queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {
			return nil, fmt.Errorf("unable to initialize the queue store of Redis `%s`: %w", id, err)
		}
	}

	pool := &redis.Pool{
		MaxIdle:     3,
		IdleTimeout: 2 * 60 * time.Second,
		Dial: func() (redis.Conn, error) {

import java.util.NavigableMap;
import java.util.NavigableSet;
import java.util.Optional;
import java.util.OptionalDouble;
import java.util.OptionalInt;
import java.util.OptionalLong;
import java.util.Queue;
import java.util.Random;
import java.util.Set;
import java.util.SortedMap;
import java.util.SortedSet;
import java.util.UUID;
import java.util.concurrent.BlockingDeque;

    // contract.
    // This is somewhat annoying, but turns out to be very fast in practice. Alternatively, we could
    // drop the contract on the method that enforces this queue like behavior since depending on it
    // is likely to be a bug anyway.

    // N.B. All writes to the list and the next pointers must have happened before the above

		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {
			return nil, fmt.Errorf("unable to initialize the queue store of NSQ `%s`: %w", id, err)
		}
	}

	target := &NSQTarget{
		id:         event.TargetID{ID: id, Name: "nsq"},
		args:       args,
		loggerOnce: loggerOnce,
		store:      queueStore,

	// This is the assumed size of bigger buffers and allocation size.
	biggerBufMin = 32 << 10

	// This is the maximum size of bigger buffers.
	biggerBufMax = maxBufferSize

	// If there is a queue, merge up to this many messages.
	maxMergeMessages = 50

	// clientPingInterval will ping the remote handler every 15 seconds.
	// Clients disconnect when we exceed 2 intervals.
	clientPingInterval = 15 * time.Second

	apiRejectedInvalidTotalMD = NewCounterMD(apiRejectedInvalidTotal,
		"Total number of invalid requests", "type")

	apiRequestsWaitingTotalMD = NewGaugeMD(apiRequestsWaitingTotal,
		"Total number of requests in the waiting queue", "type")
	apiRequestsIncomingTotalMD = NewGaugeMD(apiRequestsIncomingTotal,
		"Total number of incoming requests", "type")

	apiRequestsInFlightTotalMD = NewGaugeMD(apiRequestsInFlightTotal,

		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {
			return nil, fmt.Errorf("unable to initialize the queue store of AMQP `%s`: %w", id, err)
		}
	}

	target := &AMQPTarget{
		id:         event.TargetID{ID: id, Name: "amqp"},
		args:       args,
		loggerOnce: loggerOnce,
		store:      queueStore,

		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {
			cancel()
			return nil, fmt.Errorf("unable to initialize the queue store of Webhook `%s`: %w", id, err)
		}
	}

	target := &WebhookTarget{
		id:         event.TargetID{ID: id, Name: "webhook"},
		args:       args,
		loggerOnce: loggerOnce,
		transport:  transport,

		queueStore = store.NewQueueStore[event.Event](queueDir, args.QueueLimit, event.StoreExtension)
		if err := queueStore.Open(); err != nil {
			return nil, fmt.Errorf("unable to initialize the queue store of MQTT `%s`: %w", id, err)
		}
	}

	target := &MQTTTarget{
		id:         event.TargetID{ID: id, Name: "mqtt"},
		args:       args,
		store:      queueStore,
		quitCh:     make(chan struct{}),

		Help:      "Total number of objects queued for replication in the last full minute",
		Type:      gaugeMetric,
	}
}

func getClusterReplCurrQueuedBytesMD() MetricDescription {
	return MetricDescription{
		Namespace: nodeMetricNamespace,
		Subsystem: replicationSubsystem,
		Name:      currInQueueBytes,
		Help:      "Total number of bytes queued for replication in the last full minute",