Despite predictions to the contrary, the mainframe is
still motoring on. Danny Bradbury examines where using the
big machines pays off, and where applications are best migrated to
clusters of smaller systems
Predictions in the IT business are two a penny, but good
predictions are rarer than hen's teeth. For example, in 1991 a
marketing manager at Informix predicted that the mainframe would be
dead in 2000. In 2004, revenues for IBM's zServer mainframe
business grew by 15%. Not bad for a dead product category.
Then in 2005, IBM (which incidentally bought Informix's ailing
business in 2001) launched the 38-processor Z9, its biggest
mainframe yet. So much for predictions.
Still, the mainframe market has its fair share of challenges.
One of the problems with mainframes and the applications that run
on them is that they are often relatively old. So are the people
that make them work, says Patrick Pochard, who runs Computer
Associates' mainframe centre of excellence in the Czech
Republic.
"Most of the mainframe experts today are in their 50s. The
percentage of people younger than that is very small," he says.
"This is not good because even if you provide great hardware,
systems and products, if you do not have the right people to
maintain it and keep it up and running, you are in trouble."
Skills are not the only problem facing mainframe users.
Suppliers contend that mission-critical applications should stay on
machines with high reliability and strong performance, but this is
changing. Mainframe and minicomputer applications are increasingly
devolving to high-end multiprocessor Unix boxes or clusters of
Windows machines.
For example, Swiss air traffic control firm Skyguide recently
migrated its radar data processing software from a Data General
MV9800 minicomputer to a Windows server. It does not get much more
mission critical than that.
The MV9800 was already considered obsolete when the company
installed it in 1995, according to Philippe Chauffoureaux,
Skyguide's radar data processing group leader. "The air traffic
control world back then was quite conservative," he says.
The turning point for Skyguide was when the support for the
MV9800 from EMC (which owns Data General) was due to expire.
This created big problems for Skyguide, as rewriting the
software would have taken too long and commercial off-the-shelf
software was going to be too expensive. So Chauffoureaux's team
decided to migrate the code instead.
"PCs benefit from the mass market effect," Chauffoureaux says.
"Companies like Asus or Intel sell millions of pieces of hardware
so they are tested well. But if you take specialised hardware, it
is often being used by only 100 to 1,000 customers."
Mainframe suppliers are working hard to protect their market.
For example, most of them these days run open operating systems
such as Linux, and can do so in multiple virtual partitions.
Chander Khanna, vice-president and general manager of the
ClearPath solutions and services business at Unisys, says the
company's mainframes now run Java applications alongside Windows
and Linux, which can run on separate processors in the mainframe
chassis.
But such provisions are not enough for some of Unisys'
customers. For example, Express Newspapers recently abandoned its
Unisys mainframe for Intel-based Windows servers.
Simon Cohen, Express Newspapers' product development manager,
says his team had already pulled many applications off the
mainframe onto other equipment. They finally ended the lease on the
mainframe after migrating an eight-year-old Cobol-based prepress
processing application onto an open platform.
"The saving that we have made is on the support and service from
Unisys. That paid for the migration and we saved money to boot,"
says Cohen. The migration, including all of the Windows hardware,
cost £300,000.
"It gets to a point where there is so little running on the
thing that you cannot justify it to the board," he says. The
remaining savings went on new equipment, including Apple Macs.
Development opportunities have soared since moving away from the
mainframe platform, says Cohen. "Running [the system] on Windows
has given it a new lease of life, mainly because of the database
that is behind it," he says.
The firm originally used a flat file database but moved to SQL
Server's relational structure. The initial plan was to run the
migrated system for four years at the most and then redevelop, but
now things may change. "It has become a lot easier to modify it and
write new parts," Cohen says.
This type of migration, according to Mike Gilbert, director of
product strategy at Cohen's chosen migration software tools
supplier Micro Focus, is called "lift and shift". The lift and
shift process takes existing legacy code and ports it to an open
platform like Windows for recompilation.
Generally the code has been written using a version of a
language such as Cobol or PL/1, with additional proprietary
features added by the mainframe supplier, which is a problem that
the migration tool can help with.
Even so, migration is not always plain sailing. At Skyguide,
Chauffoureaux used the services of migration consultancy Transoft,
a Micro Focus partner. Transoft took the legacy code and delivered
new code to be tested and recompiled by Skyguide's internal
team.
The Ada and Fortran migration went according to plan, but the
assembly language (second generation mnemonic code designed to
speak more directly to the hardware) was more problematic.
"They rewrote 90% of what was delivered because the quality of
the port was not at the level we would expect in a multi-level
environment," says Chauffoureaux.
