Browse Prior Art Database

DASD Array Made of Partial Good Drives and Shared Drive

IP.com Disclosure Number: IPCOM000115980D
Original Publication Date: 1995-Jul-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 2 page(s) / 41K

Publishing Venue

IBM

Related People

Eldridge, JW: AUTHOR [+2]

Abstract

DASD Array is made DASD units with known defects. Additional units are added to the array to compensate for loss of capacity due to defects. Added capacity is shared across parity domains.

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DASD Array Made of Partial Good Drives and Shared Drive

      DASD Array is made DASD units with known defects.  Additional
units are added to the array to compensate for loss of capacity due
to defects.  Added capacity is shared across parity domains.

      DASD Array can be constructed from DASD units with defects with
a net loss in capacity.  Disclosed is the use of added DASD units to
compensate for the capacity loss.  These units can be shared across
parity domains as illustrated in Fig. 1A.

      In a DASD Array built of full capacity devices, one or more
devices may suffer defects over the life of the array.  Disclosed is
the use of a spare device to compensate for the loss in capacity due
to these isolated defects.  These spare devices may be shared across
parity domains.  Fig. 1B is also applicable to illustrate this
mechanism.