NEC-LIST: NEC Execution Times Under Windows

We are running NEC4.1 on a PC and are surprised about the execution
time results. Using the same executable compiled under Lahey F77
-EM/32, we are seeing much less of an improvement than we expected.
The execution times are only a factor of ~3 faster on a 200 MHz
Pentium MMX With 128 MB of SDRAM (10 ns) in DOS box on Win 95 OSR2
than on a 90 MHz Pentium with 16 MB of RAM (70 ns) in DOS box on Win
3.1. We expected an improvement closer to 10 times faster.

The 3 times improvement factor is consistent on smaller ("in core")
runs or larger runs which require swapping to disk (using virtual
memory).

It seems like the executables are not seeing the extra memory. Even
the large jobs should not need to swap to disk.

Any suggestions if we were expecting too much. Or if we need a
compiler upgrade. Also, we're going to try it under Linux as well.
Any compiler suggestions would be appreciated.

Thanks,

Jim Moser (jmoser_at_kintronic.com)
Staff Enginner-Kintronic Labs
(also posted to comp.lang.fortran)
Received on Wed Oct 08 1997 - 08:23:56 EDT