[Python-Dev] Investigating Python memory footprint of one real Web application

[Antoine Pitrou]

On Fri, 20 Jan 2017 13:40:14 +0100
Christian Heimes <christian at python.org> wrote:
> 
> IIRC Thomas Wouters (?) has been working on a patch to move the ref
> counter out of the PyObject struct and into a dedicated memory area. He
> proposed the idea to improve cache affinity, reduce cache evictions and
> to make CoW more efficient.

> Especially modern ccNUMA machines with
> multiple processors could benefit from the improvement, but also single
> processor/multi core machines.

Moving the refcount out of the PyObject will probably make increfs /
decrefs more costly, and there are a lot of them.  We'd have to see
actual measurements if a patch is written, but my intuition is that the
net result won't be positive.

Regards

Antoine.