private void computeDiskDifferences(Map<DiskId, List<ReplicaId>> expectedDiskToReplicaMap,
      Map<DiskId, Set<String>> actualDiskToPartitionMap) {
    foundDiskToPartitionMap = actualDiskToPartitionMap;
    newDiskToReplicaMap = new HashMap<>();
    this.expectedDiskToReplicaMap = expectedDiskToReplicaMap;

    for (Map.Entry<DiskId, List<ReplicaId>> entry : expectedDiskToReplicaMap.entrySet()) {
      DiskId currentDisk = entry.getKey();
      List<ReplicaId> replicas = entry.getValue();
      for (ReplicaId replica : replicas) {
        String partitionID = replica.getPartitionId().toPathString();
        if(!foundDiskToPartitionMap.get(currentDisk).contains(partitionID)) {
          brokenDisks.add(currentDisk);
        }
      }
    }
  }
Compute the differences between the expected and actual disk-to-partition maps. Populate the list of broken
disks.
@param expectedDiskToReplicaMap
@param actualDiskToPartitionMap
ambry-store/src/main/java/com/github/ambry/store/ReplicaPlacementValidator.java