The two salvaged commits above disagree: #127721 persists gc.auto=0, which
turns the fold's `gc --auto` into a no-op (106 packs stay 106 on git 2.50.1,
2.53.0 and 2.55.0), and the fold itself is exposed to the loop #127721
guards against. Probed on all three gits against a blobless clone whose
commit-graph carries changed-path (Bloom) data:
- gc, `gc --auto`, `maintenance run --task=commit-graph` and
fetch.writeCommitGraph each lazy-fetch the trees of every commit the graph
has not seen (30 unseen commits: 30 fetches, 30 packs), and every lazy
fetch spawns `git maintenance` again. gc.writeCommitGraph=false stops it
(gc: 31 packs -> 1).
- Without a Bloom graph none of that happens, so the keys are a guard, not a
fix for every partial clone.
Changes:
- keys: maintenance.auto, gc.writeCommitGraph, fetch.writeCommitGraph; gc.auto
stays default. Idempotent (no rewrite when already set), `--local`, hidden
console on Windows. install.sh and install.ps1 set the same three keys.
- consolidate_lazy_fetch_packs applies the keys before the fold, so installs
that predate the installer change converge on their next update check.
- the fold runs under bounded_probe_run: subprocess.run(timeout=) kills only
`git gc` and leaves `pack-objects` running (reproduced), and with
GIT_NO_LAZY_FETCH.
- dropped the post-gc mark_unmarked_packs_promisor: gc keeps the .promisor
marker on 2.50.1, 2.53.0 and 2.55.0.
- docs: updating.md troubleshooting entry.