About This Guide

This manual includes the following sections (each is a separate file):

The figure on the next page illustrates this organization pictorially.

Figure 1. Organization of this Manual

Figure i Organization of this Manual

References and Source Material

Much of the explanatory material in this book was taken from the following canons:

  • Lenoski, Daniel and Weber, Wolf-Dietrich. Scalable Shared-Memory Multiprocessing San Francisco: Morgan Kauffman, 1995.

  • Hennessy, John and Patterson David. Computer Architecture: A Quantitative Approach San Mateo, California: Morgan Kauffman, 1990

  • Schimmel, Curt. Unix Systems for Modern Architectures Menlo Park, California: Addison Wesley, 1994

James Laudon's System Specification and Cache Coherence Protocol Specification provided a wealth of information. Both are internal Silicon Graphics® documents.

The following information was also relevant:

  • Kourosh Gharachorloo, Daniel Lenoski, James Laudon, Phillip Gibbons, Anoop Gupta, and John Hennessy. Memory Consistency and Event Ordering in Scalable Shared-Memory Multiprocessors. Proceedings of the 17th International Symposium on Computer Architecture, pages 15-26, May 1990.


  • Kourosh Gharachorloo, Anoop Gupta, and John Hennessy. Revision to Memory Consistency and Event Ordering in Scalable Shared-Memory Multiprocessors. Technical Report CSL-TR-93-568, Computer Systems Laboratory, Stanford University, April 1993.


  • Daniel Lenoski, James Laudon, Truman Joe, David Nakahira, Luis Stevens, Anoop Gupta, and John Hennessy. The DASH Prototype: Implementation and Performance. In Proceedings of the 19th International Symposium on Computer Architecture, pages 92-103, Gold Coast, Australia, May 1992.


Thanks also to Ben Passarelli, Rick Bahr, Rich Altmaier, Ben Fathi, Ed Reidenbach, Rob Warnock, Jim “Positive-ECL” Smith, Sam Sengupta, Dave Parry, Robert A. dePeyster, Mike Galles, and Luis Stevens.

Finally, thanks to John Mashey ([email protected]) for making himself iteratively available during various emergencies.

Typographical Conventions


  • is used for emphasis

  • is used for bits, fields, and registers important from a software perspective (for instance, address bits used by software, programmable registers, etc.)

Bold Text

  • represents a term that is being defined

  • is used for bits and fields which are important from a hardware perspective (for instance signals on the backplane, or register bits which are not programmable but accessible only to hardware)

For More information

The following documents provide additional information about the Origin family of systems:

Origin and Onyx2 Theory of Operations Manual, part number 007-3439-nnn

IRIX Device Driver Programmer's Guide, part number 007-0911-nnn

Origin2000 Deskside Server Owner's Guide, part number 007-3453-nnn

Origin2000 Rackmount Owner's Guide, part number 007-3456-nnn

Onyx2 Deskside Workstation Owner's Guide, part number 007-3454-nnn

Origin200 Owner's Guide, part number 007-3415-nnn