Upper memory limit

Fri May 17 16:34:41 EDT 2002

Siegfried Gonzi wrote:

> I write the array (400 000 of lines) into a Numeric array (NIL becomes
> -1.0). I repeat the task 10 times in a Python function.

I'm still confused. do you call the F5 code from Python? Using Python to
manipulate a Numeric array crated by the Fortran code? If so, I suspect
that that is your memory leak.

> The Fortran 95
> (F compiler from imagine1) takes on my laptop under Windows XP about 5
> minutes for 10 reading cycles. The Fortran version collects about 133MB
> of RAM
does it use more RAM each time it reads the file? If so, you have a
memory leak.

> The same task now  on my 1000 MHz Celeron, 256MB, laptop takes
> theoretically about 30 minutes; but practically it never ends. Beginning
> at the 10. reading cycle the system wreaks havoc (the first 9 readings
> are okay and every file access takes 60MB RAM; here the RAM consumption
> from one cycle to the next is constant; 

hmm. that is odd. The memeory use is constant 60MB for the first 9
readings, and then things go wrong?

post some code, if you wnat hel figuring it out.

> I did the same on my new installed Linux on my stationary machine
> (Pentium III 450MHz, 128MB RAM). Python takes on this machine 2 times
> longer than on my 1000Mhz Celeron (For comparison I write here the ideal
> situation if Python had stopped in 30 minutes on my Celeron laptop).
> After completing the task the system goes on normal.
> 
> I did the same test on the same stationary machine but now under Windows
> NT 4.0 and Python. On Windows NT 4.0 the Python file reading function
> takes exactly the same amount of time than the version under Linux *and*
> after completing the task nothing happens and the system remains
> *stable*.

It does sounf like you have an XP problem.

-Chris

-- 
Christopher Barker, Ph.D.
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