

All you have ever wanted to know about Linux on the mainframe - Garbage
http://www.zdnet.com/news/all-you-have-ever-wanted-to-know-about-linux-on-the-mainframe/6200400

======
pnathan
I would really enjoy getting the chance to hack on a mainframe. I have the
idea that 40 (50?) years of continuously developed OS from OS/360->today must
be something really amazing to use and to work with. But, last time I looked
it was nearly impossible to get a login to one.

~~~
cosgroveb
I forgot to mention that there are emulators out there. I have never used one
but here's one from a quick google search:
<http://en.wikipedia.org/wiki/Hercules_(emulator)>

When I was in school, IBM occasionally had z/OS programming contests and would
provide an environment for student competitors.

~~~
bdb
Hercules is cool -- I last goofed around with it almost 10 years ago, but it
was complete enough then to run VM/370 and MVS/370. If you're interested,
start here: <http://www.cbttape.org/vm6.htm> and <http://www.bsp-
gmbh.com/turnkey/>

------
spitfire
Why isn't Linux on the mainframe taking off? Mostly because it costs $75,000
per processor I'm guessing.

Not including the rest of the mainframe. Plus support. and you can't scale it
in realtime.

Mainframes are absolutely fabulous creatures capable of amazing feats. But the
culture/pricing around them has not kept up with the times. I wish it would
have because a small mainframe would be a good choice for many purposes.

~~~
jacques_chester
> and you can't scale it in realtime.

What do you mean by this?

You can't resize the images? Sure you can.

You can't add more virtual servers quickly? Of course you can. I'm told by a
mainframe-operator acquaintance that Linux on z/VM can spin up hundreds of
instances per minute.

You can't get the mainframe to run faster? Tosh. IBM generally oversupply you
with CPU capacity; if you need more you can ring up and they will reconfigure
them remotely to add CPU power.

Other advantages: a zSeries mainframe is extremely reliable, IBM's service is
expensive but extremely thorough and unlike other virtual server environments
it enforces partitioning at a hardware level, and much more completely. No
more mysterious performance variation due to bursty neighbours.

------
prodigal_erik
> virtualizing servers by factors in the hundreds

Yeesh. The way I've heard it, this is due to a peculiar approach in mainframe
development. Programs tend to assume isolated use of dedicated hardware, so
they have to resort to creating ludicrous numbers of virtual mainframes rather
than letting the programs coexist and interact within a single kernel.

~~~
whatusername
"Programs tend to assume isolated use of dedicated hardware, so they have to
resort to creating ludicrous numbers of virtual mainframes rather than letting
the programs coexist" ----> Sounds like Windows VMWare/HyperV deployment
justifications. :)

There is a supposed higher security in zOS partitioning -- but I have no idea
what EAL Levels really mean:
<http://en.wikipedia.org/wiki/Evaluation_Assurance_Level>

------
wtracy
If one had too much cash sitting around and wanted to play with a low-end
mainframe, what would be the ballpark cost to get one? Half a million?

Yes, I'm aware that IBM wants you to lease mainframe hardware rather than
actually buy it.

~~~
bdb
If you had a truck and a bunch of free time, say, $499?

[http://cgi.ebay.com/IBM-S-390-G5-Parallel-Enterprise-
Server-...](http://cgi.ebay.com/IBM-S-390-G5-Parallel-Enterprise-
Server-/300533094844?pt=COMP_EN_Workstations&hash=item45f92b19bc#ht_662wt_907)

The interesting thing about mainframe hardware is that it's designed to last
forever, so the "old" stuff (which really means "brand new" stuff in mainframe
terms) is still interesting.

