Overview

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

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

Over several decades, as more and more software stacks and operating system choices have been added to the IBM Z platforms software catalog and 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. High-level Overview of the IBM Z Mainframe
High-level overview of the IBM Z mainframe
Figure 1 provides a high-level picture of the IBM Z integrated virtualization capabilities.
  • PR/SM allows the system resources (CPUs, memory, IO adapters) to be dedicated or shared across up to 60 logical partitions.
  • Each of the logical partitions can be installed with a variety of target operating systems.

The z/OS® and z/VM® operating systems have been available for a long time. For a number of years, the choice of running the Linux® operating system has been supported. Now the support for the hypervisor KVM has been included to provide open-source virtualization capabilities within a logical partition on IBM Z and IBM LinuxONE platforms.

Using the combination of KVM virtualization and IBM Z and IBM 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 allow businesses to reduce costs by deploying fewer systems to run more workloads, sharing resources, and improving service levels to meet demand.2

For more information about the LinuxONE and KVM running on IBM Z, visit (https://www.ibm.com/docs/en/linux-on-systems?topic=virtualization-kvm).