The cloud world inherited some concepts from the mainframe
world that came before it. The consumption-based pricing model, Linux virtual
machines, and multi-tenancy came from that previous mainframe generation. NASA
got rid of its mainframes, but these massive machines can still be found in
many large organizations.

In the age of cloud IT, aren’t mainframes irrelevant?
Why won’t the mainframe die?

David Hodgson, SVP at CA Technologies, Inc., described the role of mainframes today. CA started 38 years ago as a mainframe software supplier and still
does mainframe work. In my interview with Hodgson, he said, “The mainframe business to CA is still just
over 50% of our revenue.” CA Technologies is not a small company–it’s in the
Fortune 500, has billions of dollars in revenue, and employs many thousands of

What is a mainframe computer?

A mainframe computer is a type of big, powerful, expensive, and reliable computer that has been around for decades–IBM announced the System/360
50 years ago. A lot of the applications running on these machines were written
a programming language that’s just as old as the mainframes.

Several vendors sell mainframes today, but “mainframe
environment” pretty much means IBM zSeries machines. Hodgson said, “the old
established mainframe environment operating system is called z/OS. Most of the historic financial
processing is on z/OS.

“You’ve got this funny mix of applications that are years
old and written in COBOL. The storage side of things really hasn’t changed much
over the years… and it’s probably one of the more expensive aspects of owning a

This is not a machine built for ordinary workloads–a mainframe
runs big jobs, such as the managing the databases of an insurance company, the
scientific research of a national government, and the credit card transactions
of a bank. Many people have never even seen a mainframe.

The mainframe is

Who wants to work with mainframes? Surely, coders want to
conquer the world with Python, APIs, and web services. They don’t want to work
with old CICS
programs. System administrators want to build distributed computing systems
with cloud building blocks that are fault tolerant and highly scalable. Finance
officers want to rent cheap commodity hardware, not soak up their budget with a high-end expensive kit.

In fact, the mainframe is already dead, several times over.
Its death has been reported as the outcome of every new disruptive technology
to sweep the IT world. The mainframe was killed off by the desktop PC
revolution. And again by the client-server revolution. And now by the cloud
computing revolution, where massive quantities of CPU, storage, and memory are
instantly available for anyone to rent. 

If mainframes are old technology and basically dead, then
why are they still so central to so many enterprises?

The mainframe is not

Hodgson said the mainframe is still “massive in the
industry. Despite the predictions and rumours, it’s really not going away.
While some of the smaller customers have dropped off, all of the bigger
customers are growing their workloads on the mainframe.”

There are two sides to why the mainframe market is still
going strong. One is lock-in–an old business-critical application running on
a mainframe, with many years of business logic built into it, costs a fortune
to migrate elsewhere.

The other is the mainframe’s relevance in a modern hybrid
cloud architecture, running VMs on-premise and storing petabytes of data. Hodgson
said the mainframe “has evolved a lot over the years. You can run Linux on the
mainframe. We’re leveraging Linux
to do a VMware-like cloud environment–essentially a private cloud–on the

Hodgson talked about modern cloud providers. “A lot of what
these big providers are doing is really trying to recreate the mainframe by
hashing together a lot of servers.” A private cloud made from many commodity
boxes–one that can provide, say, 5,000 virtual machines–has things in
common with a mainframe.

  • Both contain huge pools of CPU and memory for
    virtual machines, and massive amounts of storage for objects and images.
  • Both run an OS that virtualizes workloads to
    maximize efficiency.
  • Both can deal with high volumes of transactions.
    Many of the scaling problems being encountered in the cloud were solved long
    ago by mainframe technicians.

An enterprise that runs Java on-premise may find a mainframe
useful. “z/OS is probably the most efficient place to run Java. You put the
code where the data is, and you get to remove any network latency for the

The mainframe’s place
in the modern cloud world

Can a mainframe deliver the agility, efficiency, and quality
that cloud computing provides? One beefy mainframe can be more useful than a
fleet of commodity boxes, but only for certain types of work. No one is going
to buy a new IBM z10 for small workloads–that would be like buying a big
truck for the school run–but on
a large scale it can be a better choice. Despite the high cost, mainframe use
may be cheaper than commodity hardware use for enterprise-scale workloads.

The web did not kill print, MP3s did not kill the record
industry, the mobile phone did not kill the desktop, and cloud computing has not
killed off the mainframe. These disruptive technologies have caused drastic
shifts in their markets.

Hodgson compared today’s IBM z10 mainframe with the original
System/360. “It’s a 50 year old machine, in a sense. It’s evolved and improved
and IBM’s poured billions of dollars into it, so it’s kept pace.” You could say
the mainframe of old really is dead–adapting to each new IT disruption has
changed it into a different beast.

Read more about mainframes 

Note: TechRepublic and ZDNet are CBS Interactive properties.