Arrow Resilience Kit/com.sorinirmies.arrow.resiliencekit/Bulkhead

Bulkhead

Bulkhead pattern implementation for concurrency isolation.

Limits the number of concurrent calls to protect shared resources from overload. When the maximum number of concurrent calls is reached, additional calls are either queued (up to BulkheadConfig.maxWaitingCalls) or rejected immediately.

Basic usage:

val bulkhead = Bulkhead.create(config = BulkheadConfig(maxConcurrentCalls = 5))

val result = bulkhead.execute {
    callExternalService()
}

With waiting queue:

val bulkhead = Bulkhead.create(config = BulkheadConfig(
    maxConcurrentCalls = 10,
    maxWaitingCalls = 20,
    maxWaitDuration = 5.seconds
))

With fallback:

val result = bulkhead.executeOrFallback(
    fallback = { cachedResponse() }
) {
    callExternalService()
}

DSL builder:

val bulkhead = bulkhead {
    maxConcurrentCalls = 5
    maxWaitingCalls = 10
    maxWaitDuration = 3.seconds
}

With listener:

bulkhead.addListener(object : BulkheadListener {
    override fun onCallRejected() {
        metrics.incrementRejected()
    }
})

Statistics:

val stats = bulkhead.statistics()
println("Total: ${stats.totalCalls}, Rejected: ${stats.rejectedCalls}")
println("Utilization: ${stats.utilizationRate * 100}%")