VM (often: VM/CMS) is a family of IBM virtual machine operating systems used on IBM mainframes System/370, System/390, zSeries, System z and compatible
(z/VM or KVM on IBM Z). Microcode restricts IFLs from running "traditional" workloads, such as z/OS, but they are physically identical to other IBM Z processors
users the confidence to adopt new IBM systems fairly quickly. IBM's current mainframe operating systems, z/OS, z/VM, z/VSE, and z/TPF, are backward compatible
(later renamed IBM eServer pSeries, then IBM System p, and now IBM Power Systems). AIX Version 3, introduced in 1988, for the PS/2 and VM/370 systems, developed