Abstract:
For use with a computer system having an intelligent mass storage disk array subsystem, including a microprocessor controller, a method for the distribution of data within the disk array based upon logical commands issued by the computer system. The disk controller reads a logical command and translates the commands into multiple drive specific commands, including drive physical parameter information such as head, sector and cylinder selection. The calculation of these physical parameters is based upon a number of factors including the operating system installed in the computer system, the type of interleave scheme, if any, specified by the computer system configuration, and disk. specific parameters. The physical drive requests are then placed in a queue and executed by the microprocessor controller. The method also encompasses a method for creating a disk array configuration to be loaded on all disks within the array based on existing valid disk array information and configuration information maintained by the computer system.
Abstract:
An array of disk drives (50,60) organized as a data storage system including n parity drives (60) forming n parity chains (A-D) where each parity drive maintains the parity bits of a different combination of data drives and each data drive (50) is included in at least two parity chains, and where no two data drives are associated with the same combination of parity chains. The present error correcting code (ECC) technique requires only n parity drives for up to 2n-n-1 data drives for a maximum total of 2n-1 disk drives. Each data drive is included in two or more parity chains and each parity chain is unique. The n parity drives are taken two at a time, then three at a time, and so on up to n at a time, each combination being unique, until all of the data drives are associated with parity chains. The ECC technique is implemented using a disk controller (22) which is coupled to the array of disk drives and constantly maintains the parity information on the parity drives. The disk controller selects appropriate parity chains to reconstruct the data of any two data drives that fail, and also performs the reconstruction onto replacement disk drives (70). Data striping or distribution of the data and parity information on the disk drives further increases the performance of a disk array using the present ECC technique.
Abstract:
An array of disk drives (50,60) organized as a data storage system including n parity drives (60) forming n parity chains (A-D) where each parity drive maintains the parity bits of a different combination of data drives and each data drive (50) is included in at least two parity chains, and where no two data drives are associated with the same combination of parity chains. The present error correcting code (ECC) technique requires only n parity drives for up to 2n-n-1 data drives for a maximum total of 2n-1 disk drives. Each data drive is included in two or more parity chains and each parity chain is unique. The n parity drives are taken two at a time, then three at a time, and so on up to n at a time, each combination being unique, until all of the data drives are associated with parity chains. The ECC technique is implemented using a disk controller (22) which is coupled to the array of disk drives and constantly maintains the parity information on the parity drives. The disk controller selects appropriate parity chains to reconstruct the data of any two data drives that fail, and also performs the reconstruction onto replacement disk drives (70). Data striping or distribution of the data and parity information on the disk drives further increases the performance of a disk array using the present ECC technique.
Abstract:
For use with a computer system having an intelligent mass storage disk array subsystem, including a microprocessor controller, a method for the distribution of data within the disk array based upon logical commands issued by the computer system. The disk controller reads a logical command and translates the commands into multiple drive specific commands, including drive physical parameter information such as head, sector and cylinder selection. The calculation of these physical parameters is based upon a number of factors including the operating system installed in the computer system, the type of interleave scheme, if any, specified by the computer system configuration, and disk. specific parameters. The physical drive requests are then placed in a queue and executed by the microprocessor controller. The method also encompasses a method for creating a disk array configuration to be loaded on all disks within the array based on existing valid disk array information and configuration information maintained by the computer system.