@Override
    public void beforeSwitchingOplog() {
      cache.getLogger().info("beforeSwitchingOplog");
      if (!switchExpected.get()) {
        fail("unexpected oplog switch");
      }
      if (spaceUsageBefore == -1) {
        // only want to call this once; before the 1st oplog destroy
        dh = dr.getNextDir();
        spaceUsageBefore = dh.getDirStatsDiskSpaceUsage();
      }
    }
Tests if without rolling the region size before close is same as after recreation
geode-core/src/integrationTest/java/org/apache/geode/internal/cache/OplogJUnitTest.java