IBM eServer zSeries 990 Technical Guide

© Copyright IBM Corp. 2003, 2004. All rights reserved. 1

Chapter 1. zSeries 990 overview

This chapter gives a high-level view of the IBM Eserver zSeries 990. All the topics

mentioned in this chapter are discussed in greater detail later in this book.

The legacy of zSeries goes back more than 40 years. Actually, on April 7th, 2004, it was 40

years ago that IBM introduced its S/360™. Since then, mainframes have followed a path of

innovation with a focus on evolution to help protect investments made through the years.

The proliferation of servers in the last decade or so has increased complexity in IT

management and operations and decreased the overall efficiency of resource use. On top of

this came the need for business solutions to support business pressures on demand, which

requires an on demand operating environment capable of being supportive, adaptive, and

responsive to on demand business objectives and offering infrastructure simplification with

the values of the mainframe technology as set forward with the zSeries 990.

The zSeries 990 is designed for any enterprise that needs the qualities of service required to

sustain and expand their on demand computing environment. Customers requiring the ability

to meet mission-critical requirements that include unexpected demands, high numbers of

transactions, a heterogeneous application environment, and the ability to consolidate a

number of servers will find the z990 an attractive solution since it leverages the current

application portfolio with Linux and z/OS®, and simplifies the operation and management of

business applications by consolidating both Linux and mainframe applications onto the same

platform.

Customers with 9672s and z900s should consider using this server to consolidate servers

and workloads, add capacity, or expand their Linux workloads in a more cost-effective

manner. The increased capacity, bandwidth, number of channels, and logical partitions

provide customers with the ability to reduce costs, while positioning them for future

expansion.

The z990 is based on the proven IBM z/Architecture™, which was first introduced with the

z900 family of servers. It is the continuation of the zSeries z/Architecture evolution and

extends key platform characteristics with enhanced dynamic and flexible resource

management, scalability, and partitioning of predictable and unpredictable workload

environments. Additionally, the z990 availability, clustering, and Qualities of Service are built

on the superior foundation of the current zSeries technologies.

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2 IBM ^ zSeries 990 Technical Guide

The z990 servers can be configured in numerous ways to offer outstanding flexibility in the

deployment of e-business on demand™ solutions. Each z990 server can operate

independently, or as part of a Parallel Sysplex® cluster of servers. In addition to z/OS, the

z990 can host tens to hundreds of Linux images running identical or different applications in

parallel, based on z/VM® virtualization technology.

The z990 supports a high scalable standard of performance and integration by expanding on

the balanced system approach of the IBM z/Architecture. It is designed to eliminate

bottlenecks through its virtually unlimited 64-bit addressing capability, providing plenty of

“headroom” for unpredictable growth in enterprise applications.

The z990 provides a significant increase in system scalability and opportunity for server

consolidation by providing a “multi-book” system structure that supports configurations of one

to four books. Each book consists of 12 Processor Units (PUs) and associated memory, for a

maximum of 48 processors in a four-book system. All books are interconnected with a very

high-speed internal communications links via the L2 cache, which allows the system to be

operated and controlled by the PR/SM™ facility as a symmetrical, memory-coherent

multiprocessor. The logical partitioning facility provides the ability to configure and operate as

many as 30 logical partitions, which have processors, memory, and I/O resources assigned

from any of the installed books.

The chart in Figure 1-1 shows growth improvements along all axes. While some of the

previous generation of servers have grown more along one axis for a given family, later

families focus on the other axes. Now, with the z990, the balanced design achieves

improvement equally along all four axes.

Figure 1-1 Balanced system design

External I/O or STI bandwidth only (Internal Coupling Channels and HiperSockets not included).

zSeries MCM internal bandwidth is 500 GB/sec. Memory bandwidth not included (not a system constraint) .

0.83 ns

96 GBps

256 GB

32-way

1.3 ns

24 GBps

16-way

64 GB

zSeries z900

Generation 6

Generation 5

Generation 4

zSeries z9XX

System I/O Bandwidth

CPUs

Cycle

Time

Memory