1. A computer storage system, comprising: a plurality of disk drives for storing parity groups, each parity group comprising storage blocks, said storage blocks comprising one or more data blocks and a parity block associated with said one or more data blocks, each of said storage blocks stored on a separate disk drive such that no two storage blocks from a given parity group reside on the same disk drive, wherein file system metadata comprises information to describe the data blocks in one or more parity groups.