[HN Gopher] The Mainframe Six (2022)
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The Mainframe Six (2022)
Author : rbanffy
Score : 49 points
Date : 2025-10-24 16:01 UTC (7 hours ago)
(HTM) web link (arcanesciences.com)
(TXT) w3m dump (arcanesciences.com)
| kps wrote:
| Needs a catchy name.
|
| - 1960s: IBM and the Seven Dwarfs [Univac RCA NEC GE Honeywell
| CDC Burroughs]
|
| - 1970s: IBM and the BUNCH [Burroughs Univac NEC CDC Honeywell]
| rbanffy wrote:
| Let's see...
|
| IBM and the FUNHA?
|
| IBM and the HU-FAN?
| bob1029 wrote:
| Mainframe is still my favorite architecture for F100 use cases.
| You'll note how your grocery stores, debit cards, gas stations,
| toll roads, et. al., continued to function ~fine during the AWS
| outage this week.
|
| The biggest problem with the mainframe conversation is the TCO
| paradox that it creates. For the average CTO, the prospect of
| paying IBM millions of dollars up front is absolutely a non-
| starter. They just can't get beyond this aspect. It doesn't
| matter if you promise them a genie with unlimited wishes at the
| end - and this isn't too far off from what you actually get in
| some cases. The initial sticker shock is simply a bridge too far.
|
| The savings you see only manifest after years of not doing the
| other things. This kind of savings is usually invisible to the
| business leaders. You have to make a really big leap of faith and
| have a lot of good mentors and leaders around you to execute on
| this kind of architecture. It is also essential to lead the
| technology people along the path of best practices. I've seen a
| large corporation justify moving away from mainframe after
| allowing its employees to load applications on it that are wildly
| unsuitable for that kind of compute platform. Think things like
| SalesForce and GitHub Enterprise - "See, it runs like ass and IBM
| is billing us like crazy! - we _need_ to get off mainframe ".
| p_l wrote:
| You don't have to pay upfront, IBM in fact _prefers you don 't_
|
| Leasing, or frank out renting aka "cloud" that just happens to
| be IBM is the preferred form, especially as they can sell you
| on usage based pricing (good if your workload follows common
| pattern of spiking at end of month)
| UltraSane wrote:
| It seems very strange to pay for usage on hardware only you
| can use.
| p_l wrote:
| But profitable to IBM, and counts as OpEx not CapEx for
| accounting. A bit like cloud. But if you want they will
| ship it to you, or just setup a VPN or even a more
| dedicated connection (say, MPLS) to one of their
| datacenters. Or even sell it to you cloud style, running on
| LPAR/zVM.
|
| They also tend to send you a more filled out mainframe
| (more CPU, more memory) so you can be flexible with
| utilization or "pay on demand" for more occassionally.
| adamzwasserman wrote:
| A hacker classic: https://www.hactrn.net/sra/vaxen.html
| watersb wrote:
| # VAXen, My Children, Just Don't Belong In Some Places
|
| _The trouble started when the Chief User went to visit his
| computer and its VAXherd._
|
| _He came away visibly disturbed and immediately complained
| to the ELFI 's Director of Data Processing that, "There are
| some _very strange_ people in there with the computers."_
|
| _Now since this user person was the Comptroller of this
| Extremely Large Financial Institution, their VAX had been
| promptly hustled over to the IBM data center which the
| Comptroller said, "was a more suitable place." The people
| there wore shirts and ties and didn't wear head bands or
| cowboy hats._
|
| Oh my. It's 2025 and I'm just reading this for the first
| time.
|
| In 1998, we were getting some large consumer brands on the
| World Wide Web for the first time. One of our customers had a
| Director of Security who didn't trust us. When he came out to
| see our data center, our web services, he trusted us even
| less. The guys wore ties that day, but the long hair didn't
| help.
|
| It was really too bad; the Security Director was not wrong
| about many aspects of the whole idea and he was able to get
| executives in our parent company to realize that security
| best practices would require some structural changes on our
| part; we couldn't just buy a net appliance to take care of
| it. Having that client on board with that Security Director's
| input could have been a productive experience. But he didn't
| like what he saw, and that particular project was canceled.
|
| Given the rather percussive events in this tale of The Little
| VAX and the DataCenter, perhaps that was all for the best.
