A mass storage subsystem includes one or more data stores for storing information for access by one or more devices such as host computers, and a cache memory, and connects to a slave mass storage subsystem which provides mirrored storage for the information stored in its (that is, the mass storage subsystem's) data stores. When a host computer is to access information, the information is cached in the cache memory by the data stores, and the host computer will retrieve the information from the cache memory. In addition, the host computers can update information through the cache memory. Over a period of time, the mass storage subsystem gathers statistics relating to cache misses for respective chunks, each chunk comprising a relatively large number contiguous storage locations as maintained by the data stores, and will periodically cache information from entire chunks. Generally, if there is a relatively large number of cache misses for a chunk over a period of time, the chunk is being randomly accessed by the host computers, and, by caching the entire chunk, the likelihood of having a cache miss for that chunk will be eliminated. In addition, caching chunks in the slave mass storage subsystem's cache memory will increase the utilization of the cache memory of the slave mass storage subsystem.
|Original language||English GB|
|IPC||G06F 12/ 08 A I|
|State||Published - 14 Dec 1999|