i5/OS V6R1 and Its Java Enhancements
February 4, 2008 Timothy Prickett Morgan
Last year, when IBM did a preview of V6R1, one of the things it talked about as a feature for the new operating system was much-improved Java performance using a new 64-bit Java Virtual Machine. This new JVM is distinct from the so-called classic 64-bit JVM, which IBM’s Rochester labs created many years ago for the platform. It is also distinct from the 32-bit JVM that IBM gave out as an alternative to customers who wanted peppier Java execution back in 2006 with i5/OS V5R4.
As I suspected when IBM previewed this new 64-bit JVM last summer with the technology preview for i5/OS V6R1, this new 64-bit JVM is one created by IBM itself and it is indeed the AIX version of IBM’s JVM that is running inside the OS/400 PASE AIX runtime environment built into i5/OS and OS/400 for several years. This OS/400 PASE runtime, you will recall, is how the latest releases of OS/400 and i5/OS run the TCP/IP networking stack and the Zend Core for i5/OS PHP engine from Zend Technologies. These are AIX implementations of the software with special tweaks to talk to i5/OS operating system features. IBM says that the new 64-bit JVM offers better performance than the classic 64-bit JVM for OS/400 and i5/OS, but the company did not say by how much.
In addition to the new 64-bit JVM running in PASE, i5/OS V6R1 sports a number of other Java performance enhancements for the JDBC protocol, DB2/400 tweaks relating to Java, and other Java features, such as support for 64 KB pages. To show off the Java performance enhancements that are distinct from the 64-bit JVM, IBM released some benchmark results based on its Trade 6.1 stock trading benchmark. The test was set up as a two-tier network on a Power5+ server with two 2.2 GHz cores dedicated to the workload. IBM’s WebSphere Application Server 6.1 was set up on the box with the 32-bit JVM delivered in 2006 (which I also suspect, but forgot to ask about, is an AIX JVM running inside the PASE runtime). With i5/OS V5R4 running, the database server driving the Trade 6.1 benchmark was able to handle just over 800 transactions per second using native JDBC database access to DB2/400. The same setup running on i5/OS V6R1 was able to handle 68 percent more transactions, nearly 1,400 transactions per second. The gap in performance on the Trade 6.1 benchmark is even larger using the JDBC inside the Java Toolbox for iSeries. The V5R4 machine handled around 700 transactions per second, but by moving to V6R1, performance increased by 78 percent to close to 1,300 transactions per second.
Some of the improvements in Java performance will, according to Craig Johnson, IBM’s i5/OS product manager in the Power Systems division of its Systems and Technology Group, be available through PTF patches to i5/OS V5R4, but exactly which ones remains unclear as we go to press.
Last summer, IBM also said that it would have a streamlined, ready-to-run Web application server integrated into V6R1, and it has made good on that promise. The so-called Integrated Web Application Server will be available for i5/OS V5R4 and V6R1 and it will be patched through the normal PTF process, not through the WebSphere iFix facility. This integrated Web server is only available on the System i and supports Java Server Faces, Java Server Pages, and Java servlets, like the regular WebSphere Application Server does, but it does not have full J2EE support, does not have a Java-based messaging engine, does not have workload management, high availability, and clustering support, and only has a single JDNI name space connection. The upshot is that this Integrated Web Application Server is set up and ready to go out of the box and has a memory footprint that is about 40 percent lower than the normal WebSphere does.
This Integrated Web Application Server has native access to DB2/400 databases and is being used by the DB2 Web Query kicker to the Query/400 tool and by the new Systems Director Navigator for i5/OS systems management tool, which is new with V6R1.