Mainframe Programming to Make a Comeback?

ajw1976 writes to tell us that IBM has released a series of announcements today "introducing many new software tools, academic programs, and support for outside developers." The new releases are designed to help entice programmers and businesses back to the mainframe. From the article: "The announcements, according to analysts briefed on them in advance, signal a shift from defense to offense in the company's mainframe strategy. Last month, I.B.M. introduced a machine priced at $100,000, about half the previous starting price for its mainframes, which can run up to several million dollars. The announcement of the low-end mainframe was made in China, which I.B.M. regards as a promising market for the machines."

Comments

mainframes rock

[yagu]

Cool, I can dust off my old bell bottom pants and platform shoes. I knew they would come back!

All seriousness aside, I started out coding for mainframes, mostly assembly. To this day some of the most screaming and cool programs I ever wrote were on mainframes (wrote (in assembly) an on-line trouble logging system to replace a paper system back in '76).

I did lots of COBOL programming and maintenance for a major, now absorbed by increasingly corrupt larger pseudo-telcos, telco. COBOL, not the most exciting language, but the throughput and data integrity of those days I've not seen matched since (and I still love Unix as my first choice for environment).

Which brings me (and us) to what I think works in favor of mainframes having a chance at a major comeback:

• TCP/IP stack not builtin and assumed. In the old days, if you wanted to communicate with other architectures it was a RPITA. With internet protocol everything is easy. Now you can take the raw power and integrity of the mainframe and lace it up to foreign technology.
• IBM's OSS/Linux participation. I don't know if IBM has completely jumped on this bandwagon, but they've made contributions, and you can "do" Unix on their mainframes. And, they have cool passthrough mechanisms, how cool is it to write a shell script that can access VSAM data? If you don't know, it is very cool.
• Mainframes historically have gi-huge support organizations built up around them. They have backups to backups. And, it's all managed for you.
• Mainframes are single point of support, you all know you're using the same configuration (well, to the extent you're in the same virtual system on a mainframe).
• Mainframes aren't Windows (sorry, had to put that in for the troll mods.)

This is a partial list. I've long lusted for the raw power of mainframes with the standard support and the nimble Unix utilities.

Re:mainframes rock

[AuMatar]

Mainframes are just too different a world. Its not just performance (in fact, the performance difference is due only to an insane number of cores and memory, not an inherently better chip), its reliability. Some IBM mainframes have CPUs that do every instruction twice in parallel (different cores on the chip). If the results don't match, it turns the chip off as defective and shunts the program to a backup. That kind of thing just doesn't exist in traditional architectures.

Although in the days of clusters, I don't know if mainframes can make it. Clusters have the same edge and much lower cost. I think we're more likely to see some of the OS advantages of mainframes get ported down.

Re:mainframes rock

[morgan_greywolf]

Does anyone know of any (non VENDOR) studies & comparisons vs traditional computer architectures?

Mainframes are traditional computer architecture! Unix is 'new' compared to mainframe technology.

The modern mainframe is, in general, vastly more reliable than even the best of the best of 'big servers.' Mainframes are generally redundant to the point that you can change out thefr CPUs, memory, drives, etc. without turning the power off or rebooting the machine. Linux and Unix servers might boast about a couple of years of uptime, but many mainframe systems have been up for decades.

Many mainframe systems can process orders of magnitude more transactions than your typical *nix system running Oracle -- even when compared to systems with SMP, gigabytes of memory and the latest in high-speed storage. In fact, the stuff that people use nowadays for high-speed, high-reliability storage -- storage area networks (SANs) -- have their roots in mainframe technology. EMC, one of the market leaders in SANs was formerly part of Data General. In fact, so does most of the rest of your high availability 'enterprise-class' technologies -- SMP, NUMA, clustering, etc. Where do you think Linux's current SMP technologies came from? IBM. Who developed them on mainframes, ported them to AIX and then eventually ported them to Linux.

Massively-clustered systems like Google's are quickly become the norm for high-end stuff. But there are certain things that will probably always run on Big Iron. Whenever tasks are mission-critical and need to 24x7 and 'three 9's' doesn't even touch the tip of the iceberg in what you need in reliability -- you'll see mainframes running those tasks more often than not.

The value of the mainframe is in the hardware...

[kcbrown]

Mainframes don't have the fastest CPUs around. Instead, they have the most reliable ones.

The same is true of their memory subsystems, their disk subsystems, etc., though their backplane performance tends to be second to none. Mainframes are designed for throughput.

Mainframes are capable of staying operational for decades at a time. If you don't want your computer to ever go down and can afford the price, a mainframe is what you want.

One other nice benefit: they've had virtualization figured out on mainframes since the 1960s, so allocating resources is a relatively easy thing to do.

If you're interested in finding out what the older mainframe OSes were like, check out the Hercules IBM mainframe emulator here.

Forget z/OS, try Linux under z/VM

[swamp boy]

For any organization that may contemplate getting into mainframes -- skip z/OS (MVS). MVS is what most folks dread when they think about mainframes (JCL, pre-allocate datasets, etc.). A modern mainframe (z/990 or z9) running z/VM (5.1 or 5.2) and a bunch of linux guests is *COOL STUFF*. What's really cool is when you need to setup a temporary testing environment -- no problem, just add a half-dozen configuration statements to your "USER DIRECT" and clone an existing guest image to the new machine's disk volumes. Done! Need more memory in that virtual Linux server? No problem, bring up USER DIRECT in XEDIT and edit a single line of text and issue DIRECTXA. Restart the linux guest and now is has more memory. Disk space (volumes) can be added while the Linux systems are running (add as many as you need).