Will z/OS be obsolete in 5 years?

[Jon Perryman]

IBM RHEL announced it's move to closed source (IBM RedHat Enterprise Linux). With some changes, DB2, RACF and other z/OS products could run in Linux on z16 in one sysplexed Linux image. We know it's possible because IBM moved Unix and TCP into z/OS. IBM RHEL said closed source would force non-paying customers to buy RHEL licenses but this makes no sense. Something else must be in play.
I created a survey at https://forms.gle/ZTPXsDJo8Z4H93sv7 to gain insights into IBM's decision to close source RHEL. You can skip the survey if you don't want to take it and view the survey results through this website. Feel free to pass this along.
 I think IBM wants to integrate z/OS products to retain their investments and expand their customer base..
Why is the z/OS community ignoring IBM RHEL closed source? Are software vendors preparing their products for Linux? 

[James H]

Wow, thats interesting. I will have to research this more.
My first thought is this is just a move by IBM to get more money.

J-|

[David Kreuter]

Stick it in a Linux container in a Linux virtual machine under z/VM. Done.
________________________________
From: IBM Mainframe Assembler List <ASSEMBL...@LISTSERV.UGA.EDU> on behalf of James H <tarr...@GMAIL.COM>
Sent: Tuesday, July 18, 2023 8:52:01 PM
To: ASSEMBL...@LISTSERV.UGA.EDU <ASSEMBL...@LISTSERV.UGA.EDU>
Subject: Re: Will z/OS be obsolete in 5 years?

[Jon Perryman]

IBM is driven by profits but a single sysplexed Linux server could have 7,000 cores. Google has 5,500,000 Linux servers with an army to maintain it. 25 cores is less cores than the smallest IBM z16 (max 39 with 39 cores enabled). Google admits they have equipment failing all the time. They have a disk drive shredder on site to keep up with the disk drive failures.
Linux is designed for small computers.

[Jon Perryman]

Linux in VM is a non-starter for hyperscale Linux computing. You might as well by PC servers.

[Steve Thompson]

Linux in VM is a non-starter for hyperscale Linux computing. You might as well by PC servers.

What is hyperscale Linux? I've been involved in LPARs of z/VM running multiple Linux servers in SSI pairs for hot fail over. So I am curious what you mean by this.

Looking this up, I read a lot of word salad, and salespeople/marketeers that don't understand (or flatly ignore that Cloud is someone else's data center), so their definitions are, really, word salad.

Steve Thompson

[Jon Perryman]

When you start questioning Linux terminology, the whole story starts to fall apart. Hyperscale has meaning beyond marketing and programmers use it as to boast about their skill. It happened to be the one that popped into my head. I could have said bigdata, cloud, clusters or boat load of other terms that are equally different to different people. The sad fact is that Linux has a lot of terminology that average people are exposed to because there are so many solutions to the same problem. 
Maybe you should talk to a Google programmer about chunk locks for the Google Filesystem that has been replaced by Google Collosus. Cobol programmers don't need to know about chunk locks because it's hidden by update for a record,
Hyperscale is a configuration that meets high demands of shifting workload and as you say is used a lot in reference to cloud computing. IBM can do this with hardware and z/OS software whereas Linux is a software solution. In Linux, maybe you do it by virtualization or by repurposing one or more computers. z hardware and z/OS gives you a lot more options that are simpler (e.g. WLM, LPAR/CPU defs, Hardware disk replication).

[Ian Worthington]

Is this correct?  My understanding is that the source is still available but now only to customers in order to prevent downstream suppliers from using rhel as their base.
Of course I've slept since I saw this discussion so caveat emptor...


Best wishes / Mejores deseos /  Meilleurs vœux

Ian ...

[dave....@gmail.com]

> -----Original Message-----
> From: IBM Mainframe Assembler List <ASSEMBL...@LISTSERV.UGA.EDU>

> On Behalf Of Jon Perryman
> Sent: Wednesday, July 19, 2023 1:47 AM
> To: ASSEMBL...@LISTSERV.UGA.EDU
> Subject: Will z/OS be obsolete in 5 years?
>
> IBM RHEL announced it's move to closed source (IBM RedHat Enterprise Linux).
> With some changes, DB2, RACF and other z/OS products could run in Linux on
> z16 in one sysplexed Linux image.

