Before revision:  Finally, by running experiments on Google cluster traces, we show that a careful planning of redundancy according to the tasks' service time distribution can speed up the computing job by an order of magnitude  .
After revision:  Finally, by running experiments on Google cluster traces, we show that a careful planning of redundancy according to the tasks' service time distribution can speed up the computing job by an order of magnitude , and that the optimum level of redundancy depends on the distribution of tasks' service time .