* permits per second:
 *
 * {@snippet :
 * final RateLimiter rateLimiter = RateLimiter.create(5000.0); // rate = 5000 permits per second
 * void submitPacket(byte[] packet) {
 *   rateLimiter.acquire(packet.length);
 *   networkService.send(packet);
 * }
 * }
 *
 * <p>It is important to note that the number of permits requested <i>never</i> affects the