| fock wrote:
| I guess for IMS/CICS/TPF/... the IBM mainframe is a just fine
| appliance compared to the alternatives. While not exactly
| transaction processors, SAP HANA, Oracle Exadata and co. all
| market themselves towards the same customer groups; SAP even
| sells full banking systems for medium-sized banks.
|
| Your point that TCO is lower than a well executed alternative
| seems very dubious to me though. Maybe lower than cloud and
| also certainly lower than whatever crap F100-consultants sold
| you, but running database unloads with basic ETL for a few
| dozen terrabytes per month creating a MSU-bill in the millions
| is just ridiculous. The thing which probably lowers the TCO is
| that EVERY mainframe-dev/ops-person in existence is essentially
| a fin-ops-expert formed by decades of cloud-style billing. Also
| experience on a platform where your transaction processing
| historically has KB-range size limits, data-set-qualifiers are
| max. 44 chars, files (which you allocate by cylinders) don't
| expand by default and whatever else you miss from your 80ties
| computing experience naturally leads to people creating
| relatively efficient software.
|
| In general even large customers seem to agree with me on that
| (see Amadeus throwing out TPF years ago) with even banks mostly
| outrunning the milking machine called IBM. What is and will be
| left is governments. Captured by inertia and corruption (at the
| top) and being kept alive by underpaid lifelong experts (at the
| bottom) who have never seen anything else.
|
| > during the AWS outage this week.
|
| Also the reliability promises around mainframes are
| "interesting" from what I've seen so far. The (IBM) mainframe
| today is a distributed system (many LPARs/VMs and software
| making use of it) which people are encouraged to run on maximum
| load. Now when one LPAR goes down (and might pull down your
| distributed storage subystem) and you don't act fast to drop
| the load you end up in a situation not at all unlike what AWS
| experienced this week: critical systems are limping on, while
| the remaining workload has random latency spikes which your
| customers (mostly Unix systems...) are definitely going to
| notice...
|
| The non-IBM-way of running VMs on a Linux box and calling it a
| mainframe just seems like a scam if sold for anything but
| decommissioning. So I guess those vendors are left with
| governments at this point.
| imglorp wrote:
| > ... continued to function ~fine during the AWS outage this
| week.
|
| Isn't any given mainframe stuff one backhoe or flood away from
| its own outage? What's their redundancy and DR plan look like?
| It's not like they have AZ's and regions, more like a warm
| replica data center, right?
| bob1029 wrote:
| > What's their redundancy and DR plan look like?
|
| I toured a facility that utilized Parallel Sysplex / GDPS CA.
| This offers true RTO = RPO = 0. You could take a fire axe to
| any piece of hardware in the building and it would have zero
| effect. For catastrophic events, the guarantees relax a
| little bit, but they're still very strong. Someone breaking
| an entire fiber vault or setting half the datacenter on fire
| would still not compromise operations in this facility. It's
| essentially two datacenters in one, much like how an AWS
| region works with multiple AZs. Each side of the facility is
| entirely independent. Somewhere inside a mountain in Colorado
| a 3rd set of machines is passively replicating everything as
| well.
|
| The most resilient mainframe solutions involve a purpose
| built facility. The cool thing about the mainframe is that it
| isn't very big. You can get do a _lot_ of damage with what is
| effectively just 4 racks of hardware. You 'll probably have
| another 10-20 racks worth of HSMs, firewalls, VPN
| concentrators, UPSes, etc. Most of the infrastructure is to
| support the mainframe. So, the facility doesn't actually have
| to be very large. It just needs to be in a _really_ good
| location and built like a bunker.
| UltraSane wrote:
| The datacenter my company rents racks in has a IBM
| mainframe in it along with a rack for storage and a rack
| for backup. Very clean and also very expensive.
| UltraSane wrote:
| What is the training pipeline for new mainframe operators?
| Anyone can create an account on AWS and learn it but for z\OS
| it is much harder.
| Aloha wrote:
| What about https://en.wikipedia.org/wiki/Stratus_VOS
|
| It certainly looks mainframe like to me
| drtournier wrote:
| I just discovered that 90% of all credit card activity still rely
| on mainframes https://www.mordorintelligence.com/industry-
| reports/mainfram...
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(page generated 2025-10-24 23:01 UTC)