it expects the record marker to be of 8 byte length.

• If for example IDL has to be used for data analysis, the attached converter tool can be of help: http://nb6mpi.pbwiki.com/f/binconv.f it creates a file called conv.< filename> with the standard 4 byte marker (works, but no guarantee...).

 Create your own educational wiki!Support CommunityPublic, not yet premium Privacy Policy RSS