Running very big jobs with FDS

[Kevin McGrattan <kevin.mcgrattan@nist.gov>]

All

A number of you have reported having trouble running large
jobs with FDS. I think
there's a relatively simple solution to the problem, but I
need some help to test
it. For those of you who have not encountered this problem,
there is no need to
do anything. This fix is only for those who have encountered
an error message like
this:

"forrtl: severe: Program Exception - stack overflow"

The stack is a memory construct used in running any computer
program. The bigger
the job, the bigger the stack size needs to be. Most
operating systems do not
require the user to specify a limit on the stack size, and
some let the user just
specify ``unlimited'' as a default. Windows requires a
finite stack size, and when
I compile FDS, I use a stack size of 10 Mb. For most jobs
using less than a million
cells, this limit is sufficient. To avoid having to
recompile FDS, one can run a
small filter program called ``editbin'' to change the stack
limit in the binary
file fds2.exe.

To do this, go to the ftp site
ftp://ftp.nist.gov/pub/bfrl/mcgratta/FDS2/PC and
grab the file called editbin.exe
Put this file in the same directory as your fds2.exe file,
and from the DOS shell
run the following command

editbin /stack:20000000 fds2.exe

Here I am using 20000000 bytes (20 Mb) just as an example.
You might have to 
experiment with the number to get what you need. Remember
that I compiled with
10 Mb.

So try this out if you've had trouble with big jobs, and let
me know ASAP is it
works for you.

Kevin


-- 
Kevin McGrattan
National Institute of Standards and Technology
100 Bureau Drive, Stop 8663
Gaithersburg MD 20899-8663

Telephone: (301) 975 2712
FAX:       (301) 975 4052