Adapting resource use to improve performance in a caching memory system

摘要

A memory system, and a method for controlling prestaging activities based upon the availability of resources within the memory system. Prestage requests are stored in a shared memory accessible to a resource controller and one or more memory controllers. When the resource controller determines that there are sufficient unused cache memory and sufficient unused memory device back-end bandwidth available to prestage at least one data track, a message is broadcast to all of the memory controllers. Those memory controllers with sufficient unused throughput accept the prestage requests and copy the associated data tracks from the memory devices to the cache memory. Counters are maintained in the shared memory to track the number of prestage requests in the process of being serviced, and the number of prestaged data tracks already buffered in cache memory and waiting to be accessed by an external host.