SAP SE
Fair prefetching in hybrid column stores

Abstract:

Disclosed herein are system, method, and computer program product embodiments for performing fair prefetching. An embodiment operates by splitting a data vector into a first subrange and a second subrange. The embodiment performs a first chance prefetch operation on the first subrange based on a fixed number of pages, thereby loading a set of pages of the first subrange into a main memory. The embodiment performs the first chance prefetch operation on the second subrange based on the fixed number of pages, thereby loading a first set of pages of the second subrange into the main memory. The embodiment performs a second chance prefetch operation on the second subrange based on the performing the first chance prefetch operation on the second subrange, thereby loading a second set of pages of the second subrange into the main memory. The embodiment then executes the query.