void schedule() {
			if (scheduled.compareAndSet(false, true)) {
				long delay = Math.max(0, quietPeriod.get() -
						(System.currentTimeMillis() - latestContainer.get().timestamp));
				logger.info("Scheduling deployments to new container(s) in {} ms ", delay);
				executorService.schedule(this, delay, TimeUnit.MILLISECONDS);
			}
			else {
				logger.trace("Container deployment already scheduled");
			}
		}
Schedule new container module deployments. This is scheduled
for execution {@link #quietPeriod} milliseconds after the
latest container arrival. If this runnable has already been
scheduled, invoking this method has no effect.
spring-xd-dirt/src/main/java/org/springframework/xd/dirt/server/admin/deployment/zk/ContainerListener.java