z/Bottom Line: Hardly Over the Hill

by Eric L. Vaughan
April 1, 2005

It’s all a matter of perspective. While many anticipate (dread?) the quad-decade milestone that causes others to “celebrate” your pending demise, it really depends on your point of view. 

So, spare the black balloons. No yard signs needed here. Tombstones would be as welcome as a news reporter in Barry Bond’s living room. 

Accompanying this issue of z/Journal is a special supplement commemorating the 40th birthday of the VSE operating system. To everyone who participates in the mainframe industry—even if you’re of the z/OS-OS/390 persuasion—you should pause in admiration for this incredible moment. It’s not often that victory is achieved against seemingly insurmountable odds, as the tale of VSE’s illustrious history reveals.

There were three major debuts in 1964 that endure in quality and performance today: the Ford Mustang, the Beatles, and the Disk Operating System/360 (DOS/360). IBM introduced DOS shortly after the birth of the revolutionary announcement of the S/360 line of computers. 

The S/360 derived its name from the 360 degrees on the compass, meeting all needs in all locations—quite clever indeed. Apparently, all the marketing energy had been used up by the time they decided to name the operating system for the newly announced hardware, the stunningly creative “OS,” or Operating System. But beyond the uninspired name, OS had one other problem:  It simply wouldn’t fit in the memory of the smallest 360 computers. So, the creative engineers in Endicott crafted a subset of functions from OS that would fit. And DOS was born.

Over the next four decades, as the 360 hardware evolved to the System 370, 43xx, 308x, 3090, 9370, Multiprise and now the zSeries brand of processors, the operating systems have kept pace with innovation—although one by design and the other by default. OS became OS/MFT, OS/MVT, MVS, MVS/XA, MVS/ESA and the latest announcement concurrent with the zSeries hardware announcement—z/OS (back to that inspired OS again!). 

DOS also created offspring; although nearly all follow-on releases were ostracized as bastard children. DOS begat DOS/VS, DOS/VSE, VSE/AF, VSE/SP, VSE/ESA and now, z/VSE. At nearly every step of its maturation, DOS faced some force within IBM that was determined to “sunset” its life on the computing planet. There were overt efforts, such as the VSE-to-MVS conversion task force chartered by the now-extinct GUIDE organization. And there was the famous speech in 1989 when Dr. Ed Altman stood in front of the VSE faithful and nearly shouted, “You will never see VSE/XA.”  Turns out he was right about that. VSE skipped XA for the more robust ESA enhancements.  

What happened over those 40 years while IBM was planning to unify its mainframe operating systems? Thousands of users around the world happened. Shops that found they could do more but spend less continued to insist they would ignore IBM’s apparent attitude of, “You will go to MVS or you will go to hell!” Most VSE users asked, “What’s the difference?”