public void messageSent(long bytes, long sendTimeNanos) {
        long latencyMicros = TimeUnit.NANOSECONDS.toMicros(StatsCollector.currentNanos() - sendTimeNanos);
        messagesSent.increment();
        bytesSent.add(bytes);
        sendLatencyMicros.recordValue(latencyMicros);
        totalMessagesSent.increment();
        totalBytesSent.add(bytes);
        totalSendLatencyMicros.recordValue(latencyMicros);
    }
The max send time of all messages received.
Used to determine whether any consumer catches up to a specific time.
tools/src/main/java/org/apache/kafka/tools/automq/perf/Stats.java