view CONTRIBUTING @ 33799:05264fc9d8d6

util: make nogc effective for CPython

279cd80059d4 made `util.nogc` a no-op. It was to optimize PyPy. But it slows
down CPython if many objects (like 300k+) are created.

For example, running `hg log -r .` without extensions in `hg-committed` with
14k+ obsmarkers have the following times:

  before        | after
  hg    | chg   | hg    | chg
  -----------------------------
  1.262 | 0.860 | 1.077 | 0.619 (seconds, best of 20 runs)

Therefore let's re-enable nogc for CPython.

Differential Revision: https://phab.mercurial-scm.org/D402

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