Exclude scheduled-to-stop members from resolver availability#10919
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AvailableMembers/AvailableMemberCount already excluded draining hosts; extend that to hosts with a future stopAt label, via a shared isLeaving predicate. Such a host has announced its departure and reports itself NOT_SERVING, so it should not be offered for new requests, the same way a draining frontend isn't. The consistent-hash lookup ring is left untouched so ownership transfers once, at the scheduled eviction.
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What changed?
AvailableMembers()/AvailableMemberCount()already excludeddraininghosts; extend that to hosts with a futurestopAtlabel. The consistent-hashLookup()ring is left untouched.Why?
A gracefully-stopping history/matching host sets a future
stopAtand reports itselfNOT_SERVING, but stays listed inAvailableMembers(). The frontend deep health check pings those peers, they fail, and a new pod's readiness can flip toNOT_SERVING, extending the rollout. An announced-departing host shouldn't count as available — same asdraining.Leaving hosts stay in the lookup ring rather than being removed early: dropping them diverges ring views across nodes and causes
ShardOwnershipLostchurn during the drain window. Coordinated eviction (#5431) already drops a host from every ring at once, at itsstopAt.How did you test it?
Potential risks
AvailableMemberCount()feeds per-host rate limits, so remaining hosts get slightly more quota during the drain window — the same trade-off already accepted fordraining(#5889), just applied to more hosts.