Abstract: The present invention carries out cache management in such a manner that the management region required for cache management does not increase, and neither does the performance decline. It is possible to combine use of both a hierarchical directory method and a hash directory method, in order to manage cache data. In a hierarchical directory method, the desired data is retrieved by referring to respective tables T1 to T7, in succession. In a hash directory method, the desired data is reached by referring to a hash table T10 and tables T4 to T7. Access conflicts between the respective methods are avoided by using the EDEV number and a portion of the VDEV number for a hash key. By combining use of both of these methods, it is possible to respond to cases where the storage capacity of the storage system has been increased, without having to raise the management region, and without causing a decline in performance.

Abstract: In some embodiments, a storage medium comprises application software that performs one or more operations and that directly facilitates the conversion of a virtual memory address to a physical memory address. The application software comprises instructions that initialize an application data structure (e.g., an object or array) usable by the application software to facilitate the conversion of memory addresses and also comprises instructions that store pointers to the virtual memory addresses to be converted. In other embodiments, a system comprising a secure and non-secure memory subsystem is disclosed. Before execution of an application stored in the secure sub-system, a list of pointers to parameters contained in virtual memory is created. The virtual memory addresses referenced by the pointers in the list are converted to pointers to physical memory addresses before execution of the application.