A heck of a lot of changes, for a start z/OS is EBCDIC and Linux is some modern descendant of ASCII ...
... and if they ran on Linux on Z than why won't they run on Linux on some other platform, surely only the largest players need Z..
.. although Amazon, E-Bay, Microsoft Cloud Services seem to manage without it....

> We know it's possible because IBM moved
> Unix and TCP into z/OS.

Did they really "move" TCP/IP & UNIX?

The original TCP/IP in MVS came from VM and was written in PASCAL so not UNIX based.
From what I remember USS was written from scratch. The entry in Wikipedia seems to confirm this, it says :-

https://en.wikipedia.org/wiki/UNIX_System_Services

" ... It is the first UNIX 95 to not be derived from the AT&T source code. "

So freshly created, not moved ....

> IBM RHEL said closed source would force non-paying
> customers to buy RHEL licenses but this makes no sense.

As a statement, it makes perfect sense. If all else is equal it means they will receive money for something they don't at present.

> Something else must be in play.

Ah, a conspiracy theory. Of course other things are in play, but I believe they are more about protecting the image that "z" is different, in a good way to other platforms than moving zOS to Linux.
In fact moving components from z/OS into Linux would, I believe devalue them and reduce their USPs....

> I created a survey at https://forms.gle/ZTPXsDJo8Z4H93sv7 to gain insights into
> IBM's decision to close source RHEL. You can skip the survey if you don't want to
> take it and view the survey results through this website. Feel free to pass this
> along.
> I think IBM wants to integrate z/OS products to retain their investments and
> expand their customer base..

Why do that. It would result in a huge loss of hardware revenue. IFLs for running UNIX are much cheaper than the CPUs needed to run z/OS.

> Why is the z/OS community ignoring IBM RHEL closed source?

Because its not relevant.? Is it ignoring it?

> Are software vendors preparing their products for Linux?

I assume that those that are relevant already have, but for any that were using free RHEL on Z to develop will now face extra charges.
Will their prices go up?
Will they exit the Z market.

... one last point, my question would be, is this likely to back-fire on IBM?

Will it deter any one in a University or Academia from buying Z if they have to pay, or will IBM offer them a discount of 100%?

Dave

[Tom Marchant]

The terms of the GNU General Purpose License do not allow the source to be restricted in any way. The Linux kernel is licensed under GPL v2
https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
AFAIK, most of the rest of the GNU operating system (colloquially known as "Linux", although Linux is actually just the kernel) is licensed under GPL v3
https://www.gnu.org/licenses/gpl-3.0.en.html

--
Tom Marchant

On Wed, 19 Jul 2023 07:03:05 +0000, Ian Worthington wrote:

>Is this correct?  My understanding is that the source is still available but now only to customers in order to prevent downstream suppliers from using rhel as their base.
>Of course I've slept since I saw this discussion so caveat emptor...
>

> On Wednesday, July 19, 2023 at 02:47:32 AM GMT+2, Jon Perryman <jper...@pacbell.net> wrote:
>

>> IBM RHEL announced it's move to closed source (IBM RedHat Enterprise Linux). With some changes, DB2, RACF and other z/OS products could run in Linux on z16 in one sysplexed Linux image. We know it's possible because IBM moved Unix and TCP into z/OS. IBM RHEL said closed source would force non-paying customers to buy RHEL licenses but this makes no sense. Something else must be in play.

>>I created a survey at https://forms.gle/ZTPXsDJo8Z4H93sv7 to gain insights into IBM's decision to close source RHEL. You can skip the survey if you don't want to take it and view the survey results through this website. Feel free to pass this along.
>> I think IBM wants to integrate z/OS products to retain their investments and expand their customer base..

>>Why is the z/OS community ignoring IBM RHEL closed source? Are software vendors preparing their products for Linux? 

[Ian Worthington]

That's what I had though, but apparently it's not correct.  In fact, for many years IBM has withheld its own changes to GCC for private sale to its own customers, apparently quite legally.
(Caveat:  The absence of any yacht clearly indicates I am not a lawyer.  Nor do I play one on TV.)

Best wishes / Mejores deseos /  Meilleurs vœux

Ian ...

