CACHE MEMORY WRITE-BACK DEVICE, CACHE MEMORY WRITE-BACK SYSTEM, CACHE MEMORY WRITE-BACK METHOD, AND CACHE MEMORY WRITE-BACK PROGRAM

摘要

PROBLEM TO BE SOLVED: To suppress the reoccurrence of a write back to main memory, prevent the system bus from being occupied during the write back, and prevent a cache overhead as much as possible.SOLUTION: A cache memory write-back device 1 comprises: a detection unit 12b, connected to main memory and cache memory, for detecting a dirty line by scanning the cache lines of the cash memory every prescribed cycle; a buffer unit 17 for temporarily storing the detected dirty line; a counter unit 12a for incrementing the count value of the detected dirty line every prescribed cycle; and a monitoring unit 14 for writing the detected dirty line back to the main memory in correspondence to that the count value becomes larger than a threshold.