Program very slow to finish

Fred fredNo at nospamco.com
Wed Nov 14 12:58:51 EST 2001


Thanks, I'll give that a try.  With all the talk of windows free()
problems
discussed above I was trying to figure out what I could do on Digital
Unix with 1Gb of memory :-)



Alexei Zverovitch wrote:
> 
> Fred <fredNo at nospamco.com> wrote in news:3BE41CBE.94AED22 at nospamco.com:
> 
> > Python 2.1.1 (#3, Oct 25 2001, 12:54:40) [C] on osf1V4
> 
> Since you're running Digital Unix, you might want to
> try tweaking the __fast_free_max et al variables used
> by the system malloc(). 'man malloc' is your friend
> (I believe you'll need to re-link the python executable
> if you want to change those variables).
> 
> We've had a similar problem recently when a (C++)
> program was taking ages to free() .5 million small
> structures. It turned out that most of the time was
> spent by free() coalescing memory blocks as they
> were being deallocated. Increasing __fast_free_max
> solved the problem (IIRC the execution time was
> reduced by several orders of magnitude).
> 
> You may be seeing the same (or similar) behaviour.
> 
> Cheers
> Alexei
> --
> alexei (at) barclays (dot) net



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