// stop it.
    blockingCallable.waitForStart();

    // This time, cancel the future for the first task. The task remains running, only the future
    // is cancelled.
    future1.cancel(false);

    // Give the second task a chance to (incorrectly) start up while the first task is running.
    // (This is the assertion that fails.)
    assertThat(future2.isDone()).isFalse();

  fun noNewExchangesOnConnection() {
    codec.carrier.noNewExchanges()
  }

  fun cancel() {
    codec.cancel()
  }

  /**
   * Revoke this exchange's access to streams. This is necessary when a follow-up request is
   * required but the preceding exchange hasn't completed yet.
   */
  fun detachWithViolence() {
    codec.cancel()
    call.messageDone(
      exchange = this,
      requestDone = true,

   * the event source has already been closed or canceled.
   */
  fun cancel()

  fun interface Factory {
    /**
     * Creates a new event source and immediately returns it. Creating an event source initiates an
     * asynchronous process to connect the socket. Once that succeeds or fails, `listener` will be
     * notified. The caller must cancel the returned event source when it is no longer in use.
     */
    fun newEventSource(

	ctx, cancel := context.WithCancel(ctx)

	// reset global variables to start afresh.
	resetTestGlobals()

	// Set globalIsErasure to indicate that the setup uses an erasure
	// code backend.
	globalIsErasure = true

	// Initializing objectLayer for HealFormatHandler.
	objLayer, erasureDirs, xlErr := initTestErasureObjLayer(ctx)
	if xlErr != nil {
		cancel()
		return nil, xlErr
	}

  }

  public void testListenerCalledOnCancelFromRunning() throws Exception {
    exec.execute(task);
    runLatch.await();

    // Task has started up, cancel it while it's running.
    task.cancel(true);
    assertTrue(task.isDone());
    assertTrue(task.isCancelled());
    assertEquals(1, taskLatch.getCount());

    // Wait for the listeners to be called.

		for par := 1; par <= 32; par *= 2 {
			b.Run("par="+strconv.Itoa(par*runtime.GOMAXPROCS(0)), func(b *testing.B) {
				defer timeout(60 * time.Second)()
				ctx, cancel := context.WithTimeout(b.Context(), 30*time.Second)
				defer cancel()
				b.ReportAllocs()
				b.SetBytes(int64(len(payload) * 2))
				b.ResetTimer()
				t := time.Now()
				var ops int64
				var lat int64
				b.SetParallelism(par)

            }
          });
      executor.execute(
          new Runnable() {
            @Override
            public void run() {
              future.cancel(true);
              if (!future.isDone()) {
                errorMessage.set("Cancel call exited before future was complete.");
              }
            }
          });
      try {
        future.get();
      } catch (Throwable t) {

that by default Kotlin's Dispatchers are not used.

Cancellation if implemented sensibly in both directions.
Cancelling a coroutine scope, will cancel the call.
Cancelling a call, will throw a CancellationException

func benchmarkPutObjectPart(b *testing.B, instanceType string, objSize int) {
	// create a temp Erasure/FS backend.
	ctx, cancel := context.WithCancel(b.Context())
	defer cancel()
	objLayer, disks, err := prepareTestBackend(ctx, instanceType)
	if err != nil {
		b.Fatalf("Failed obtaining Temp Backend: <ERROR> %s", err)
	}

            }
          });
      executor.execute(
          new Runnable() {
            @Override
            public void run() {
              future.cancel(true);
              if (!future.isDone()) {
                errorMessage.set("Cancel call exited before future was complete.");
              }
            }
          });
      try {
        future.get();
      } catch (Throwable t) {