public static RegionVersionVector<?> create(boolean persistent, DataInput in)
      throws IOException, ClassNotFoundException {
    RegionVersionVector<?> rvv;
    if (persistent) {
      rvv = new DiskRegionVersionVector();
    } else {
      rvv = new VMRegionVersionVector();
    }
    InternalDataSerializer.invokeFromData(rvv, in);
    return rvv;
  }
this toString method is not thread-safe
geode-core/src/main/java/org/apache/geode/internal/cache/versions/RegionVersionVector.java