The problem lay with the multithreaded, multiprocessor nature of
the original hardware configuration, which could have been more
expertly written in the first place. With a single-processor box it
would have been much easier, says Chauffoureaux.
The team spent around six months rewriting the assembler code.
Such unforeseen problems can turn a product from "lift and shift"
into "lift and sift".
Nevertheless, the benefits for Skyguide of moving away from a
minicomputer environment were impressive. For one thing, says
Chauffoureaux, it was impossible to use separate systems for
development and testing purposes, prior to the migration. These
days the company is running multiple copies of the same system for
training, simulation and testing purposes.
"That is something we could not do in the past because we could
not buy new MV9800s," he says.
But what options exist for companies that want to modernise
their mainframe applications without moving away from their chosen
platform? One approach is to take the existing application and wrap
it with code that lets you create new interfaces for end-users.
Doing it this way can also allow you to logically view mainframe
applications as service-oriented architectures or object-oriented
systems. However, be prepared for the cost of the middleware and
the middle-tier software development to escalate.
One company taking this approach is Allianz Cornhill Insurance.
Mainframe operations manager Keith Walker still uses a Z900, a
mainframe a couple of generations behind IBM's Z9 machine.
"A significant proportion of the company's business is operated
from the mainframe," he says. "The reason for that is reliability,
scalability and to some extent cost effectiveness of the platform
when looked at in an efficiency context."
People often forget to factor ongoing support into costs when
migrating to mid-range and PC-based systems, says Walker.
Walker manages the mainframe, which runs line-of-business
applications for the insurance market, using Computer Associates'
tools for tasks like job scheduling. It has experienced 100% uptime
in the past 12 months, and has only been down twice in the past
four years.
"You do not have to move these applications to provide a 21st
century front end," says Walker.
Allianz Cornhill Insurance is implementing web-based front ends
for its mainframe applications, which will replace the traditional
green screen interface. It is using IBM's Websphere MQ middleware
to transform the applications. Pricey? "Yes, but it is horses for
courses," says Walker.
One of the most important developments for Walker has been the
change in software licensing models on the mainframe. To bring them
more in line with utility computing movement in the open systems
market, mainframe software suppliers have been reconfiguring
licence arrangements to charge customers for how much computing
power they use.
"Some suppliers are going towards the 'pay for what you use'
model and Computer Associates is one of them," says Walker, adding
that he may only be using 50% of the mainframe's capacity at any
one time.
"The new pricing model uses a tool to measure how you use each
piece of software and there is a scale of charges based on
that."
This makes the mainframe proposition more effective for Walker,
because including depreciated capital expenditure on the mainframe,
the hardware cost amounts to just 20% of the total running cost of
the system.
Mainframe hardware and software suppliers may be trying to shake
up their business models to help fight a rearguard action against
increasingly powerful mid-range boxes, but they have their work cut
out.
IBM's revenues on the zSeries may be up over last year, but it
is likely that while the percentage of its customer base running
very high-end high-mips applications will grow, the sub-1,000 mips
market will continue eroding from the bottom up.
For an increasing number of smaller customers, the best things
really do come in small packages.
Case study: IMS cleans up with a mainframe and clustered
PC combination
For some, neither a mainframe nor a PC server can completely
satisfy their computing needs. For Terry Kelly, director of
production support for IMS, a combination of mainframe and
clustered PCs and Unix boxes offers the best performance.
IMS collects and cleans medical data from 29,000 suppliers at
225,000 global sites. The data, which arrives in thousands of
unique formats, must be correlated and formatted for each
customer's system.
The IMS system uses a mainframe for much of its transaction
processing (it handles one billion transactions each month), but it
also runs farms of Windows and Unix servers. When necessary, it
pulls some jobs off the mainframe onto these farms for initial
processing before pushing them back to the mainframe.
This is because sometimes the cost of processing a batch of data
on a non-mainframe cluster can be lower than doing it on the bigger
box.
"Where data volumes are small enough for an NT or Unix solution
to handle that first stage of processing, we can take it on there,"
says Kelly.
Similarly, if the jobs require manual processing, it is easier
to create a workstation graphical user interface to the mid-range
operating systems than to the mainframe, he says.
Job scheduling is an important part of making the platforms work
together. A job often needs to be processed on both the mainframe
and a Windows or Unix cluster at different points, and in different
locations, so Kelly needs to automate it as much as possible.
He uses ESP, a job scheduling system from Cybermation, that
automates the transfer of batch data between these resources.
The company is unlikely to abandon its mainframe in the
immediate future. As the main transaction processing workhorse and
the repository for a huge 79Tbyte datastore, it sits at the centre
of the IT infrastructure.
But IMS' use of open systems to complement its mainframe shows
that sometimes the two worlds can co-exist.