Curiosity about computing's future can be found in its past: The mighty Mainframe (MF) lives again.
Quick quiz. What do Mainframes and virtualization have to do with each other? Give up? In a single word: Everything. It may surprise you to know that virtualization existed on Mainframes for almost 3 decades before it existed on any other platform. As I was researching a new virtualization project involving IBM System z, z/VM, and Linux, I realized that we’ve come full circle in computing — from Mainframes and dumb terminals to the wonderful world of mid-range computers, departmental servers, and heavy desktops back to those dinosaur days of yesteryear of Mainframes and dumb terminals. Could it be true that we are returning to our roots as mere users on behemoth systems where an administrator allocates a virtual resource slice to us instead of a complete physical system with which to work? The answer is yes. The answer is also no.
It’s true that Mainframe computing is making a comeback in the virtualization space. It’s also true that, for VDI (Virtual Desktop Infrastructure), Mainframes make a lot of sense. Mainframes provide security, stability, a choice of either pooled or dedicated resources, and 40-year history of success that is unmatched by any other existing technology. They’re also a wise choice for Cloud Computing — a natural for Mainframe scalability and dynamic resource allocation.
Cloud Computing on a Mainframe? Yes, and though this be madness, yet there is method in it — the Mainframe/Cloud Computing paradigm have much in common. Consider the following list of attributes.
- Users lease computing time and resources.
- Users neither know, nor care, where their data is kept.
- Security is a primary concern.
- Server and resource provisioning is dynamic
- User spaces are logically separated from each other.
- Computing resources are dynamic.
- 100% Availability
- Remote access is operating system independent.
Are the items in the list describing Mainframe computing or Cloud Computing? If you said both, congratulations, you are correct. Cloud Computing sounds suspiciously like Mainframe computing doesn’t it? It sounds that way to old Mainframers who claim that grid computing, Cloud Computing, or whatever you want to call it, is not some new-fangled technology, but has been around longer than most of you. They also claim that those old school Mainframes are better at the job than the hottest googolplexed x86 processor-based machines will ever be. So what else makes the System z Mainframe desirable as a Cloud Computing platform? z/VM is the most mature type of virtualization, as I’ve already stated, with over 40 years of proven success. Coupled with its history and experience, z/VM is a Type-1 hypervisor much like Xen, VMware’s ESX Server, and Virtual Iron, which aligns it with other current virtualization technologies.
Where’s the downside to using Mainframes for Cloud Computing — or the no part of the answer to the question I asked in the first paragraph? Mainframes still send your bank account into the red. If you duplicated a Mainframe’s processing power in x86 architecture, you would spend at least twice as much on the Mainframe. For your efforts, you’d receive more processing power from the x86 Supercomputer, however there’s more to Cloud-based computing than pure processing power. Mainframes possess superior I/O, which is an often-overlooked aspect of virtualization — especially when considering database virtualization or providing an acceptable user experience for virtualized Desktops.
Does this all mean that you should start looking into the purchase of a Mainframe for your company? Certainly not. It does mean, though, that Cloud Computing vendors who use them, or foresee using them for their services, will be able to meet any resistance to their services by just stating the facts about Mainframe computing.
Since Mainframes aren’t new, or even perceived as new, they don’t garner the same hype that surrounds emerging technologies, there are no buzzwords or trade show excitement following them, and most people think they’re ancient history. They still exist. They’re just there — as they’ve always been — working.
Kenneth Hess is a Linux evangelist and freelance technical writer on a variety of open source topics including Linux, SQL, databases, and web services. Ken can be reached via his website at http://www.kenhess.com
. Practical Virtualization Solutions by Kenneth Hess and Amy Newman is available now.