Apr 30 ’12
Technical Insights: Spring Cleaning for IMS Databases
In the spring, you may notice a recurring phenomenon in your neighborhood: One by one, your neighbors begin to perform the annual ritual of cleaning out the garage. It’s time to get rid of those old golf clubs and tackle the mounds of camping gear that have mysteriously spread to all corners of the garage. Sound familiar?
Like a cluttered garage, an IMS database also needs a deep “spring cleaning” from time to time. If you’re responsible for an IMS database, visions of disappearing database space, duplicate data, and fragmentation are probably floating through your mind at this point.
End Clutter, Stop “Data Creep”
You maintain your IMS database on an ongoing basis, obviously. But database clutter has a way of catching up with you and eating into database capacity. The result? Poor database performance, higher costs, and more risk.
By spring cleaning your database, you can avoid these problems. Look for ways to implement new processes that can help you optimize your database today and make your work easier all year.
Here are four best practices for optimizing your IMS database:
Partitioning. Using partitioning, you can virtually expand your IMS database files to accommodate more data, circumventing the 4GB per VSAM/8GB per OSAM technical limits. Proactive partitioning can reduce the expense and effort of scrubbing the data and archiving it to historical databases; for example, to meet legal requirements for records retention. IMS Version 7.1 includes a High-Availability Large Database (HALDB) capability that lets you dramatically multiply your capacity through partitioning. But it can require changes to your applications because it creates multiple data sets that aren’t completely tied together.
Today, advanced partitioning tools can extend the database multiple times while preserving its ability to act as a single database. Your applications can continue to run without any changes, reducing downtime, risk, and outages.
Extraction. Moving and archiving large amounts of data can be time-consuming, expensive, and risky. So can choosing what data to move, delete, or archive. The right approach to data extraction can save time and prevent human error.
A new generation of intelligent extraction tools can finely automate the data selection and extraction process. Using these tools, you can, for example, easily select data based on a date, extract only the data that’s newer, select data for purging or archiving, and delete the older data.
You can also protect your data better. For example, a bank could mask customer account numbers in creating a test database for an application developer building a new iPhone banking app.
Performance optimization. Optimizing performance is typically a big reason for spring cleaning your IMS database. This means looking at I/O or space—or both. Getting data out of the database file (via partitioning and extraction) is an obvious first step, but optimizing what’s left in the file can also deliver big savings and a performance boost.
Fragmentation can impede database performance, affecting your customers; for example, it can add a second or two to every ATM transaction or online account inquiry. There are tools that allow you to finely examine the fragmentation level of your IMS database, do so frequently, and automatically fix fragmentation problems—similar to those simple programs that defrag the disks on your PC. These tools can quickly and unobtrusively scan IMS indexes for fragmentation and optimize them for transaction performance with no outage required.
Wizards and workflows. Automated wizards and workflows can simplify database spring-cleaning tasks, as well as daily and weekly IMS maintenance. IMS databases keep the wheels of commerce moving and provide the back-end for many new applications, including mobile apps. There are tools that use GUIs to simplify and automate IMS database maintenance tasks so no IMS knowledge or skills are required. For example, wizards, knowledge bases and intelligent workflows can walk a DBA through a job task and even build the JCL for him.
By making an annual appointment with yourself for IMS spring cleaning, you can ensure you’re taking full advantage of these advancements.