SD_task_schedule(taskA, 2, host_list, computation_amount, communication_amount, -1);
SD_task_schedule(taskB, 2, host_list, computation_amount, communication_amount, -1);
SD_task_schedule(taskA, 2, host_list, computation_amount, communication_amount, -1);
SD_task_schedule(taskB, 2, host_list, computation_amount, communication_amount, -1);