The Business Value of DB2 UDB for z/OS

Chapter 2. The evolution of DB2 for z/OS 33

Intelligent Resource Director and Workload Manager continuously track activity

and direct work and resources in a manner which ensures that business

service-level agreements are met. Workload throughput is maximized and “white

space” is minimized.

This environment is mature and sophisticated. Extensive autonomic features of

the operating system ensure that resources are continually monitored. This is

about the server being up. It is about the application and the data and the

connection to disk being up. This environment offers extreme availability. New

high priority work can be added and immediately serviced adequately at the

expense of lowest priority workloads. This is truly unique in the industry. It is the

substance that ensures data is available on demand. You can learn more in 3.9,

“WorkLoad Manager, Intelligent Resource Director, and VIPA” on page 63.

2.2.2 Near-linear scalability

DB2 in a Parallel Sysplex configuration offers tremendous near-linear scalability.

You can scale vertically within a server or horizontally across the group. Within

the zSeries architecture, the cost of adding a member to an existing group is

minor. For more information about sysplex timers and the coupling facility, both

key components of zSeries, see 3.2, “Parallel Sysplex and data sharing” on

page 43, and 3.2.6, “Summary” on page 48.

2.2.3 Preservation of investment

IBM works hard a preserving the investment that you have in you application

software and database structures. See 3.11, “zSeries 990” on page 75.

Backward compatibility

When you upgrade from one version to another, the design strategy is to ensure

that existing code executes successfully without any changes. The few

necessary incompatibilities that exist are highlighted early. IBM identifies and

describes these in a timely manner allowing you to proactively research and

adjust where necessary. Where practical, IBM provides automated scripts to

locate incompatibilities.

Proactive notification

IBM has provided ample notification of upcoming changes which demand

change in database structure or application coding. For example the deprecation

of type 1 indexes was announced at least two versions before it took effect.

Similarly there have been numerous announcements about the future demise of

private protocol. In both cases, the alternatives, type 2 indexes and DRDA

protocol, enabled a much higher level of usability and performance.