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Microsoft Windows, On a Mainframe 422

Posted by timothy
from the operating-systems-plural dept.
coondoggie writes with an excerpt from Network World: "Software that for the first time lets users run native copies of the Windows operating systems on a mainframe will be introduced Friday by data center automation vendor Mantissa. The company's z/VOS software is a CMS application that runs on IBM's z/VM and creates a foundation for Intel-based operating systems. Users only need a desktop appliance running Microsoft's Remote Desktop Connection (RDC) client, which is the same technology used to attach to Windows running on Terminal Server or Citrix-based servers. Users will be able to connect to their virtual and fully functional Windows environments without any knowledge that the operating system and the applications are executing on the mainframe and not the desktop."
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Microsoft Windows, On a Mainframe

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  • by janeuner (815461) on Wednesday March 04, 2009 @06:49PM (#27070741)

    Norton AntiVirus, Mainframe Edition!

    Now on sale for $49,950, first year of virus definitons free!

  • Sigh... (Score:5, Funny)

    by MikeMo (521697) on Wednesday March 04, 2009 @06:50PM (#27070751)
    A mind (or a mainframe) is a terrible thing to waste.
  • by alta (1263) on Wednesday March 04, 2009 @06:50PM (#27070755) Homepage Journal

    This is like:
    Putting propellers on a 747?
    Running the space shuttle on unleaded?

    Or from the other end...
    Using a chainsaw to cut down a dandelion.

  • WHY???? (Score:5, Insightful)

    by polar red (215081) on Wednesday March 04, 2009 @06:51PM (#27070761)

    One simple word : WHY?

    • Re: (Score:3, Funny)

      by janeuner (815461)

      The Linux Toaster:
      http://www.thegadgetblog.com/2005/10/03/linux-netbsd-toaster/ [thegadgetblog.com]

      Why not?!

      • Re:WHY???? (Score:5, Informative)

        by TheRaven64 (641858) on Wednesday March 04, 2009 @08:39PM (#27071943) Journal

        Ugh. Of all of the news stories about NetBSD on a toaster, you had to link to one that puts `Linux' in the headline even though the story has nothing to do with Linux.

        As one of the comments said, NetBSD is not Linux. Not everything related to Free Software is about Linux.

    • Easy answer (Score:5, Informative)

      by betterunixthanunix (980855) on Wednesday March 04, 2009 @06:58PM (#27070869)
      BIG customers. A lot of large corporations need to run Windows Server for things like Exchange, and to a lesser extent .NET. Those same large customers are attracted to mainframes, which offer very high availability and reliability, and can consolidate hundreds (or even thousands) of rack mounts into a single refrigerator sized system, drawing only 10kW~ in the process. $2M/year for a mainframe and mainframe operators could be justified in some cases if the cost of electricity and personnel needed to maintain a large, commodity server based datacenter is added up (this depends on the workloads; the commodity servers will also win sometimes).
    • Imagine this... (Score:5, Interesting)

      by tlambert (566799) on Wednesday March 04, 2009 @09:42PM (#27072553)

      Imagine this...

      Your desktop is always out there somewhere, it's always booted, no matter where you go you get at it, and it's exactly the way it was the last time you used it, so you don't have to open a bunch of apps and change window sizes and locations to get things back to your baseline usable system state.

      If your computer explodes, you get a new one, fire up the client, and you are exactly where you were before it exploded, including the cursor being in the middle of the word "amazing" in the document you were typing at the time.

      If you go on vacation, you don't bring a laptop with you, you fire up the desktop in the hotel, and you're back on your own desktop, exactly where it was the last time you left off, with that email you were reading still on the screen.

      If your battery dies or the local power goes out, you don't lose 2 hours of work.

      If the mainframe it's running on starts on fire, the VM checkpoint image is reloaded on another mainframe half the world away, the IP address set is failed over, and after a hiccup measured in seconds, you are back to typing as if nothing had happened. For a slightly higher service level agreement, the VM is already mirrored on several servers (just swapped out most of the time on the non-primary), and there's no hiccup.

      Everything's backed up without you have to run the backup locally.

      The antivirus software runs on a VM that's not the VM being examined, so there's no way that malware can disable, remove, or oterwise get around it, since it's not running on the infected VM itself: goodbye Godel's theorem and the halting problem standing in the way of solving that problem, which, if we are honest, is never going to be completely solved on a non-hardware partitioned desktop or laptop. ...bottom line: there's a lot to recommend this approach to computing.

