Browse Prior Art Database

Programming Tool to Locate Storage Not Deallocated Due to Errors

IP.com Disclosure Number: IPCOM000062239D
Original Publication Date: 1986-Oct-01
Included in the Prior Art Database: 2005-Mar-09
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Hammond, NT: AUTHOR

Abstract

In the operation of large computer systems, storage is regularly allocated to users by a storage management program. When a user is finished with a particular segment of storage, or when a user logs off of the system, the storage allocated is deallocated so that it can in turn be allocated to other users.

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Programming Tool to Locate Storage Not Deallocated Due to Errors

In the operation of large computer systems, storage is regularly allocated to users by a storage management program. When a user is finished with a particular segment of storage, or when a user logs off of the system, the storage allocated is deallocated so that it can in turn be allocated to other users.

Due to programming anomalies, or programming errors, segments of storage sometimes are not deallocated when they ar longer needed. Such segments are sometimes referred to as "lost segments". Lost segments can severely degrade the performance of a system and, in fact, if there are large numbers of such "lost segments" it can cause the system to abend.

When a segment of storage is allocated to a user, certain control information is appended at the end of the block of allocated storage. An advantage can be gained by adding a field to the control information which identifies the user I.D. which caused the particular storage to be allocated.

In normal operation, when a user logs off of the system all of the storage allocated to that user (other than special blocks such as spool blocks) is deallocated. If the control information in each segment includes an identification of the user for whom the block was allocated, it is possible to scan all of the allocated storage and determine if any of the storage is allocated to users that are no longer logged onto the system. such storage identified is storage tha...