Abstract: For the shared cache energy in hard real-time multicores with IABA (Interference-Aware Bus Arbiter) bus, a bank-column partitioning optimization method was proposed for the shared cache energy. In this method, the bank-column cache partitioning was optimized to save the shared cache energy on the premise of hard real-time tasks which can be finished before their deadlines. Experimental results demonstrated that the proposal method can effectively reduce the shared cache energy consumption and guarantee that the hard real-time tasks can be finished before their deadlines. Compared with the way-set cache partitioning optimization method, the proposal method can save about 10% energy of the shared cache in 35 nm technology.