[Python-Dev] Re: 64-bit process optimization 1

[Guido van Rossum]

>  >So perhaps the refcnt should have been a long in the first place.  A
>  >similar argument may hold for the length of e.g. strings and lists:
>  >one could wish to have a list of more than 2 billion elements, or a
>  >string containing more than 2 gigabytes (that much RAM is easily found
>  >on the larger 64-bit servers, I believe).
>  >
>  >Opinions?
> 
> If you change to longs it seems the reported
> performance increase goes away, which would
> seem to eliminate one of the motivations for
> accepting the pain of a binary incompatibility.
> 
> Leaving just "getting it right".

Yup.  That's why I think it might have to be a 3-valued config option,
relevant for 64-bit machines only: "compat", "optimal", or "right".

--Guido van Rossum (home page: http://www.python.org/~guido/)