
Mainframes as a lifestyle choice - k4rtik
http://wozniak.ca/mainframes-as-a-lifestyle-choice
======
emersonrsantos
You can run IBM old OS/360 and many other mainframe OSes using hercules-390
[1], which emulates old and new mainframe architectures and has an active
community [2].

[1] [http://www.hercules-390.eu](http://www.hercules-390.eu)

[2]
[http://groups.yahoo.com/group/bercules-390](http://groups.yahoo.com/group/bercules-390)

------
snaky
> It's surprisingly easy to cross the border of native z/OS and the USS
> border. In fact, there's no border there at all. z/OS is one operating
> system with two different interfaces. So apart from normal problems and
> hiccups, you'll probably find that the biggest problem accessing the various
> services will be getting used to the difference in vocabulary between USS
> and native z/OS.

[http://www.ibm.com/developerworks/aix/library/au-
bordercross...](http://www.ibm.com/developerworks/aix/library/au-
bordercrossing/)

------
insulanian
> Part of the reason I took the job ... because I have a fascination with
> older computer technology.

I was also thinking about going the mainframe route, also because general
impression is that the mainframe developer earns big bucks. However, when I
started exploring the job offers I was surprised that salaries were not that
high at all.

So why is that impression still around, and do mainframe developers really
earn significantly more money than a full stack enterprise web developer?

~~~
zhte415
Mainframe is possibly the most offshored field there is in enterprise
technology. There are masses of roles in India and to a lesser extent China
and Phillipines where is offers a stable decent paying career for these
countries. That's where the base-line and critical mass of roles are.

~~~
coleca
Very true. Because these skills are in high demand, my experience has been
that employee turnover in the mainframe sector offshore is extremely high. We
had a tremendous problem retaining offshore mainframers through the big BPO
companies like Wipro, Cognizant, US Technologies, etc. Go through the effort
to train them up, and they would get poached in no time because their skills
were in such high demand, and the training cycle starts over again.

~~~
zhte415
Turnover can be high, often depends on industry and country.

I know/do banking with staff in China, around 300 mainframe engineers, with
average tenure around 5 years, which is miles ahead of India. If you'd like
pointers for mainframe in China, drop me a mail.

------
digi_owl
The more i learn about mainframes (and minicomputers) the more i feel that the
PC world is basically rediscovering old ideas as ICs become ever more potent.

~~~
dboreham
Not necessarily rediscovering, just re-implementing.

~~~
dbcurtis
Ha, ha, no.

I worked as a CPU logic designer on several mainframes of different
architectures before moving to Sili Valley. The "look what I just invented"
arrogance I encountered astounded me. When I said something like: "You know,
Seymour Cray invented that around 1959, right?" the cognitive dissonance was
more than they could handle -- I was usually ignored. So, no, they aren't re-
implementing, they are genuinely re-creating history and being proud of
themselves for it.

~~~
BoorishBears
Can you give an example?

~~~
rbanffy
Having dedicated computers to control peripherals (like a RAID controller or a
network card).

To be fair, Atari and Commodore computers already had that.

~~~
wglb
It actually predates that. The CDC 3500 series had a separately programmable
I/O controller.

And the marvelous 1403 printer would often be driven by a 1401.

------
rdtsc
Speaking of mainframes, my favorite talk on hacking IBM mainframes:

[https://www.youtube.com/watch?v=Xfl4spvM5DI](https://www.youtube.com/watch?v=Xfl4spvM5DI)

------
snaky
By the way, z/OS is not the only way to run IBM mainframes. There's TPF
(Transaction Processing Facility) "because a real operating system is too high
level and therefore too slow for real transaction processing needs". Current
users of TPF include Sabre, VISA, American Airlines, American Express, HP
SHARES (formerly EDS), Holiday Inn, Alitalia, KLM, Amtrak, Marriott
International, Travelport, Citibank, Citifinancial, Air Canada, Delta Air
Lines, Japan Airlines and many others.

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PhasmaFelis
What exactly is a "mainframe" in a modern sense? I thought it exclusively
referred to old-fashioned big iron. Is it a cluster? Or are we actually
talking about quarter-century-old monoliths running ancient, indispensable
code?

~~~
mastax
[https://en.wikipedia.org/wiki/IBM_mainframe](https://en.wikipedia.org/wiki/IBM_mainframe)

These are completely disconnected from commodity hardware. They are
descendents of System/360, with a completely custom architecture and
"mainframe processors" which only run specific types of code (Java, XML, DB2).

Or that's what I gather from wikipedia anyway.

