IMS is Alive and Kicking
Although I usually cover DB2 in this column, we will
take a short break this issue. The purpose of this
column is to examine data management issues on IBM’s
zSeries platform and DB2 is not the only game in town.
So this month let’s check on the status of IBM’s other
mainframe DBMS product, IMS.
IBM celebrated the 35th
anniversary of IMS last year – which, in this industry, is a very long time for
a software product to thrive. Even more amazing is that IMS continues to grow.
In just the past 2 years IMS has experienced a 55% growth in terms of MIPS, as
well as a new version (V8) with a lot of new functionality and the announcement
of yet another new version (V9) on the horizon. You can connect to IMS databases
from just about anywhere these days due to the robust connectivity offered by
IMS Connect and the Open Transaction Management Access (OTMA) facility.
While hierarchical database systems have been surpassed in the marketplace by
relational and SQL products like DB2, IMS can brag about its long and proud
legacy that continues on today. According to IBM more corporate data is managed
by IMS than any other database system. IMS manages over 15 million gigabytes of
production data. And more than 95% of the companies in the Fortune 1000 use IMS.
terms of transactions managed, IMS is even more impressive. IBM claims that over
50 billion transactions are run through IMS daily. And close to 200 million
users a day are served by IMS. Why does IMS continue to enjoy such success when
relational products are more mainstream and easier to use?
One reason is speed. One high-end IMS customer handles 120 million transactions
a day; 7 million in a single hour! With IMS data queued sharing on a single
processor with database updates IMS handles 21,000 transaction per second and
almost 1 billion transactions a day at another site. Another benchmark shows IMS
serving 6000 transactions per second across TCP/IP to a single IMS. These are
impressive numbers indeed.
Modern application development approaches can be used with IMS, too. The IMS
Open Database Access facility (ODBA) provides a callable interface for easier
database access. And as of V7 IMS adds Java support and tools to simplify Java
development with IMS. Today, IMS developers can:
Write Java applets or applications that access
IMS transactions with template assistance from the IMS Client for Java;
Use the IMS Web Studio tool to build end-to-end
solutions for accessing IMS transactions from the Internet;
Use the Java-based IMS Object Connector Class
Definition Tool to generate data objects for use by IMS Object application
Use the class libraries and Java beans of the
IMS Connector for Java to develop Java applications that access IMS.
And IMS Java Remote Database
Services coming in V9 provides IMS Java application programs distributed access
to IMS databases. That means your non-z/OS programs will be able to access IMS
data over the Internet using a secure protocol with local or global transaction
semantics and a standard API.
And if you haven’t created an
IMS database in awhile, you might be in for some surprises. HALDB, a new format
introduced with IMS V7, allows database partitioning – and you can grow up to
10,010 data sets per database resulting in a database size of over 40 terabytes.
HALDB databases also help address some of the pesky management and
administration problems that have plagued IMS for years. With self-healing
pointers, reorganizing a partition does not require changes to secondary indexes
or logically related databases. HALDB also does away with Prefix Resolution,
Prefix Update, and secondary index rebuilds. Of course, HALDB requires a
different format so you would have to convert existing IMS databases to take
advantage of these features.
IMS also participates in the
e-business world of 24/7 applications. Using a combination of IMS and third
party tools large organizations of every type are enabling their employees and
customers to access business critical IMS data round-the-clock over the Web. The
next time you make a flight reservation, access your frequent flyer miles, view
your investment portfolio, or track a shipment over the Web just stop and think
– “I probably have IMS to thank for this service.”
Finally, IMS databases are
getting easier to manage. IBM’s autonomic computing initiative delivers
self-configuring, self-healing, self-optimizing, and self-protecting features to
IMS V8. Combine these features with third-party tools that improve availability
and simplify reorganization, compress IMS data to reduce storage needs, automate
and coordinate changes of system definition elements while transactions remain
online, and speed up and simplify backup and recovery of IMS databases and you
have a very robust environment for leveraging your enterprise data.
Truly, there is no need to
worry about having to convert your IMS databases to DB2 (or worse yet, another
DBMS on another platform). IBM continues to enhance IMS with the features it
needs to continue to support your business. Yes, IMS may be old, but it has
evolved over the years to support the needs of modern databases and
applications. And just because something is old, doesn’t make it obsolete. I can
vouch for that personally!