Browse Prior Art Database

Dynamic Reorganization of Storage Allocation for Enhancing Performance

IP.com Disclosure Number: IPCOM000040867D
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Brady, JT: AUTHOR

Abstract

In a disk storage device wherein access is a function of seek distance, a controller periodically moves data most frequently accessed to that portion of the disk surface adding shortest access time. In one embodiment, this portion of the disk is the outer track for enabling access from the outer periphery while in fixed spindle disk, this portion is radially tensile portion.

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Dynamic Reorganization of Storage Allocation for Enhancing Performance

In a disk storage device wherein access is a function of seek distance, a controller periodically moves data most frequently accessed to that portion of the disk surface adding shortest access time. In one embodiment, this portion of the disk is the outer track for enabling access from the outer periphery while in fixed spindle disk, this portion is radially tensile portion.

To achieve the operation of the invention, a layer of indirection is provided at the cylinder level of the disk storage device. The cylinder is of arbitrary size dependent upon the physical characteristics of the disk device. Cylinders also treated as a logical construct. Each logical cylinder is self- identifying by placing the cylinder data which indicates the logical cylinder address. In a device controller, a map of logical cylinders of physical cylinders is maintained. Associated with the map is a table for each logical cylinder that stores dynamic usage information for that given cylinder. This usage information is the reference frequency for the cylinder. Device controller is programmed to periodically examine the dynamic usage information to determine if the cylinder has become more active. If that cylinder becomes more active, then its informational contents are copied to a preferred area on the disk that is reserved for high activity. This area is dynamic and the size depends on the short-term characteristics of...