Patent ID: 9003127
Filing Date: 2015-04-07
Classification: G06F

Abstract:
1. A computer implemented method for storing data to a system memory, the method comprising: initializing an internal congruence class register; accessing a plurality of directory entries of a cache directory of a cache having a plurality of directory entries in a current congruence class of the cache directory that corresponds to the internal congruence class register, the accessing of the plurality of directory entries being given a lower priority than other cache operations in the cache; determining that a specific directory entry of the plurality of directory entries in the cache directory has a change line state that indicates that the specific directory entry is modified; performing a store operation to send a copy of cache data associated with the specific directory entry to the system memory as part of a cache management function; updating the specific directory entry to indicate the change line state is unmodified; incrementing the internal congruence class register; and initiating an access to a next plurality of directory entries in a next congruence class of the cache directory based on the incremented internal congruence class register; further comprising performing the store operation to send the copy of the cache data associated with the specific directory entry to the system memory based on an ownership tag of the specific directory entry being set to an unowned state.