On Thu, 14 Apr 2016 at 15:14 Victor Stinner <victor.stinner@gmail.com> wrote:
2016-04-14 23:29 GMT+02:00 Barry Warsaw <barry@python.org>:
> I can see why you might want a global version number, but not doing so would
> eliminate an implicit reliance on the GIL, or in a GIL-less implementation
> <wink> a lock around incrementing the global version number.

It's not like the builtin dict type is going to become GIL-free... So
I think that it's ok to use a global version.

A very few know that, but the GIL has some advantages sometimes...

And even if it was GIL-free you do run the risk of two dicts ending up at the same version # by simply mutating the same number of times if the counters were per-dict instead of process-wide.