Cache allocation mechanism for saving multiple elected unworthy members via substitute victimization and imputed worthiness of multiple substitute victim members

摘要

A method and apparatus in a data processing system for protecting against displacement of two types of cache lines using a least recently used cache management process. A first member in a class of cache lines is selected as a first substitute victim. The first substitute victim is unselectable by the least recently used cache management process, and the second substitute victim is associated with a selected member in the class of cache lines. A second member in the class of cache lines is selected as a second substitute victim. The second victim is unselectable by the least recently used cache management process, and the second substitute victim is associated with the selected member in the class of cache lines. One of the first or second substitute victims are replaced in response to a selection of the selected member as a victim when a cache miss occurs, wherein the selected member remains in the class of cache lines.