~~~
sitharus
sort of. The run z/Architecture CPUs which implement a lot of backwards
compatibility.

In the old days you had various modules you connected with dedicated CPUs for
certain tasks, you'd pay more for them. These days they have a bunch of CPUs
and the amount of money you pay IBM determines what those CPUs can do.

There's no physical difference between the Linux CPU, the DB2 CPU and the Java
CPU, they're all the same as the main CPUs. IBM just charge you more for
general purpose CPUs.

~~~
PeterisP
Ahh, I recall that we ordered an upgrade of the system hardware because we
needed 4 more CPUs, and this was accomplished by sending a code that unlocked
extra CPUs that had been sitting in our basement all along since the day they
installed that system.

~~~
stillworks
IBM do the same for P series as well. You get the privilege of purchasing an 8
core server but you only get the rights to use 4 cores. It's your
responsibility to pay IBM when comes the time to be able to use all the 8
cores. Organized crime of sorts... like democracy

~~~
rbanffy
Actually, if the prices are pre-agreed, it's a sweet deal. If I have a big box
serving my users, being able to enable additional on premises capacity in
minutes is nice.

Last time I did it, Dell took several weeks to deliver the new machine.

~~~
stillworks
We didn't try but being speaking with the vendor it seemed that enabling extra
cores could take about a week from raising a purchase order to the activation
code coming through. Maybe larger customers who run hundreds of these may have
a quicker turn around time dealing directly with IBM.

And it's not that IBM deliver an entire server like in your case. For most
practical applications, it's merely the case of adding CPUs to the pool of
CPUs available to the PowerVM hypervisor. If you need to provision additional
memory or IO, that needs to be accounted in as well.

That hypervisor is weird on it's own. It's part firmware part software.

If you have big box serving your users who solely rely on CPU cycles then yes,
it's a sweet deal. And consider yourself very lucky if you have users who will
immediately see better performance if you throw more CPU cycles at them.

~~~
rbanffy
I remember one case where the activation code was in a sealed envelope. If
used, the machine would acknowledge that through its direct line with IBM and
billing would proceed. The unlocked resources would become available
immediately.

That was in the early 90's and a lot could have changed since then.

------
gaius
Curious about his point about virtualisation; sure you can't run a VM locally
but those mainframe OSs have had excellent support for VMs since the 1960s and
are still in many ways far ahead of more mainstream hypervisors.

~~~
83457
He was talking about local development environment.

~~~
gaius
So why not just get himself a few dedicated VMs on the mainframe? Those things
can supports thousands at a time...

------
pella
And has a Golang Port !!!

"Building Go for Linux on z System"

[https://github.com/linux-on-ibm-z/docs/wiki/Building-
Go](https://github.com/linux-on-ibm-z/docs/wiki/Building-Go)

~~~
snaky
There's more

> The HostBridge JavaScript Engine (HB.js) is server-side JavaScript for CICS®
> applications and IBM z Systems™ data assets

> HB.js runs inside CICS and supports:

> CICS terminal-oriented (visual) transactions (Orchestrate CICS terminal-
> oriented transaction micro flows as single services)

> BMS, non-BMS, 3270, and CA application types

> COMMAREA (non-visual) programs (Orchestrate and aggregate transactions,
> programs (e.g., COMMAREA), and data into single composite services)

> DB2®, VSAM™, DL/I, Datacom®, and other data assets

> Connectivity via HTTP, LINK/EXCI, Enhanced WebSphere MQ Extended Multi-
> Region Operation (MRO)

[https://www.hostbridge.com/index.php/products/javascript-
web...](https://www.hostbridge.com/index.php/products/javascript-web-services-
CICS-zos)

------
R_haterade
Just, why...

~~~
oarsinsync
> Part of the reason I took the job was the opportunity to get paid to work on
> compilers, but also because I have a fascination with older computer
> technology.

It may be worth re-reading the article.

~~~
R_haterade
You are right, I shouldn't question this guy's fascination with any tech.
Especially if it's something that he can love, and do for good money.

Still, mainframes...

------
Andys
They're good for drying undies

