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Was There Ever a Maniframe PC?

lyonadmiral said:
In exactly the same boat, I have so much knowledge of legacy systems that there is very little room in my brain for the new stuff. Very painful. :(
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The most important thing, that I am still slowly learning, is how to decide 'what to forget' and then to actually forget it. Some things are worth remembering; some things, not so much.
 
Chuck(G) said:
I'm speaking of the classification of the time these machines were current. ...
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Oh, absolutely.

I suppose one way to define a mainframe without bringing in physical size would be the types and sizes of its peripherals. Minis always seemed to be peripheral-poor; for example, what did the VAX use for a card punch peripheral? Did any VAX ever control a bank of 24 300 ips tape drives? In that light, no PC platform ever rose to the level of a mainframe, no matter what the folks at Intel called the IA432.
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Well, in terms of raw numbers of peripherals and in terms of RAS, EMC's PC-platform-based Clariion and VNX storage systems definitely blur the lines, as they are embedded PC platforms, running Windows Storage Server on top of EMC's proprietary FLARE operating environment on one of the most highly available systems out there. VNX systems can have upwards of 1,000 dual-attach SAS hard drives on a single pair of Intel Xeon-based storage processors, and one of our Clariions can have 480 drives on its four dual-attach redundant Fibre-Channel back-end loops. And if you have the correct credentials to do so, you can pull up a Remote Desktop on the storage processors and run them as if they were two PCs.

Clariion, incidentally, was part of EMC's purchase of Data General, and was originally the brainchild of none other than Tom West. Yes, that Tom West. His obit: http://www.nytimes.com/2011/05/28/business/28west.html?ref=deathsobituaries&_r=0 (yes, you really do want to read that.)
 
Grandcheapskate said:
True story. One day I am at lunch and the data center experiances a power failure and the UPS doesn't kick in. Everything crashes. I get paged (this was before wide use of cell phones) because they do not know how to restart all the IDMS systems. Why did they call me instead of my manager? They did call him, but he had no idea how to do my job so he told them to page me. I returned to work and restarted all the systems. Later, I went to the data center manager and asked why they did not follow the restart documentation which management demanded I write and which was in their IPL procedure book. The response (are you ready for this?) - you can't expect the operators to read documention when they are trying to restart the system! If it wasn't true, it would not be believable.
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I can sympathize with that. A short while before I went out to pasture, I was asked (told) to attend a staff meeting where the new manager would be introduced and briefly speak. Keeping in mind that 3 highly skilled technical divisions were in the process of being merged, she (her!) proceeded to inform us all that "you need not be an expert in your field to be a manager". It was all down hill from there for me.
 
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Grandcheapskate said:
Hence my inquiry. Was there ever a computer made for home use which basically emulated the IBM/360 family of
computers? A machine which, to the programmer, looked and acted like a mainframe? A machine on which
someone with IBM mainframe experiance could take that knowledge and use it? A machine with an assembler that
looked like a real assembler?

Thanks...Joe
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Joe,
I am going to re-iterate what some one else said else where. Whilst there were PC "add-ons" that were Mainframe compatible non were remotely affordable for home use. As well as Compatable machines there have "always" been software emulations as well. There was the old Don Higgins PC/370 assembler and simulator that would assemble simple 370 MVS type programs. I believe that later it was developed by Microfocus and I think used to implement their PC Cobol suite. Whilst the PC/370 was shareware, the Microfocus stuff was again priced to be cheaper than a mainframe, but only by 10%.

These days there is the Hercules 390 Emulator which is free, but IBM will not licence any software. IBM also produce a Mainframe Emulator for developers but again its thousands of dollars per year, so again not exactly priced for home use...
 
lowen said:
Well, in terms of raw numbers of peripherals and in terms of RAS, EMC's PC-platform-based Clariion and VNX storage systems definitely blur the lines, as they are embedded PC platforms, running Windows Storage Server on top of EMC's proprietary FLARE operating environment on one of the most highly available systems out there. VNX systems can have upwards of 1,000 dual-attach SAS hard drives on a single pair of Intel Xeon-based storage processors, and one of our Clariions can have 480 drives on its four dual-attach redundant Fibre-Channel back-end loops. And if you have the correct credentials to do so, you can pull up a Remote Desktop on the storage processors and run them as if they were two PCs.
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Yeah, but that's SAS--not bus & tag or even SMD. Don't ask me what a mainframe today looks like--I haven't the faintest idea. :) How many 9-track tape drives will the Clarion interface to? How about one of those big STC 9-track library units? You get my drift.

