The 20 % brake skipped a category and wiped its marks every night once a
fifth of it looked unreferenced. Any user could push a small install over
that line, a backlog from #2924 started braked, and a second install on the
same bucket below the line was not caught at all. It is gone:
- Each pass leaves a trek-owner-<install id> marker at the root of every
category it judges. A category holding another install's marker is
skipped as foreign_install, one where the marker cannot be written as
owner_unknown. Backups leave the markers out.
- The install id lives in app_settings outside the storage.* prefix. The
switch is stored as that id, so a database from another install reads as
off, and every reopen (a restore) writes this install's id back, turns
deletion off and drops the marks, confirmations and reports.
- More than a fifth unreferenced still marks and reports, but deletes only
after an admin confirmed the count shown (POST .../reclaim/confirm). A
larger count later waits again.
A skip no longer touches the marks, so a failed listing or lookup does not
restart the week. Check now runs in the background and answers 202; the
admin state says running and keeps the last deleting report apart, so a
report-only check never resets what was freed. A pass that deletes writes a
system audit entry, a pass that stops or fails keeps its partial counts and
marks the rest interrupted, a backend error stops deleting in its category,
and deleting stops for the rest of the pass once the switch is off or a
backup is reading the uploads. The usage scan waits for a pass still
running.
Sources read each category once per pass and answer the pre-delete
re-check with a query narrowed to the keys' plain runs. Bare names keep
their raw spelling (a '#', '?' or trailing blank is part of an upload's
name), and local roots are resolved through their symlinks before the
overlap check. A pass lists only a category's root.
Maurice
790fccb92c