/** {@inheritDoc} */
    @Override
    protected void body() throws InterruptedException, IgniteInterruptedCheckedException {
      if (log.isDebugEnabled()) log.debug("GC worker started.");

      File workTokDir = tokDir.getParentFile();

      assert workTokDir != null;

      boolean lastRunNeeded = true;

      while (true) {
        try {
          // Sleep only if not cancelled.
          if (lastRunNeeded) Thread.sleep(GC_FREQ);
        } catch (InterruptedException ignored) {
          // No-op.
        }

        if (log.isDebugEnabled()) log.debug("Starting GC iteration.");

        cleanupResources(workTokDir);

        // Process spaces created by this endpoint.
        if (log.isDebugEnabled()) log.debug("Processing local spaces.");

        for (IpcSharedMemoryClientEndpoint e : endpoints) {
          if (log.isDebugEnabled()) log.debug("Processing endpoint: " + e);

          if (!e.checkOtherPartyAlive()) {
            endpoints.remove(e);

            if (log.isDebugEnabled()) log.debug("Removed endpoint: " + e);
          }
        }

        if (isCancelled()) {
          if (lastRunNeeded) {
            lastRunNeeded = false;

            // Clear interrupted status.
            Thread.interrupted();
          } else {
            Thread.currentThread().interrupt();

            break;
          }
        }
      }
    }
  /**
   * JUnit.
   *
   * @throws Exception If failed.
   */
  @SuppressWarnings({"TooBroadScope"})
  public void testRestarts() throws Exception {
    int duration = 60 * 1000;
    int qryThreadNum = 10;
    final long nodeLifeTime = 2 * 1000;
    final int logFreq = 20;

    final IgniteCache<Integer, Integer> cache = grid(0).cache(null);

    assert cache != null;

    for (int i = 0; i < KEY_CNT; i++) cache.put(i, i);

    assertEquals(KEY_CNT, cache.localSize());

    final AtomicInteger qryCnt = new AtomicInteger();

    final AtomicBoolean done = new AtomicBoolean();

    IgniteInternalFuture<?> fut1 =
        multithreadedAsync(
            new CAX() {
              @Override
              public void applyx() throws IgniteCheckedException {
                while (!done.get()) {
                  Collection<Cache.Entry<Integer, Integer>> res =
                      cache.query(new SqlQuery(Integer.class, "_val >= 0")).getAll();

                  assertFalse(res.isEmpty());

                  int c = qryCnt.incrementAndGet();

                  if (c % logFreq == 0) info("Executed queries: " + c);
                }
              }
            },
            qryThreadNum);

    final AtomicInteger restartCnt = new AtomicInteger();

    CollectingEventListener lsnr = new CollectingEventListener();

    for (int i = 0; i < GRID_CNT; i++)
      grid(i).events().localListen(lsnr, EventType.EVT_CACHE_REBALANCE_STOPPED);

    IgniteInternalFuture<?> fut2 =
        multithreadedAsync(
            new Callable<Object>() {
              @SuppressWarnings({"BusyWait"})
              @Override
              public Object call() throws Exception {
                while (!done.get()) {
                  int idx = GRID_CNT;

                  startGrid(idx);

                  Thread.sleep(nodeLifeTime);

                  stopGrid(idx);

                  int c = restartCnt.incrementAndGet();

                  if (c % logFreq == 0) info("Node restarts: " + c);
                }

                return true;
              }
            },
            1);

    Thread.sleep(duration);

    done.set(true);

    fut1.get();
    fut2.get();

    info("Awaiting rebalance events [restartCnt=" + restartCnt.get() + ']');

    boolean success = lsnr.awaitEvents(GRID_CNT * 2 * restartCnt.get(), 15000);

    for (int i = 0; i < GRID_CNT; i++)
      grid(i).events().stopLocalListen(lsnr, EventType.EVT_CACHE_REBALANCE_STOPPED);

    assert success;
  }