In fact, a low-end notebook interfacing to cloud storage has probably more capacity than all the legacy "mainframe era" data centers ever did. That doesn't make it a mainframe, does it? An IBM 650 would have been considered a "mainframe" back when.
 
g4ugm said:
Joe,
I am going to re-iterate what some one else said else where. Whilst there were PC "add-ons" that were Mainframe compatible non were remotely affordable for home use. As well as Compatable machines there have "always" been software emulations as well. There was the old Don Higgins PC/370 assembler and simulator that would assemble simple 370 MVS type programs. I believe that later it was developed by Microfocus and I think used to implement their PC Cobol suite. Whilst the PC/370 was shareware, the Microfocus stuff was again priced to be cheaper than a mainframe, but only by 10%.

These days there is the Hercules 390 Emulator which is free, but IBM will not licence any software. IBM also produce a Mainframe Emulator for developers but again its thousands of dollars per year, so again not exactly priced for home use...
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I just read a little about the Hercules Emulator on Wikipedia. That sounds like something which would be very interesting to learn and use if I ever want to revive some of my old code as a challenge. It was also interesting to see IBM's MVS operating system, among others, is now public domain software.

Of course, I now realize that without software (such as assemblers, compilers and macro libraries) there's not much I could do with an MVS OS...unless that type of software comes packaged with the OS.

Thanks for that info. I love this forum.

Joe
 
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Chuck(G) said:
Yeah, but that's SAS--not bus & tag or even SMD. Don't ask me what a mainframe today looks like--I haven't the faintest idea. :) How many 9-track tape drives will the Clarion interface to? How about one of those big STC 9-track library units? You get my drift.
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If it's available with Fibre Channel, it can be interfaced. IBM supports several FC-attached tape libraries with their Tivoli Storage Manager; no, those aren't 9-track reel-to-reel with vacuum columns, but they are tape. EMC had some software to do this kind of thing, but it needs another front-end processor to do the fibre-channel to tape interface. EMC does do mainframe to fibre-channel attach software, too, including being able to use Clariion and Symmetra storage as DASD on zSeries. Clariion is the mid-range; Symmetra is the high-end.

In fact, a low-end notebook interfacing to cloud storage has probably more capacity than all the legacy "mainframe era" data centers ever did. That doesn't make it a mainframe, does it? An IBM 650 would have been considered a "mainframe" back when.
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Yeah, it's not about the quantity of the storage; it's about the quality (RAS, again). The big storage boys (NetApp, EMC, IBM, Nimble) don't just throw a bunch of PC SATA drives together and call it an array.
 
Grandcheapskate said:
I just read a little about the Hercules Emulator on Wikipedia. That sounds like something which would be very interesting to learn and use if I ever want to revive some of my old code as a challenge. It was also interesting to see IBM's MVS operating system, among others, is now public domain software.

Of course, I now realize that without software (such as assemblers, compilers and macro libraries) there's not much I could do with an MVS OS...unless that type of software comes packaged with the OS.

Thanks for that info. I love this forum.

Joe
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It may be surprising to note that early releases of IBM operating systems were released as Public Domain, and have always been Public Domain, things take a long time for Copyright to expire. The MVS in common use with Hercules, so MVS 3.8J was supplied by IBM as Public Domain and the folks who originally obtained it also got letters to say it could be re-distributed.

http://cbttape.org/~jmorrison/mvs38j/

In the same way early releases of DOS/370, OS/MVT and VM/370 were released as public domain. The MVT compilers are also public domain and generally they work in MVS and VM. There is a "Turnkey" version of Hercules and MVS available for download here:-

http://wotho.ethz.ch/tk4-/
 
lowen said:
Yeah, it's not about the quantity of the storage; it's about the quality (RAS, again). The big storage boys (NetApp, EMC, IBM, Nimble) don't just throw a bunch of PC SATA drives together and call it an array.
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Sure, but the vagueness of what a "mainframe" means today just blurs the question. The OP asked about IBM S/360, so he's clearly into classic, not vintage stuff. So it's not a matter of computing power--a PDP 11 of 1970 as compared to,say, a contemporaneous 360/95 is a minicomputer-to-a-mainframe comparison.

So what could a model 95 do that a 11/70 couldn't? In other words, what distinguished them? I submit that it was I/O--S/360 (not including the 20 series) had the channel architecture, where the 11 did not. Does a PC with a 360 emulation card have the same I/O capabilities? I don't think you could take a bus-and-tag device and hook it up to a desktop.

It's a complicated question full of shifting definitions and very subjective ones at that. I brought up the Unisys Micro A as another example--the B6800 that it emulates is very definitely a mainframe of its time, but the I/O again, is completely different from the original.
 
