private void closeHeapEvictor() {
    HeapEvictor evictor = heapEvictor;
    if (evictor != null) {
      evictor.close();
    }
  }
Returns true if caller waited on the {@code isClosedLatch}.
geode-core/src/main/java/org/apache/geode/internal/cache/GemFireCacheImpl.java