The mixed-version rolling upgrade suite asserted a single list_objects_v2
snapshot seconds after restarting a node. Peers keep a restarted node's
drive in Suspect/Returning for ~probe_interval(2s) x success_threshold(3),
and while one drive is excluded the strict listing quorum (write quorum,
3 of 4) drops objects that were themselves legally written at 3/4 during
an earlier node's identical post-restart window, under-counting the
listing (observed as 254 vs 258 in CI) even though every object still
GETs correctly. Replace the snapshot asserts with a bounded convergence
poll; a real upgrade data-loss regression still fails after the deadline.
唐小鸭