Developer > Java

Supercharging SAP Applications Running on IBM i

With IBM i 6.1, IBM released a version of IBM Technology for Java* (IT4J) optimized for SAP NetWeaver. This state-of-the-art Java technology provides immediate benefits over the existing technology when running SAP NetWeaver Java applications. These benefits include:

• Improved processor utilization (less processing required for same work)
• Improved memory utilization (reduction in memory footprint)
• Increased Java performance and capacity

IBM Technology for Java

With the release of IBM i 5.4, IBM rolled out IT4J, which set in motion the transition away from the existing Classic Java technology. Classic Java technology has been around since i5/OS* V4R3 and served the Java needs of IBM i customers well. But, like all technology, there comes a point where enhancing the original no longer provides the additional value customers require. It’s then necessary to apply the knowledge obtained and lessons learned to building new technology from the ground up. Such is the case with IT4J. Though the Classic Java technology has been very reliable and scalable, IT4J provides many benefits and improvements, such as improved garbage-collection algorithms, more efficient memory management, advanced Just In Time (JIT) compiler optimizations, a wide array of industry-standard tooling and more.

With IT4J, the different IBM server platforms have converged on one common Java technology. This has led to development synergies and efficiencies, resulting in performance gains and memory-use reduction. The IT4J technology is the result of collaboration among multiple IBM software-development labs and IBM research. The IT4J stack includes a JVM*, JIT compiler and optimizer, class libraries, utilities, and industry-standard tooling—all new and all state-of-the-art.

With i 5.4, a 32-bit IT4J stack shipped along with the 64-bit Classic stack that was included in its predecessors since V4R3. The new release offered the choice of Classic or IT4J for running Java applications. However, since it was only available as a 32-bit version, some large Java applications—including SAP—were unable to take advantage of the new technology. With IBM i 6.1, a new 64-bit version of IT4J ships along with the 32-bit version. The Classic stack is included as well, but this will be the last release with the Classic technology. Future versions of IBM i will include only IT4J in 32- and 64-bit.

Java and SAP

SAP first started leveraging Java as part of its solution offerings with the purchase of a Java application server, named InQMy. Since that acquisition, SAP has worked on integrating this Java application server into the core SAP application framework. After much development, the SAP NetWeaver Java application server is now an integral part of the SAP NetWeaver product family. Many core SAP applications leverage the Java application server, including Enterprise Portals, Process Integration and Business Intelligence.

SAP has supported IBM i Java technology since it first released Java applications. IBM i and SAP development teams have worked closely to ensure that the Classic Java technology stack was optimized for SAP workloads. Now the collaboration has extended to the new 64-bit IT4J, giving you more options.

Making the Move to IT4J

The joint SAP and IBM development teams first started looking at IT4J technology for use with SAP applications almost a year before the release of i 6.1. The SAP NetWeaver releases currently in the field, SAP NetWeaver 2004 and SAP NetWeaver 7.0, both require the 1.4.2 Java runtime environment* (JRE*) and a 64-bit JVM. Initially, the 1.4.2 JRE wasn’t available with the IT4J product offering. Development teams performed analysis that confirmed the feasibility and value of making IT4J 1.4.2 available and using it for SAP workloads. Benefiting from a close partnership between SAP and IBM development, the integration and testing of IT4J 1.4.2 began with strong synergy between the two development organizations. Since IT4J 1.4.2 was being provided specifically for SAP applications, IBM i development was able to work closely with SAP development to optimize the IT4J stack specifically for SAP Java applications, providing even more value to SAP on IBM i customers.

In addition to the work of bringing IT4J 1.4.2 to the IBM i, the SAP development team invested in providing easy-to-use tooling that would help in switching from the Classic stack to the IT4J stack. This new SAP Java configuration tool enables a system administrator to automatically change the SAP Java application server configuration to use the IT4J stack. The tool automates many of the manual configuration steps required, decreasing the chance for errors and problems.

To simplify switching JVMs, SAP provides a tool, available only on IBM i, that automates the switch process.

Next page: >>