public void start() {
    if (isRunning) return;

    logger.info("Starting timer with delay of {} seconds ", scheduledDelayInMs / 1000);
    scheduleTask(scheduledDelayInMs);
    isRunning = true;
  }
Starts the timer.
If the timer is already running, it does nothing.
ambry-utils/src/main/java/com/github/ambry/utils/ExtendableTimer.java