private void checkIfBatchExpirationShouldBeForced() {
      if (testHook_forceExpirationCount > 0) {
        return;
      }
      if (GC_MEMORY_THRESHOLD <= 0.0) {
        return;
      }
      if (batchExpirationInProgress) {
        return;
      }
      if (expiredTombstones.size() <= (EXPIRED_TOMBSTONE_LIMIT / 4)) {
        return;
      }
      if (FORCE_GC_MEMORY_EVENTS || isFreeMemoryLow()) {
        forceBatchExpiration = true;
        if (logger.isDebugEnabled()) {
          logger.debug("forcing batch expiration due to low memory conditions");
        }
      }
    }
Returns true if keys needs to be tracked for clients registering interests on PR.
geode-core/src/main/java/org/apache/geode/internal/cache/TombstoneService.java