@Test
  public void trackersLoadedForAllOldLogs() throws Exception {
    for (int i = 0; i <= 20; ++i) {
      procStore.insert(new TestProcedure(i), null);
      if (i > 0 && (i % 5) == 0) {
        LoadCounter loader = new LoadCounter();
        storeRestart(loader);
      }
    }
    assertEquals(5, procStore.getActiveLogs().size());
    for (int i = 0; i < procStore.getActiveLogs().size() - 1; ++i) {
      ProcedureStoreTracker tracker = procStore.getActiveLogs().get(i).getTracker();
      assertTrue(tracker != null && !tracker.isEmpty());
    }
  }
Tests that tracker for all old logs are loaded back after procedure store is restarted.
hbase-procedure/src/test/java/org/apache/hadoop/hbase/procedure2/store/wal/TestWALProcedureStore.java