private void checkEventTracker(LocalRegion region, int numberOfEvents) {
    EventTracker tracker = region.getEventTracker();
    ConcurrentMap<ThreadIdentifier, BulkOperationHolder> memberToTags =
        tracker.getRecordedBulkOpVersionTags();
    assertEquals("memberToTags=" + memberToTags, 1, memberToTags.size());
    BulkOperationHolder holder = memberToTags.values().iterator().next();
    // We expect the holder to retain only the last putAll that was performed.
    assertEquals("entryToVersionTags=" + holder.getEntryVersionTags(), numberOfEvents,
        holder.getEntryVersionTags().size());
  }
Test to make sure we don't leak put all events in the event tracker after multiple putAlls
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/event/EventTrackerDUnitTest.java