[Python-3000] Is reference counting still needed?

[Neil Schemenauer]

Erno Kuusela <erno at iki.fi> wrote:
> The refcounting vs generational GC reasoning I've heard argues that
> refcounting is less cache-friendly

I believe that's correct.  A state of the art generational GC would
outperform reference counting, even given Python's enormous
allocation rate.  However, those systems require man years of
development effort and are not widely portable.

Perhaps even more seriously, any system that could outperform
refcounting would require moving objects (at least, AFAIK).  If we
would want to use such a system, extensions would have to be written
in a completely different manner.

The portability problem might be solved by have a pluggable GC
system: high performance on platforms that support it, simple
implementation (e.g.  mark and sweep) on platforms that don't.

  Neil