Browse Prior Art Database

DASD Space Allocation

IP.com Disclosure Number: IPCOM000089222D
Original Publication Date: 1977-Oct-01
Included in the Prior Art Database: 2005-Mar-04
Document File: 2 page(s) / 32K

Publishing Venue

IBM

Related People

Arnold, RF: AUTHOR [+3]

Abstract

A front/backing store is efficiently located on a single direct-access storage device (DASD) spindle.

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DASD Space Allocation

A front/backing store is efficiently located on a single direct-access storage device (DASD) spindle.

An actuator moves a head radially of a record storage disk. Because of the construction of the actuator, the response time for moving from one concentric track to a second concentric track is less in area B than in area A or C. Accordingly, most-used data is allocated to area B (front store) by the control computer for the benefit of the host. As the most-used data is defined by the host, area B can be radially expanded or contracted, areas A and C are considered a backing store for less-used data.

In addition to the three illustrated dynamic and logically determined zones, five or more zones may be employed.

The principle of placing most-used data in the area of the storage apparatus most easily accessed can be applied to a stack of co-rotating disks accessed by a single transducer. In such apparatus, the central disks contain the most used data. In other actuator configurations, other disks may be selected to contain most used data.

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