Multi-Stage Prefetching to Exploit Long-Term Future Data Access Sequence Knowledge

摘要

A system and method for scheduling the pre-loading of long-term data predicted to be requested in future time epochs into a faster storage tier are disclosed. For each epoch into the future, which may be on the order of minutes or hours, data chunks which may be accessed are predicted. Intersections are taken between predicted data chunks, starting with the furthest predicted epoch in the future, ranging back to the next future epoch. These are then intersected with adjacent results, on up a hierarchy until an intersection is taken of all of the predicted epochs. Commands are generated to preload the data chunks predicted to have the most recurring accesses, and the predicted data chunks are pre-loaded into the cache. This proceeds down the load order until either the last predicted data set is pre-loaded or it is determined that the cache has run out of space.