Browse Prior Art Database

Record Caching

IP.com Disclosure Number: IPCOM000038757D
Original Publication Date: 1987-Mar-01
Included in the Prior Art Database: 2005-Feb-01

Publishing Venue

IBM

Related People

Authors:
Legvold, V Martin, G McCauley, J [+details]

Abstract

The requirement is to provide a caching environment that allows the user to access single records on a track as the basic mode of operation yet still allow full track operation to support the Dump/Restore operations that are needed as backup. A basic problem is to properly allocate space in the cache so that fragmentation does not occur. The cache is divided into full track buffers and from one to four different size record slots. The user specifies this division. A single record, that is not larger than the largest record slot, remains in the cache after it has been accessed. A record can be located by hashing through a single Scatter Index Table (SIT). Although there is a single SIT, each record size has its own Least Recently Used (LRU) chain.