Re: NEC-LIST: NEC Execution Times Under Windows

Kintronic Labs wrote:
>
> 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)

Jim, I just took delivery on a Gateway 2000 G6-300XL Pentium II
system. In purchasing the system and working with Gateway Sales and
Tech Support, I was very surprised to learn that Windows 95 is
*unable* to make use of any memory above 64 MBytes. I initially
intended to upgrade to 120 MBytes, but after learning that bit of
wisdom I quickly changed the order to upgrade from a 19" display to a
21" display. It seems that NT can use all the memory you throw at it,
and I suppose that Unix does as well, but not W95.

So, maybe your results are not all that far off, after all, since you
are only using 64 MBytes of that 128 Megs.

-- 
73, George
W5YR (original, not vanity)
AutoPOWER Systems
Fairview, TX