[Paul Rogers]

On Wed, Jul 19, 2023 at 2:35 PM Ian Worthington <
00000c9b78d54ae...@listserv.uga.edu> wrote:

> That's what I had though, but apparently it's not correct. In fact, for
> many years IBM has withheld its own changes to GCC for private sale to its
> own customers, apparently quite legally.
> (Caveat: The absence of any yacht clearly indicates I am not a lawyer.
> Nor do I play one on TV.)
> Best wishes / Mejores deseos / Meilleurs vœux
>
> Ian ...
>

For those who are curious, the good folks at https://lwn.net/ have been
covering some of these issues.

I believe that these are the articles (most of which I haven't even glanced
at)::
Red Hat cutting back RHEL source availability:
https://lwn.net/Articles/935592/
AlmaLinux's response to Red Hat's policy change:
https://lwn.net/Articles/935918/
Kuhn: A Comprehensive Analysis of the GPL Issues With the Red Hat
Enterprise Linux (RHEL) Business Model: https://lwn.net/Articles/936127/
McGrath: Red Hat’s commitment to open source:
https://lwn.net/Articles/936405/
Brockmeier: Red Hat and the Clone Wars III: The dawn of CentOS:
https://lwn.net/Articles/937317/
AlmaLinux to diverge (slightly) from RHEL:
https://lwn.net/Articles/938165/

Please be sure to enjoy the day -- we won't get another chance! ;-)

Paul

[Tom Marchant]

Do you have evidence that IBM has withheld their changes to GCC?

--
Tom Marchant

[Ian Worthington]

Yes..  But, as I said, I believe that they are allowed to do so.

Best wishes / Mejores deseos /  Meilleurs vœux

Ian ...

[Schmitt, Michael]

I Am Not A GPL Expert but...

My understanding is...

* A company can create closed source products using the GCC toolchain
* A company can make changes to the GCC toolchain, and then use it to create closed source products (but maybe this is different in GPL3)

But

* If you sold a compiler that was derived from GCC source now your product is open source and you must make the source available

* Same if you found some cool logic in the GCC source and incorporated that source code into your source.

So if IBM is changing GCC and the improved GCC in RHEL as closed source, that's bad. But if IBM is changing GCC and using it to compile other things, that's OK.

I think.

[Jon Perryman]

> Do you have evidence that IBM has withheld their changes to GCC?

While hardware specific changes can be maintained with GCC, is there a real purpose? I doubt that IBM modifies anything that affects generic GCC.

[Ian Worthington]

You think, Michael, the same as I used to think.  But I'm informed that the changes to rhel open-sourcing of rh's secret sauce are legal under the gpl and, thus, changes to the gcc compiler do not have to be made freely available either.

I don't claim to understand this.

Best wishes / Mejores deseos /  Meilleurs vœux

Ian ...

[Tom Marchant]

Yes? That's all you have? Secret claims have no value.

Your belief doesn't agree with the GPL version 3, which is the license for GCC.
https://www.gnu.org/licenses/gpl-3.0.en.html

<quote>
5. Conveying Modified Source Versions.

You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:

a) The work must carry prominent notices stating that you modified it, and giving a relevant date.
b) The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to “keep intact all notices”.
c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.
d) If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.
</quote>

"Released under this License" includes providing source.

Providing source does not necessarily mean making it available to anyone.

<quote>
6. Conveying Non-Source Forms.

You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:

a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.
b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.
c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.
d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.
e) Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.
</quote>

--
Tom Marchant

On Wed, 19 Jul 2023 20:42:52 +0000, Ian Worthington wrote:

>Yes..  But, as I said, I believe that they are allowed to do so.
>
>

>Best wishes / Mejores deseos /  Meilleurs vœux
>
>Ian ...
>

> On Wednesday, July 19, 2023 at 10:36:08 PM GMT+2, Tom Marchant <000000a69b48f3b...@listserv.uga.edu> wrote:
>
> Do you have evidence that IBM has withheld their changes to GCC?
>

>--
>Tom Marchant
>

>On Wed, 19 Jul 2023 19:35:09 +0000, Ian Worthington wrote:
>

[Ian Worthington]

Indeed the changes I'm aware of do not affect generic gcc but a specific ibm product that requires a custom gcc for which ibm will sell you the custom changes.

Best wishes / Mejores deseos /  Meilleurs vœux

Ian ...

[Jon Perryman]

> surely only the largest players need Z.

When should Google have moved its 5,500,000 servers to z? A mechanic only need 2 tools. A hammer when something should move but won't and duct tape when it moves but shouldn't. Medium players should be using z servers. One IBM z16 can have 2,500 PCIe slots compared to the 8 that the biggest non-IBM motherboards. If Linux were efficient, then more than 8 PCIe slots would be needed. Manufacturers would build it if there were demand. Surely Google alone with 5,500,000 servers would make it profitable.

