Infra: PEP 0 generation makes edit cycle too slow

[hugovk]

When authoring a PEP, the write-build cycle is too slow because we regenerate the pep-0000.rst file (and topic indexes) in-place, which means that the input folder is modified as part of the build.

That triggers a slow rebuild loop each time.

On my machine, a full build (make clean html) takes 35s and a subsequent incremental build (make html) takes 20s.

For similar actions, others reported:

• 50s and 37s
• 58s and 39s
• 5 minutes, and 30 seconds (10 year old laptop)

Another comparison, for me, a full devguide build takes 14s, and 0.815s for incremental. (Although the devguide has ~55 RST files, PEPs have ~635.)

Can we do something so PEP 0 index files (including topic indexes) don't slow down incremental builds?

For reference, private link to 🔒 Discourse discussion.