Patent ID: 8006139
Filing Date: 2011-08-23
Classification: G06F

Abstract:
1. A degeneration control device that controls degeneration of a cache having a plurality of ways based on an error that occurs in response to an access request, comprising: a cache line degeneration information memory unit, which stores cache line degeneration information that indicates whether a cache line constituting each of the plurality of ways is degenerated; a degeneration control unit, which writes, when an error that occurs in response to the access request causes a predetermined condition to be met, cache line degeneration information that indicates a predetermined cache line where the error occurs is degenerated in the cache line degeneration information memory unit; and a way selection unit, which selects, when data corresponding to the access request is not stored in the cache, a cache line where the data corresponding to the access request is to be cached, by referring to at least one of the cache line degeneration information and way degeneration information stored in the cache line degeneration information memory unit, the way selection unit selecting, when all cache lines to be selected as areas where the data is cached are degenerated, a cache line where data corresponding to the access request is to be cached, from cache lines constituting a way which is not degenerated, by referring to the cache line degeneration information and by referring not to the way degeneration information, and preferentially validating back the selected cache line from the degeneration.