> although Amazon, E-Bay, Microsoft Cloud Services seem to manage without it....

What alternative do these companies have? Their employees refuse to become z/OS programmers where they don't have control over security, optimization and every other aspect of the computer. They feel it's better to use Big-O instead of relying on Intune to identify program bottlenecks. IBM programmers are business experts whereas Linux programmers are computer experts proud of the tools they use and build.

> Did they really "move" TCP/IP & UNIX?

 If it came from VM, then why did use USS dubbing and a USS RACF segment? TCP/IP 3.1 was from BSD Unix and it was very apparent. 3.2 was better but the 3.4 rework made a world of difference.

As for USS, the wiki you mentioned says "not be derived from the AT&T source code".  USS was derived from something which I think was BSD. Some of the kernel would be rewritten but there is a lot of code they wouldn't rewrite and obtained from somewhere. The kernel is a small part of what we think of as Unix and many parts were retained. Shells, script and more was carried over from somewhere.

>>  I think IBM wants to integrate z/OS products to retain their investments and

>> expand their customer base..


> Why do that. It would result in a huge loss of hardware revenue. 
> IFLs for running UNIX are much cheaper than the CPUs needed to run z/OS.

IFL's are discounted because Linux runs poorly on z16. Every CPU in a z16 is the same so IBM will never discount an entire z16 just for Linux. Linux customers don't want z/OS so z16 is not an option for Linux only customers. If IBM wants to increase the z16 market share, they must make RHEL perform as well as z/OS and charge full price for CPUs.

IBM has a huge investment in z/OS software that if compatible with RHEL would bring in the same revenues as z/OS. 

[Rob van der Heij]

On Thu, 20 Jul 2023 at 02:15, Jon Perryman <jper...@pacbell.net> wrote:


> > Why do that. It would result in a huge loss of hardware revenue.
> > IFLs for running UNIX are much cheaper than the CPUs needed to run z/OS.
>
> IFL's are discounted because Linux runs poorly on z16. Every CPU in a z16
> is the same so IBM will never discount an entire z16 just for Linux. Linux
> customers don't want z/OS so z16 is not an option for Linux only customers.
> If IBM wants to increase the z16 market share, they must make RHEL perform
> as well as z/OS and charge full price for CPUs.

It would be interesting to see your evidence of IBM Z not performing well
with Linux. That was probably true 20 years ago with the early CMOS CPUs,
but not anymore. My experience is that z16 CPUs are very effective running
enterprise application workloads in Linux at high levels of utilization.
IBM contributions to the various open source projects like the gcc
toolchain let you generate code that is optimized to take advantage of the
CPU architecture, the zlib compression library takes advantage of the
built-in compression instruction, the openssl libraries exploit CPACF
instructions when compiled for s390x, java applications in Linux and in
z/OS compete well with other platforms, the entire machine learning suite
exploits the built-in neural network instruction of the Telum chip.

Pricing is too complicated for techies. You get a CPU rather than IFL to
run licensed IBM software, which suggests that the price difference for the
hardware is for operating system software revenue not recovered by MLC. The
same holds for the other specialty engine types that run workloads that do
not have to contribute to the operating system software revenue; java runs
as fast on a zIIP as on a CP, so that's no reason for the rebate on a
zIIP. If you don't need any licensed IBM software to run, you get a machine
with only IFL.

Rob

[Ian Worthington]

There is no secret, see https://www.ibm.com/docs/en/ztpf/2022?topic=tasks-build-gnu-compiler-collection-ztpf-system, third bullet point.  Have your check book handy when you call.


My prior belief also didn't agree with those who are saying the rh move is legal under the gpl.  But, as I keep saying, I am NAL.

Best wishes / Mejores deseos /  Meilleurs vœux

Ian ...

[Tom Marchant]

That is your evidence that "for many years IBM has withheld its own changes to GCC for private sale to its own customers"?

LOL!

--
Tom Marchant

[Tom Marchant]

You are wrong again. https://www.ibm.com/linuxone
The latest iteration is version 4, a z16. The first was a z13.
See also https://en.wikipedia.org/wiki/Linux_on_IBM_Z

--
Tom Marchant