The 5-10s RPCs that broke calling were not cold-start — they were
per-RPC sequential rqlite reads, each forwarded to a raft leader that
geography-blind election had placed on a 256ms-distant node.
Lever A (serverless): cache function metadata + env vars in-process
(5s TTL, invalidated on deploy/enable/disable/delete) and stop the hot
invoke path re-fetching the function for the authorization check —
removes ~820ms of leader-routed pre-flight reads from every op.
Lever B (namespace): a locality-aware leadership reconciler hands raft
leadership off a geographically-isolated namespace leader to the nearest
co-located voter, via rqlite's transfer-leadership API. All nodes stay
voters — membership, quorum and fault tolerance are unchanged. Cuts the
per-hop cost from ~274ms to ~20ms when a distant node had become leader.
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