A secondary texture cache is used commonly by a plurality of texture units, and stores part of texture data in a main memory. A cache controlling CPU controls a refill operation from the main memory to the secondary texture cache in accordance with cache misses of the plurality of texture units, so as to suppress occurrence of thrashing in the secondary texture cache. The cache controlling CPU suppresses occurrence of the refill operation when the plurality of operating units access an identical memory address with a predetermined time difference.