@Test
  public void testPhiAdaptionToFrequentGCPause() {
    long[] interval =
        new long[] {
          sec,
          sec,
          sec,
          15 * sec,
          (long) (0.1 * sec),
          sec,
          sec,
          sec,
          15 * sec,
          (long) (0.1 * sec),
          sec,
          sec
        };
    List<AbstractHeartbeatSample> history = fromInterval(interval, 21 * sec);
    Assert.assertFalse(fixedDetector.isAvailable(id, history));
    Assert.assertTrue(phiAccrualDetector.isAvailable(id, history));
  }
When the system load is high, we may observe exceptionally long GC pause If the GC pause is
very often, Phi can be adaptive to the new environment in this case, there are 2 long GC pause
in history when a new GC with 21s pause occurs, Phi takes it normal while Fixed will fail.
iotdb-core/confignode/src/test/java/org/apache/iotdb/confignode/manager/load/cache/detector/DetectorTest.java