public static RegionVersionVector<?> create(VersionSource<?> versionMember, LocalRegion owner) {
    if (versionMember.isDiskStoreId()) {
      return new DiskRegionVersionVector((DiskStoreID) versionMember, owner);
    } else {
      return new VMRegionVersionVector((InternalDistributedMember) versionMember, owner);
    }
  }
this toString method is not thread-safe
geode-core/src/main/java/org/apache/geode/internal/cache/versions/RegionVersionVector.java