private void obtainWriteLocksForClear(RegionEventImpl regionEvent,
      Set<InternalDistributedMember> participants) {
    lockLocallyForClear(getDistributionManager(), getMyId(), regionEvent);
    DistributedClearOperation.lockAndFlushToOthers(regionEvent, participants);
  }
obtain locks preventing generation of new versions in other members
geode-core/src/main/java/org/apache/geode/internal/cache/DistributedRegion.java