Looking Back

While in Atlanta for Networld+Interop I had dinner with a group of fellow journalists and former colleagues that now carry the banner of Linux and Open Source. Over dinner we debated the future of the Open Source movement, and how it has (will) change the world. As the ‘poster child’ of the Open Source revolution, Linux was brought up as a shining star of modernity, casting aside the AS/400 as a tired old platform that had reached the end of its useful life.

The question, “Why would anyone buy an AS/400 when they could use a cutting edge OS like Linux?” was posed. My protestations went unheard as my fellow journalists went on an Open Source induced ‘trip’, complete with the peace and love message reminiscent of 60’s era anti-war rallies. Open Source will save the world. Linux will help you expand your mind. Linux is the hippie and AS/400 is the establishment. Don’t trust any OS over 30!

Well, if that’s the way they want to play it, I’m game. Here’s my view of history, revisionist or otherwise, that might make you think it’s Linux you shouldn’t trust, not AS/400.

1969 Ken Thompson of AT&T Bell Labs writes the first version of what will eventually become the UNIX operating system.

1974 The ‘Open Source’ movement is born! UNIX source code is distributed freely to universities.

1978 IBM introduces the System/38, follow on to the System/3 family of minicomputers. Proposed by Dr. Frank Soltis in 1970, it incorporates the new concepts of the high-level machine interface and the single-level store.

1979 The ‘Open Source’ movement takes a blow! AT&T announces its intention to commercialize the UNIX operating system. In light of this development, the University of California at Berkeley creates BSD UNIX. Many vendors adopt this as the base of their own proprietary operating systems, notably Sun Microsystems and Digital Equipment Corporation.

1980 First System/38 rolls off assembly line in IBM plant in Rochester, Minn.

1983 AT&T releases UNIX System V. BSD 4.2.

1985 Silverlake project to produce computer that could run System/38 and System/36 applications is proposed.

1987 System V Release 3 is made available. HP and IBM adopt System V as the base for HP-UX and AIX respectively. AT&T and Sun agree to merge System V and BSD.

1988 The AS/400 is born! First units are shipped to customers in August. MIDRANGE Systems debuts in September.

1990 AT&T releases System V Release 4 (SVR4). HP, IBM, and DEC to combat Sun and AT&T form the Open Software Foundation.

1991 OSF-1 is released. Only DEC adopts it. FreeBSD and Linux, openly distributed versions of ‘UNIX’ first released.

1992 Sun releases Solaris, its SVR4-based operating system. 64-bit OpenVMS operating system is released for the DEC Alpha processor.1995 IBM moves AS/400 from proprietary CISC processor to 64-bit RISC processor. Immediately, all AS/400 applications take advantage of the new 64-bit processor due to the Technology Independent Machine Interface.

1997 IBM enhances AS/400 and renames it AS/400e.

2000 IBM is first to use Copper/Silicon-on-Insulator (SOI) processor technology. AS/400’s that use this technology become eserver iSeries 400. 64-bit Linux is available on Compaq Alpha processor, but 64-bit Linux on Intel processors waits for Itanium release.

So there you go. If you look at the history books, you’ll find that the AS/400 isn’t all that old after all. In fact, Linux has its roots in an operating system that was released in 1969! Linux fans should refrain from writing me to tell me that Linux is not UNIX. It is, and you’re not fooling anyone.

So we have established that the AS/400 is not an “old” platform. Well, at least we have established that it is not as old as any UNIX or UNIX-derivative operating system. What does this mean, though?

IBM has announced that the leading-edge AS/400e models are becoming part of the eserver iSeries 400 line of systems. It did this because there is a perception that the AS/400 is old technology. I can understand this since everyone knows “perception is reality.” But is it?

Maybe, maybe not. Let’s examine today’s iSeries 400 and compare it to other computing platforms.


The iSeries 400 uses the IBM Copper/SOI microprocessors. These state of the art chips are driving unprecedented performance levels in the AS/400 line as evidenced by recent top-notch benchmark performances. See “Benchmark Testing Shows Power of 8xx Series” in the July 24, 2000 issue. IBM has set a clear path for the iSeries to use the most advanced processors as they come available.

As for the iSeries’ competitors, none use processors with fabrication technology as advanced as the Copper/SOI chips. It can be argued that for raw performance, the Compaq Alpha systems compete on a level field with the iSeries, but systems from Sun can’t match the single processor performance of the top end iSeries systems. What Sun lacks in single CPU performance, they attempt to make up for in SMP performance. Again, they fall short with 24-way iSeries 400 Model 840’s outperforming 64-way Sun Enterprise servers.


From the first day it was introduced, the AS/400 had a unique architecture that was optimized for business computing. Designed from the ground up to protect a company’s IT investment, the AS/400 has been able to evolve, from a hardware perspective, without breaking application programs. The switch from CISC to RISC in 1995 went off without a hitch. There was a slight performance penalty the first time an application was run after bringing it up on the new RISC boxes, but after that, the applications took full advantage of the 64-bit processors, without even a recompile.

UNIX systems vendors, on the other hand, have repeatedly forced IT managers to switch platforms mid-stream, requiring a lot of application reprogramming and a major amount of trouble. For example, when Sun made the transition from Solaris 1 (SunOS, a BSD derivative) to Solaris 2 (an SVR4 derivative), customers were forced to do a major overhaul of their application programs, including, but not limited to, recompiles and rewrites.

Application Development

In any conversation about the AS/400, RPG will certainly be used as an example of how out of touch the AS/400 is. I won’t use this as an opportunity to jump on my soap box and pontificate about RPG, one way or the other, but I will say this: For creating business applications, RPG is a great language. It is not the language I would use to write an operating system or compiler, but it does lend elegance to writing commercial business applications, like AR, AP, Payroll, Inventory, etc.

In any case, the state of application development has advanced in the 35 years since RPG hit the street and the AS/400 has kept pace with these trends. The AS/400 can run C language programs and it is a good platform for creating server-side Java applications. Using the many tools available and WebSphere, you can definitely use the AS/400 to create state of the art e-business applications. In fact, I spoke to one company that said they would rather deploy their pure Java application on an AS/400 then any other platform due to its stability, reliability, and scalability.

Certainly you can develop Java on Windows 2000, Linux, or any other UNIX clone, but will it run any better there? Doubtful.The key to application development on the AS/400 is to understand that it is not a great platform for application development; it is a great platform for application deployment. Develop on Linux or Windows or whatever, but deploy to the AS/400 and take advantage of its performance, scalability, and reliability.

So what’s to stop you from using the AS/400? Nothing. If you are currently an AS/400 user, there is no reason to stop being an AS/400 user. If you aren’t, then maybe you should take a look at it. With PASE, LPAR, and soon the ability to run Linux in a partition, the AS/400 might just be the best new old computing platform around today!

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