A shared system memory, such as a cache, buffers Input/Output (I/O) requests between one or more host computers and one or more data storage servers or devices. The cache may be configured to operate natively as a least-recently-used (LRU)-only cache and may be optimized for random data accesses. Data buffered by the cache may be part of a sequential data stream for which prefetching data is desirable. A remote prefetch module is provided between the cache and the host to conduct prefetching wit...

A method for calculating a block cache size for a host process or application on a computer based at least upon virtual memory page evictions and/or virtual memory page reclamations for the computer. A virtual memory page eviction is the act of removing the contents of a physical memory page for the purpose of loading it with the contents of another virtual memory page. A virtual memory page reclamation is the return of a page to a working set that was previously removed by the operating system ...

A disk drive is disclosed for executing a program comprising a plurality of instructions. The disk drive comprises a primary memory for storing the instructions, and a cache memory for caching the instructions. The cache management is enhanced by not re-filling the cache due to accessing a non-sequential immediate operand.

A method and apparatus for a microprocessor with a cache that has the advantages given by a victim cache without physically having a victim cache is disclosed. In one embodiment, a victim flag may be associated with each way in a set. At eviction time, the way whose victim flag is true may be evicted. However, the victim flag may be reset to false if a superceding request arrives for the cache line in that way. Another cache line in another way may then have its victim flag made true.

A storage provisioning policy is created by specifying storage heuristics for storage attributes using storage heuristic metadata. Storage attributes characterize a storage device and storage heuristic metadata describe how to specify a storage heuristic. Using the storage heuristic metadata, storage heuristics are defined to express a rule or constraint as a function of a storage attribute. In addition, the storage provisioning policy may also specify mapping rules for exporting the storage to ...

A flash memory system is disclosed. The flash memory system includes a flash memory comprising more than one physical block and more than one page, where each page can be in an enabled state, a blank state or a disabled state. In use, a merge control section reads data on an enabled page from a predetermined physical block using a read section, and writes the data onto a blank page using a write section, thereby copying the data on the enabled page onto the blank page. A merge control section th...

A method and processor system that substantially enhances the store gathering capabilities of a store queue entry to enable gathering of a maximum number of proximate-in-time store operations before the entry is selected for dispatch. A counter is provided for each entry to track a time since a last gather to the entry. When a new gather does not occur before the counter reaches a threshold saturation point, the entry is signaled ready for dispatch. By defining an optimum threshold saturation po...

A memory architecture with a multiple cache coherency includes at least one processor with a storage area in communication with a cache memory. A main bus transmits and receives data to and from the cache memory and the processor. A coherency control in communication with the cache memory and the processor is configured to determine an existence or location of data in the cache memory or the storage area in response to a data request from the main bus. The coherency control dispatches an existen...

A storage device in a set associative system includes N-pieces (N is an integer of 2 or larger) of ways each having a plurality of entries containing at least replace flags and predetermined data, an acquisition unit acquiring the replace flags contained in the entries specified by the same address from the N-pieces of ways, and a selection unit selecting a replace target way on the basis of the replace flags acquired by the acquisition unit.

A digital data processor comprising a stack storage having a plurality of locations classified into two or more banks, and a stack pointer circuit pointing to one or more stack banks of the stack storage. The stack pointer circuit operates in response to decoding signals from an instruction decoder which decodes a current instruction to determine whether a one-word or a multi-word stack operation is desired.