SYSTEM AND METHODS FOR RAID WRITING AND ASYNCHRONOUS PARITY COMPUTATION

摘要

A computer storage management system for managing a first plurality of computer storage units operative to store data each including at least a second plurality of corresponding data portions, the system comprising a parity-based RAID writing and asynchronous parity computation manager operative to manage a stream of operations including writing operations and to asynchronously compute at least one parity, including, responsive to occurrence of at least one write operation in which an incoming value is to be written into an individual computer storage unit from among the computer storage units, depositing the incoming value in the individual storage unit, thereby to define an individual data portion stored therewithin, and in a pre-parity storage area and computing and storing a parity combining the incoming value with the values of those data portions, in the computer storage units other than the individual computer storage unit, which correspond to the individual data portion; and a post-loss parity computing data recovery manager operative to recover lost data including determining whether at least one parity of at least one data portion within the lost data is not current and, for at least one non-current parity, using information stored in the pre-parity storage area to generate, after the lost data has been lost, a current parity to replace the non-current parity and using the current parity to recover the lost data.