Patent ID: 8443137
Filing Date: 2013-05-14
Classification: G06F

Abstract:
1. A storage system comprising: a) a plurality of disk units adapted to store data at respective ranges of logical block addresses (LBAs), said addresses constituting an entire address space, b) a storage control grid operatively connected to the plurality of disk units and comprising a plurality of data servers; wherein each certain LBA is assigned to at least two data servers: a first data server configured to have a primary responsibility for handling requests directed to at least said certain LBA and to generate a primary cache object in response to a request directed to at least saidcertain LBA, and a second data server configured to have a secondary responsibility for handling requests directed to at least said certain LBAand to overtake the primary responsibility for handling requests directed to at least said certain LBA if the primary server fails; and wherein the storage system is further configured, in response to said request directed to at least said certain LBA, to generate a redundancy object in the second data server, said redundancy object to be deleted upon successful permanent storing by the first data server of data and/or metadata corresponding to said request, and to be used by the second data server for permanent storing said data and/or metadata when overtaking respective responsibility, wherein said redundancy object is further configured to be handled in a searchable data structure with no need to be incorporated into cache-object control procedures and/or dirty data destaging procedures of the second server before overtaking the primary responsibility, and wherein said redundancy object is derivation of the primary cache object and need to be reconstructed in order to enable overtaking the responsibility.