I still get a chuckle over the way people react whenever I mention the words "AS/400" and "enterprise class" in the same sentence. Yes, I admit to being biased toward the platform, having spent many years using it. But I still find it amazing that some people continue to think of the AS/400 as a mere green screen, report-based system. It's actually a very reliable, open, scalable, and easy-to-use server that's suitable for all kinds of enterprise applications, whether they be batch or interactive workloads, enterprise resource planning (ERP) systems, or business intelligence suites.
And it keeps getting better. With Version 4, Release 5 (V4R5), the latest incarnation of the server's OS/400 operating system, IBM has added such features as native support for Java, a stellar DB2 implementation, support for Unix applications, and unparalleled security. True, V4R5 may be aimed more at enabling IBM's new hardware than at offering new software functionality, but there's still enough here to put to rest any questions about the AS/400's enterprise applicability.
Slicing and dicing
As a company grows, it adds more software and disperses itself over a wider range of geographical locations, meaning it must also divide its workloads. Partitioning - splitting one server's hard disk into multiple segments, each with its own processor, memory, and disk - is one way of doing that. This has been a common practice in the mainframe market since the mid-1980s, but AS/400 users couldn't create partitions until the previous release (V4R4) of OS/400. Based on the IBM S/390 operating system, which permits flexible and granular allocation of system resources, V4R4 also lets you allocate interactive performance and provides high-speed internal links between each partition.
V4R5 continues that tradition. But the big news is that, with this release, OS/400 can now support a staggering 24 active partitions (as opposed to the previous high of 12). The catch is that you must also use one of IBM's new high-end 8xx servers to exploit this feature.
The new release also boasts much-improved system management capabilities. In days of old, if you shut down a primary partition with secondary partitions still active, you forced an abnormal termination that would lead to longer initial program loads. But if you shut down a primary partition with V4R5, OS/400 will automatically shut down the subsequent secondary partitions in a normal manner. Furthermore, users who upgrade to an 8xx server will find that IBM has also simplified the installation process for partitions, offering new support for external stand-alone CD-ROMs drives.
For those who haven't heard yet, the AS/400 can also support Unix quite nicely. Introduced earlier this year, Portable Application Solutions Environment (PASE) for the AS/400 offers a subset of AIX interfaces, providing a run time for Unix application binaries to execute directly on the same PowerPC processor as the AS/400.
In addition to being a fully integrated component of OS/400 (with a subset of the AIX 4.3.3 run time), V4R5 also provides a full locale set, including new Euro support, a fully functional X Window System client run time, and the Motif run time. While not intended to be an operating system on its own, this feature does offer an integrated OS/400 run time for porting Unix applications that have otherwise been excluded. Moreover, once applications have been ported, you can run them natively on the AS/400, thereby taking take full advantage of the server's stellar file systems, security, and DB2 Universal Database.
Java done justice
Unless your business has been operating in the Bizarro World, by now you've at least thought about deploying applications on Java. Once again, V4R5 can help.
In terms of sheer speed, the AS/400 recently beat the pants off Sun in the VolanoMark Java performance tests. Some of these performance boosts are due to V4R5's ability to implement a direct execution stage (which generates fully compliant, optimised Java applications) and perform interclass binding between the classes within a Java archive (JAR) file. The class files are preprocessed using a transformer, which creates an associated, persistent, and optimised program object.
For default executions, the program object contains a compiled, 64-bit RISC machine instruction version of the class. Moreover, the Java interpreter does not interpret the optimised program object at run time, but rather when the class file is loaded.
IBM has also beefed up its AS/400 Toolbox for Java. Thanks to new service programs, native AS/400 Java programs, native FTP support, and even user authentication via servlets, it is now easier to access and use AS/400 resources. The Toolbox also lets you retrieve result sets via Java Database Connectivity, list users, gain access to spooled files, look at printers, and even display lists of records retrieved via record-level access. Meanwhile, a new set of HTML classes and an update to the OS/400's old graphical classes equals an easier-to-use, more functional set of tools than XML-based Java class libraries and software.
Similarly, IBM has separated interface classes from implementation classes, allowing for true three-tier application support. Now you have a choice between running the two different classes on either the same Java Virtual Machine for a standard two-tier application, or on different machines for three-tier applications. You can even run multiple Java Development Kits - including 1.1.6, 1.1.7, 1.1.8, and 1.2.2 - all on the same Java Virtual Machine, or connect and work from OS/400 releases as early as V4R2.
Because the Toolbox can now support both Java 2 and Linux, you can integrate with and operate from a multitude of platforms. Furthermore, added support for Swing 1.1 means you can use the enhanced functionality and performance available in the latest release of the Java Foundation Classes.
Deriving value from data
Changes have also been made to the Operations Navigator, IBM's graphical front end. One particularly nifty feature, Visual Explain, provides a pictorial representation of how a query runs, thereby helping database administrators optimise performance.
Elsewhere, IBM has doubled the maximum number of tables that can be referenced in a SQL statement, leaping from 128 to 256. The number of rows in a table has also jumped to 4 billion, and support for journal receivers has risen to one terabyte. Other new features include the ability to encrypt passwords across a Distributed Relational Database Architecture (DRDA) session. With DRDA, you get a standardised database protocol that provides fast, reliable, and secure access to your data within a client-server environment.
The final cut
More than 700,000 AS/400 users can't be wrong. IBM's server has always delivered unparalleled uptime, low cost of ownership, remarkable ease of use, and a range of excellent third-party software solutions. Yes, moving to a new enterprise server can be expensive and difficult, but when you consider what the latest OS/400 release has to offer, it's a decision well worth considering.
The Bottom Line
OS/400 Version 4, Release 5
Business Case: The latest release of OS/400 builds upon IBM's legacy of providing mature, reliable platforms for mission-critical enterprise applications. V4R5's range of easy-to-use features makes it a must-have for current AS/400 users.
Technology Case: V4R5 boasts substantial Java performance improvements over previous releases. By adding the DB2 OLAP (online analytical processing) server onto an already impressive query, reporting, and database engine, true business intelligence on the AS/400 is a reality.
- Can be divided into 24 logical partitions
- Extremely stable
- Improved Java performance
- Native support for Unix applications
- Enhanced database support
- Investment in 8xx server required for some features
Platforms: Any AS/400 RISC model.