private void loadMeta() throws IOException {
    // TODO: use a thread pool
    regionStateStore.visitMeta(new RegionMetaLoadingVisitor());
  }
Attempt to load {@code regionEncodedName} from META, adding any results to the
{@link #regionStateStore} Is NOT aware of replica regions.
@param regionEncodedName encoded name for the region to be loaded from META.
@throws IOException If some error occurs while querying META or parsing results.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java