Before revision:  For matrix multiplication, we use codes to leverage the plethora of nodes and alleviate the effects of stragglers. We show that if the number of  workers is n, and the runtime of each subtask has an exponential tail, the optimal coded matrix multiplication is \Theta(\log n) times faster than the uncoded matrix multiplication.
After revision:  For matrix multiplication, we use codes to alleviate the effect of stragglers, and show that if the number of workers is n, and the runtime of each subtask has an exponential tail, the optimal coded matrix multiplication is \Theta(\log n) times faster than the uncoded matrix multiplication.