The ABINIT Users Mailing List ( CLOSED )

[Kristopher Andersen <andersen@yclept.ucdavis.edu>]

On Tue, 4 Nov 2003, Jan Gryko wrote:
> I am using sequential version of ABINIT which is restricted to 2 GB
> of memory because 2**31-1 limit for 32 bit processors. I am
> wondering if it is possible to run abinit jobs that require more
> than 2 GB on a cluster of Intel Pentium PC?

I don't have any real expertise in either hardware or compilers, but
I've hit the IFC memory ceiling as well. My understanding is that even
though linux can see and access the memory, IFC can't allocate arrays
bigger than 2GB. Interestingly, the analogous memory limit for the
Portland Group compiler is closer to 3GB. If you're in the middle (I
was), you may have luck using the PGI compiled executable from the
ABINIT web page. Otherwise, I think the only solution is to move to a
64 bit architecture.

If you're interested I can send you a document I've come across
prepared by the computational support staff at LLNL with more
information about the memory constraints of the two compilers on ia32
architectures.

-- 
Kristopher Andersen               http://yclept.ucdavis.edu/~andersen
Department of Physics                    andersen@physics.ucdavis.edu
University of California at Davis                   +1 (530) 752-0446