System and methods for RAID writing and asynchronous parity computation

• Main Author: ATZMONY YEDIDIA
• Format: Patent
• Language: English
• Published: 27.01.2015
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; PHYSICS

A computer storage management system for managing a first plurality of data storage units, the system including: (a) an asynchronous parity computation manager which, responsive to a write operation in which an incoming data portion is to be written into an individual storage unit from among the storage units, deposits the incoming value in the individual storage unit and stores a copy of the data element in a pre-parity storage area, and wherein asynchronously with depositing the incoming value in the individual storage unit, the asynchronous parity computation manager is operative to compute parity data corresponding to the incoming data portion and to other data portions which are associated with the incoming data portion and to store the parity data; and (b) a post-loss data recovery manager operative to recover lost data including determining whether at least one parity value associated with at least one data portion within said 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 said lost data has been lost, a current parity to replace said non-current parity and using said current parity to recover said lost data.