private boolean shutdown(long timeout, TimeUnit unit) throws InterruptedException {
if (!isShutdown.compareAndSet(false, true)) return true;
long start = System.nanoTime();
boolean success = true;
for (HostConnectionPool pool : pools.values())
success &= pool.shutdown(timeout - Cluster.timeSince(start, unit), unit);
return success;
}
private void shutdown() {
if (!isShutdown.compareAndSet(false, true)) return;
for (HostConnectionPool pool : pools.values()) pool.shutdown();
}