public boolean verifyTombstoneCount(AtomicInteger numTombstones) {
    int deadEntries = 0;
    try {
      for (final Object o : getEntryMap().values()) {
        RegionEntry re = (RegionEntry) o;
        if (re.isTombstone()) {
          deadEntries++;
        }
      }
      if (deadEntries != numTombstones.get()) {
        if (logger.isDebugEnabled()) {
          logger.debug("tombstone count ({}) does not match actual number of tombstones ({})",
              numTombstones, deadEntries, new Exception());
        }
        return false;
      } else {
        if (logger.isDebugEnabled()) {
          logger.debug("tombstone count verified");
        }
      }
    } catch (Exception e) {
      // ignore
    }
    return true;
  }
removes a tombstone that has expired locally
geode-core/src/main/java/org/apache/geode/internal/cache/AbstractRegionMap.java