@Override
        public boolean equals(@Nullable Object obj) {
            if (this == obj) {
                return true;
            }

            if (!(obj instanceof StateKey)) {
                return false;
            }

            final StateKey that = (StateKey) obj;
            return ipOrHost.equals(that.ipOrHost) && port == that.port && isHttp1 == that.isHttp1;
        }
Cleans up empty entries with no activity for more than 1 minute. For reduced overhead, we perform this
only when 1) the last clean-up was more than 1 minute ago and 2) the number of acquisitions % 256 is 0.
core/src/main/java/com/linecorp/armeria/client/DefaultEventLoopScheduler.java