DASD Cache for File Subsystem
Original Publication Date: 1984-Nov-01
Included in the Prior Art Database: 2005-Feb-05
This article describes a cache that is designed as a separate I/O device within the file subsystem. While maintaining the performance advantages of a cache that is integrated into the direct-access storage device (DASD) adapter, this approach is more flexible, provides for expanded applications, supports indirect device-to-device transfer, and can be shared by all devices in the file subsystem. Since it can be shared by all of the devices in the file subsystem, the cost is reduced. The expanded applications make it possible to tailor the usage to the individual customer, thus maximizing the performance for a broader range of applications. DASD cache is traditionally used in a system to enhance performance. The file management code attempts to anticipate the data requests from the system.