Chuck(G) said:
Sure, but the vagueness of what a "mainframe" means today just blurs the question. The OP asked about IBM S/360, so he's clearly into classic, not vintage stuff. So it's not a matter of computing power--a PDP 11 of 1970 as compared to,say, a contemporaneous 360/95 is a minicomputer-to-a-mainframe comparison.
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RAS is still the deal, at least in my opinion. The 11 series just simply didn't have the high-availability features the System/360 did in the same timeframes. Which is why the System 360 architecture, in its System/4 Pi avionics trim, was the fault-tolerant computer chosen for the Space Shuttle.

So what could a model 95 do that a 11/70 couldn't? In other words, what distinguished them? I submit that it was I/O--S/360 (not including the 20 series) had the channel architecture, where the 11 did not. Does a PC with a 360 emulation card have the same I/O capabilities? I don't think you could take a bus-and-tag device and hook it up to a desktop.
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ESCON and parallel (bus and tag) channels are supported by PCI cards in the IBM S/390 Integrated Server; I have one of these here with one of each channel card in it; if you would like pics of those cards and such, I can do that, but it will take a bit of time..... I don't know if the previous generation of PC/370 products supported channel attachments or not. The S/390 IS system is about the same size as the S/390 Multiprise 3000, but the MP 3000 is a 'real' mainframe, whereas the S/390 IS is a 'PC with a P/390 and SSA RAID DASD' where the PC runs OS/2 with the P/390 software stack loaded. To be fair to your statement, the S/390 IS is not a 'desktop' (unless you have a huge desk) but the P/390 cardset could be installed in a 'desktop' and it would run.

As to a direct comparison of the 360/95 to the 11/70, well, they are a decade apart; perhaps a more direct comparison would be a PDP 8e to the 360/95? With 5MB of memory (and over 700MB/s memory bandwidth!) in 1968, the 360/95 was a memory beast in its day. The 8e could address, what, 32KW? (I am not an 8 guru by any means!). The 11/70 could do 4MB in 1975, seven years later. Perhaps an IBM S/360-series expert can chime in on the RAS features of the older models in this series.

It's a complicated question full of shifting definitions and very subjective ones at that. I brought up the Unisys Micro A as another example--the B6800 that it emulates is very definitely a mainframe of its time, but the I/O again, is completely different from the original.
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That's why I used the term 'Mainframe in name only' earlier..... The S/390 IS is one such animal; the MP 3000 in the same case is a real, if small, mainframe.

EDIT: Although, the guy behind http://www.corestore.org/390.htm might disagree with me.....
 
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This is all very interesting and all very new to me.

Can someone just briefly describe the steps you would need to take in order to have your PC run Hercules and an IBM OS?

I'm guessing the first two steps are: (1) load your PC OS (Win98, 2000, etc.) and (2) download and install Hercules. But what do you do from there?

Too bad it doesn't appear there is a public domain IBM OS with XA capability. I did some work using 24 and 31 bit programs and switching between them. Would be nice if I ever took up this project to be able to "play" with all that code.

Thanks...Joe
 
Hercules needs a reasonable modern windows, so officially XP or later, or a modern Linux, or a modern Apple machine. It has also been built on Solaris. The Turnkey-4 download I pointed to includes Hercules and MVS and 3270 terminal emulators. Start with the user guide.....

http://wotho.ethz.ch/tk4-/MVS_TK4-_v1.00_Users_Manual.pdf

there is also the z390 tool, which is a Java based emulation of a 64-bit user mode machine. There is Assembler, Cobol and CICS emulation.

Some people have reported than the zVM evaluation edition will run on Hercules...

http://www.vm.ibm.com/eval/

which gives 24, 32 and 64-bit code support...
 
There's a program called something like "IBM360" from the ancient SIMTEL archives. It seems to include an assembler, but I've never taken a good look at it. Given its age, it probably runs on unvarnished DOS.
 
Chuck(G) said:
There's a program called something like "IBM360" from the ancient SIMTEL archives. It seems to include an assembler, but I've never taken a good look at it. Given its age, it probably runs on unvarnished DOS.
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That's probably the "Don Higgins" PC/370 assembler and simulator I mentioned earlier, PC/370. You can get it from here:-

http://www.scovetta.com/archives/simtelnet/msdos/emulate

or

http://archives.scovetta.com/pub/simtelnet/msdos/emulate/pc370v42.zip

you will need DosBox on a 64-bit windows. I found some history here:-

http://don-higgins.com/pc370.htm

The assembler/debugger seems much nicer than I remember...
 
I went to my archive drawer and dug out a 360K floppy--you're correct--it's the Higgins version from 1985--version 1.0. Seems to run just fine on an AMD64 Ubuntu running DOSEMU. I was impressed with the size of the thing--about 150K .ARC file, documentation and programs. Of course, it's not full-featured, but there's enough there for learning purposes. My archive name is IBM370.ARC.
 
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