public void startRegisterInterest() {
    getImageState().writeLockRI();
    try {
      cache.registerInterestStarted();
      riCnt++;
    } finally {
      getImageState().writeUnlockRI();
    }
  }
Bump this number any time an incompatible change is made to the snapshot format.
geode-core/src/main/java/org/apache/geode/internal/cache/LocalRegion.java