[Python-Dev] whither PEP 407 and 413 (release cycle PEPs)?

["Martin v. Löwis"]

On 01.06.2012 19:33, Brett Cannon wrote:
> Are these dead in the water or are we going to try to change our
> release cycle? I'm just asking since 3.3 final is due out in about 3
> months and deciding on this along with shifting things if we do make
> a change could end up taking that long and I suspect if we don't do
> this for 3.3 we are probably never going to do it for Python 3 series
> as a whole.

I'm -1 on both PEPs.

For PEP 407, I fail to see what problem it solves. The PEP is short on
rationale, so let me guess what the motivation for the PEP is:

- Some people (Barry in particular) are in favor of timed releases.
   I don't know what the actual motivation for timed releases is, but
   ISTM that PEP 407 is an attempt to make Python generate timed
   releases. I'm -1 on that because of the additional effort for release
   managers. In particular, a strict schedule will limit vacation time,
   and require the release team to coordinate their vacation plans.
   With two alpha, one beta, and one rc, plus LTS bugfix releases, there
   may well be one release of some Python version every month.

- Some contributors are worried about getting their contributions "out",
   and some core committers are worried that we get fewer contributions
   because of that.

   While I well recall the feeling of getting changes "out", the real
   concerns only exist for the very first contribution:
   * Those gurus on python-dev are certainly working on a fix for this
     very important issue already, how could they not have noticed?
     My work will be futile, and they'll fix it the day before I submit
     the patch.
   * Now that the patch is uploaded, can somebody *please* review it?
     How hard can it be to look over 20 lines of code?
   * Now that they committed it, when can I start telling my friends
     about it? The next release takes ages, and waiting is not fun.

   While these concerns are all real, it's really a matter of contributor
   education to deal with them, The longer people contribute to open
   source (or participate in any kind of software development), the
   more they learn that this is just how things work. The PEP really
   only addresses the third concern, whereas I think that the second
   is much more relevant.

   As for us not getting enough contributions: can we please worry
   about that when we have all patches processed that already have
   been contributed?

I also think that the PEP will have negative effect on Python users:
incompatible changes will spread faster (people will think that it's
ok to break stuff since it was announced for three releases, when
it wasn't actually announced in the last LTS). Users will feel the
urgency of updating, and at the same time uneasiness about doing
so as it may break stuff. People *already* get behind by two or
three releases (in the 2.x series), getting behind 10 releases
just will make them feel sad.

For PEP 413, much the same concerns apply. In addition, I think it's
too complicated, both for users, and for the actual technical
implementation.

Regards,
Martin