@Test
  public void testClearAndStats() throws Exception {
    DiskRegion dr = ((LocalRegion) testRegion).getDiskRegion();
    assertEquals(0, dr.getStats().getNumEntriesInVM());
    // put a value in the region
    testRegion.put(1L, 1L);
    assertEquals(1, dr.getStats().getNumEntriesInVM());
    testRegion.clear();
    assertEquals(0, dr.getStats().getNumEntriesInVM());
  }
Make sure the disk region stats are set to zero when the region is cleared.
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/DiskRegionClearJUnitTest.java