Overview

IBM® Z platforms are the latest generation in IBM's family of mainframe offerings. IBM's mainframes have a long legacy since being first produced over 50 years ago. The system technology has continued to expand and evolve, enabling IBM mainframe releases to continue to offer capabilities and features that enterprise customers require.

• The IBM Z family maintains full backward compatibility. In effect, current systems are the direct, lineal descendants of System/360, announced in 1964, and the System/370 from the 1970s. Many applications written for these systems can still run unmodified on the newest IBM Z system over five decades later.¹, ²

Over several decades, as more and more software stacks and operating system choices have been added to the IBM Z software catalog (while maintaining full backward compatibility), the IBM mainframe has become a virtual Swiss Army knife in terms of all the things it can do.

Figure 1 shows an overview of the IBM Z integrated virtualization capabilities. PR/SM allows the system resources (CPUs, memory, I/O adapters) to be dedicated or shared across up to 85 logical partitions. Each of the logical partitions (LPARs) can be installed with a variety of target operating systems. z/OS® and z/VM® have been available for a long time, and Linux® has also been supported for a number of years.

• Using the combination of KVM virtualization and IBM Z and LinuxONE, you have the performance and flexibility to address the requirements of multiple, differing Linux workloads. KVM’s open source virtualization on IBM Z and LinuxONE allows businesses to reduce costs by deploying fewer systems to run more workloads, sharing resources, and improving service levels to meet demand.³,⁴