Abstract: For use in a storage area network (SAN), a virtualization layer including at least one virtual engine having a respective local cache and a secondary cache layer, wherein the secondary cache layer includes the local caches coupled together, the local caches individually including a first cache layer, and at least one of a data transfer command and data corresponding to the transfer command are multicast to the secondary cache layer through an interconnection bus, the interconnection bus coupling the at least one virtual engine and at least one physical storage device.

Abstract: A method, system and apparatus for improving the useful life of non-volatile memory devices such as flash memory. The present wear-leveling technique advantageously improves the overall useful life of a flash memory device by strategically moving inactive data (data that has been infrequently modified in the recent past) to the memory blocks that have experienced the most wear since the device began operation and by strategically moving active data to the memory blocks that have experienced the least wear. In order to efficiently process and track data activity and block wear, vectors of block-descriptor pointers are maintained. One vector is sorted in decreasing order of overall block erase/write activity (block-wear indicator), whereas the other vector is sorted in increasing order of the number of times a block has been erased since the last wear-leveling event occurred (activity indicator for the data stored in the block).