A memory accessing agent includes a memory access generating circuit and a memory controller. The memory access generating circuit is adapted to generate multiple memory accesses in a first ordered arrangement. The memory controller is coupled to the memory access generating circuit and has an output port, for providing the multiple memory accesses to the output port in a second ordered arrangement based on the memory accesses and characteristics of an external memory. The memory controller determines the second ordered arrangement by calculating an efficient row burst value and interrupting multiple row-hit requests to schedule a row-miss request based on the efficient row burst value.