Browse Prior Art Database

Suppressing Overreaction to Equipment Checks Errors

IP.com Disclosure Number: IPCOM000088384D
Original Publication Date: 1977-Jun-01
Included in the Prior Art Database: 2005-Mar-04
Document File: 2 page(s) / 26K

Publishing Venue

IBM

Related People

Blickenstaff, RL: AUTHOR [+3]

Abstract

In a mass storage system (MSS) having a mass storage controller (MSC), a mass storage facility (MSF) with a plurality of independently programmed and operating staging adaptors which may be integrated staging adaptors (INSA) with a staging store (SSF) consisting of DASD (direct access storage device) spindles, an equipment check, i.e., hardware failure, in one DASD spindle can involve a plurality of host programs because of the virtual addressing between a primary host (PH), other host (OH), and MSS. For example, one spindle of DASD in SSF may have 40 virtually addressed memory portions containing data operated upon by a larger number of programs in the various hosts. Hence, one equipment check could involve abnormal ending (ABEND) of 40 or more programs in the hosts.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 2

Suppressing Overreaction to Equipment Checks Errors

In a mass storage system (MSS) having a mass storage controller (MSC), a mass storage facility (MSF) with a plurality of independently programmed and operating staging adaptors which may be integrated staging adaptors (INSA) with a staging store (SSF) consisting of DASD (direct access storage device) spindles, an equipment check, i.e., hardware failure, in one DASD spindle can involve a plurality of host programs because of the virtual addressing between a primary host (PH), other host (OH), and MSS. For example, one spindle of DASD in SSF may have 40 virtually addressed memory portions containing data operated upon by a larger number of programs in the various hosts. Hence, one equipment check could involve abnormal ending (ABEND) of 40 or more programs in the hosts. In a data processing environment such a large number of ABENDs all caused by one equipment check (EQCHK) can greatly reduce the effectiveness of the data processing system, hence, increase computing cost. Accordingly, it is desired to suppress the effect of such an equipment check in a virtually addressed mass storage environment.

When INSA recognizes an equipment check signal termed EQCHK-1 from any of the DASDs, rather than sending such signal onto the host accessing the data from the given failing spindle, EQCHK-1 is blocked, and the spindle that is failing is reserved to MSC. This reservation prevents any of the hosts from accessing the failing...