Fault tolerant data processing system

US5325517A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Ernest D. Baker · Boca Raton, US
• John Dinwiddie · North Palm Beach, US
• Lonnie E. Grice · Boca Raton, US
• James M. Joyce · Boca Raton, US
• John M. Loffredo · Deerfield Beach, US
• Kenneth R. Sanderson · West Palm Beach, US
• Gustavo A. Suarez · Boca Raton, US

Key dates

• Filing date: May 17, 1989
• Grant date: Jun 28, 1994
• Expiry date: May 17, 2009

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F11/20
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

The functions of two virtual operating systems (e.g., S/370 VM, VSE or IX370 and S/88 OS) are merged into one physical system. Partner pairs of S/88 processors run the S/88 OS and handle the fault tolerant and single system image aspects of the system. One or more partner pairs of S/370 processors are coupled to corresponding S/88 processors directly and through the S/88 bus. Each S/370 processor is allocated from 1 to 16 megabytes of contiguous storage from the S/88 main storage. Each S/370 virtual operating system thinks its memory allocation starts at address 0, and it manages its memory through normal S/370 dynamic memory allocation and paging techniques. The S/370 is limit checked to prevent the S/370 from accessing S/88 memory space. The S/88 Operating System is the master over all system hardware and I/O devices. The S/88 processors access the S/370 address space in direct response to a S/88 application program so that the S/88 may move I/O data into the S/370 I/O buffers and process the S/370 I/O operations. The S/88 and S/370 peer processor pairs execute their respective Operating Systems in a single system environment without significant rewriting of either operating syst…