long getOnHostPartitionSealedCount() {
      if (!instanceNameToAmbryDataNode.containsKey(selfInstanceName)) {
        // Frontend nodes
        return 0L;
      }
      AmbryDataNode dataNode = instanceNameToAmbryDataNode.get(selfInstanceName);
      Map<String, AmbryReplica> replicas = ambryDataNodeToAmbryReplicas.get(dataNode);
      if (replicas == null) {
        return 0L;
      }
      return replicas.values().stream().filter(AmbryReplica::isSealed).count();
    }
@return the count of partition that are on this host and sealed.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/HelixClusterManager.java