private long delayBeforeNextAttemptMs(long now) {
        long timeSinceAttempt = now - lastMetadataFetchAttemptMs;
        return Math.max(0, refreshBackoffMs - timeSinceAttempt);
    }
Determine if the AdminClient should fetch new metadata.
clients/src/main/java/org/apache/kafka/clients/admin/internals/AdminMetadataManager.java