The drain comment and the architecture docs stated the zero-budget band
relative to the auto-compact threshold as if 0.8 were universal
("well below the auto-compact threshold"); with an operator-set
auto_compact_pct under the ~70% zero point the claim reads inverted.
State the geometry against the DEFAULT threshold and make explicit what
was always true of the mechanism: the trigger's predicate is the
exhausted budget itself, never a threshold, so with low thresholds the
owed path compacts first and the trigger is its bail/insufficient
backstop.
Patrick Buckley
b38e9be17c