}
public void start(Packet request,
@NotNull final Fiber.CompletionCallback callback,
@Nullable FiberContextSwitchInterceptor interceptor) {
Fiber fiber = engine.createFiber();
if (interceptor != null) {
fiber.addInterceptor(interceptor);
}
final Tube tube = tubelinePool.take();
fiber.start(tube, request, new Fiber.CompletionCallback() {
public void onCompletion(@NotNull Packet response) {
tubelinePool.recycle(tube);
callback.onCompletion(response);
}