Predictive cache system

A data processing system including a predictive cache memory subsystem comprising:

• a cache memory for storing objects retrieved from secondary memory;
• pattern memory storing separate sets of object access patterns generated from prior accesses of the data processing system processing in different contexts;
• a prefetcher responsive to a current access pattern during operation of the data processing system for predicting, from like object access patterns stored in pattern memory, accesses to objects and for prefetching predicted objects to store the predicted objects in cache memory, the prefetcher comparing the time of access order of a current access pattern to a sample length of patterns to form a prediction from a remaining length of selected patterns, the remaining length of the selected patterns being dynamically controlled to increase the efficiency of prediction, predictions being made from combinations of access patterns stored in pattern memory;
• and
• a trainer for generating access patterns stored in pattern memory from traces of accesses recorded during processing of the data processing system, the trainer generating statistical information for the stored accessed patterns including accuracy of prediction and deleting patterns of insufficient accuracy from pattern memory.

A method of cache memory management comprising:

• generating access patterns from traces of object accesses recorded during processing of a data processing system in a context;
• storing the access patterns;
• monitoring a current access pattern during operation of the data processing system and predicting, from stored object access patterns from a like context, accesses to objects;
• and
• prefetching predicted objects and storing the predicted objects in cache memory.