[Beowulf] Re:Fortran Array size question

[David Mathog]

Prentice Bisbal <prentice at ias.edu> wrote:

> Question: What is the maximum number of elements you can have in a
> double-precision array in Fortran? I have someone creating a
> 4-dimensional double-precision array. When they increase the dimenions
> of the array to ~200 million elements, they get this error:
> 
> compilation aborted (code 1).

The two things that come immediately to mind are:

1.  The compiler ran out of memory.  (In addition to the size of the
memory in the machine, check ulimit.)

2.  The compiler is trying to build the program with 32 bit pointers and
it cannot address this array, or perhaps all memory accessed, with a
pointer of that size.  If that is the issue using 64 bit pointers should
solve the problem, but I can't tell you what compiler switches are
needed to do this.

Regards,

David Mathog
mathog at caltech.edu
Manager, Sequence Analysis Facility, Biology Division, Caltech