@Override
    public LlapServiceInstance getInstance(String name) {
      Collection<LlapServiceInstance> instances = getAll();
      for(LlapServiceInstance instance : instances) {
        if (instance.getWorkerIdentity().equals(name)) {
          return instance;
        }
      }
      return null;
    }
A dynamically changing instance in an Llap Service. Can become inactive if failing or can be
blacklisted (set to 0 capacity) if too slow (See: BlacklistingLlapMetricsListener).
llap-client/src/java/org/apache/hadoop/hive/llap/registry/impl/LlapZookeeperRegistryImpl.java