@Test
  public void testSuspectMembersCalledThroughSuspectThread() throws Exception {
    installAView();

    gmsHealthMonitor.suspect(mockMembers.get(1), "Not responding");

    await().untilAsserted(
        () -> verify(messenger, atLeastOnce()).send(any(SuspectMembersMessage.class)));

    Assert.assertTrue(gmsHealthMonitor.getStats().getSuspectsSent() > 0);
  }
Checks whether suspect thread sends suspectMembers message
geode-membership/src/integrationTest/java/org/apache/geode/distributed/internal/membership/gms/fd/GMSHealthMonitorJUnitTest.java