Retain Store

RetainStore serves retained messages (read-dominant). It runs as a stateful service on the base-kv overlay cluster; store_name for API headers: retain.store.

Default balancers

balancerFactory FQN	Role	Default parameters (load rules)
org.apache.bifromq.retain.store.balance.ReplicaCntBalancerFactory	Keep replica count per range to targets	- votersPerRange: 3 - learnersPerRange: -1
org.apache.bifromq.retain.store.balance.RangeSplitBalancerFactory	Split hot/large ranges to sustain throughput	- maxRangesPerStore: (availableProcessors / 4) -maxCPUUsage: 0.8 -maxIODensity: 100 - ioNanosLimit: 30000

Defaults are set in retainStoreConfig.balanceConfig.balancers in starter config.