public static Sensor throttleTimeSensor(SenderMetricsRegistry metrics) {
        Sensor produceThrottleTimeSensor = metrics.sensor("produce-throttle-time");
        produceThrottleTimeSensor.add(metrics.produceThrottleTimeAvg, new Avg());
        produceThrottleTimeSensor.add(metrics.produceThrottleTimeMax, new Max());
        return produceThrottleTimeSensor;
    }
Wake up the selector associated with this send thread
clients/src/main/java/org/apache/kafka/clients/producer/internals/Sender.java