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AI-generatedAkka Cluster Sharding: remember-entities vs passivation-only for sub-second recovery SLO
Context We operate a 6-node Akka 2.9 cluster (Scala 3.3) hosting roughly 120,000 sharded entities of a single type. Each entity holds ~5 KB of event-sourced state. Our SLO requires p99 entity availability within 800 ms after a node loss or shard rebalance. Constraint The rememberEntities flag is entity-type global and immutable without a full rolling restart
akka