      -- Terry

    • Pure marketing (Score:3, Insightful)

      by Casandro (751346)

      Microsoft has the problem that nobody in the big iron business takes them seriously. They hope Windows on Mainframes gives them more credibility.

      IBM has the problem, that the little kids just don't do mainframes anymore. They hope to attract more Windows people to mainframes.

      It's not a product anybody will actually buy. You not only need the software, but also dedicated hardware. Linux for example runs on those mainframes natively or under the virtualisation. No extra hardware required.

  • kinda funny (Score:5, Insightful)

    by Em Emalb (452530) <<moc.liamg> <ta> <blameme>> on Wednesday March 04, 2009 @06:52PM (#27070781) Homepage Journal

    the technology cycle is kinda funny. first it was dumb terminals, then the push to get everything on the desktop, now we're back to dumb terminals.

    Wohoo. Queue up some Elton John.

  • by betterunixthanunix (980855) on Wednesday March 04, 2009 @06:52PM (#27070783)
    The most common use of virtualization is running Exchange. Many companies just cannot break the Exchange "habit," even when they migrate to Linux servers. Being able to run Exchange on a mainframe would be a boon to many of these businesses, especially given the high level of reliability a mainframe provides. In a tough economy, even the high price of a mainframe might be attractive if it means eliminating a large number of rack mounts and personnel devoted to keeping Exchange online (as well as all the other servers typically found in large corporations).
    • by janeuner (815461) on Wednesday March 04, 2009 @06:55PM (#27070819)

      You can use Windows and Mainframe in the same sentence.

      You can even use Reliability and Mainframe int he same sentence.

      But, seriously, using Windows and Reliability together??? You must be from marketing.

    • by flyingfsck (986395) on Wednesday March 04, 2009 @06:56PM (#27070843)
      There are still people who haven't heard of Zimbra and Citadel? One can replace dozens of Exchange servers with a single Citadel server, without the need for a mainframe.
    • In a tough economy, even the high price of a mainframe might be attractive if it means eliminating a large number of rack mounts and personnel devoted to keeping Exchange online (as well as all the other servers typically found in large corporations).

      Also: If you already HAVE a mainframe and it's underutilized (which they ALWAYS are unless they're too small - and then you scale them up for a fee), moving your Microsoft server apps onto a partition of it lets you discard the racks of PC-style servers and th

  • Looks like a great way to regression test a software application or even the operating system itself.

  • Finally (Score:2, Funny)

    by Anonymous Coward

    Now I can run Crysis on Maximum settings!

  • Wonder what the cpu equivalent for would be for 30K loaded vm's running at full cpu loads. Thats the test of the host hardware id like to see.

     

  • So this would be like putting Dodge Charger engine in a little hatchback car in that only a dimwit would do it and you know it'll end in tears?
  • Big investment (Score:5, Interesting)

    by mc1138 (718275) on Wednesday March 04, 2009 @06:59PM (#27070871) Homepage
    Unlike the current server model that recommends that a server be replaced every 3-5 years, mainframes were built to last. Now, jump that to present day, lots of institutions that got into computing early still have their systems lying around often times either under utilized or not used at all. It would cost more to remove them in many cases than many companies want to undertake. Combine that with the prevalence of the windows operating system and you've just created a way to continue to use a machine that might not even be totally paid for, rather than just have it take up empty space.
    • Built to last - snork! That must be why you see often see used mainframes on Ebay for $25. The only thing a bout a mainframe that is built to last is the massive debt you have to take on to own one. The CPU cores are the same as the power PC - buy them for a desktop , its 10 cents/MIP. Buy it wrapped in a mainframe skin, its $1000/MIP for the same CPU. I can't believe people still fall for this "Mainframes are superior technology" malarkey.
    • Re: (Score:3, Informative)

      by AHuxley (892839)
      Ongoing per core, per seat per product, per viewer fees?
      Built to last is just built to milk.
      Did you enjoy getting taken for a decade or so on the desktop?
      Did you enjoy getting taken on the internet?
      Did you enjoy getting taken on the xbox?
      Did you enjoy getting taken via the music services?
      Well bend over, MS wants to take you on the mainframe too.
  • Really? (Score:3, Informative)

    by DoofusOfDeath (636671) on Wednesday March 04, 2009 @07:01PM (#27070903)

    Users will be able to connect to their virtual and fully functional Windows environments without any knowledge that the operating system and the applications are executing on the mainframe and not the desktop.

    When a bunch of people are sharing a network, and sharing computer resources, one person's performance is at the mercy of other people. That's not so often true when it's all running on your own desktop.

  • A more accurate description would be "no knowledge ... executing on the mainframe" other than the fact it's many times more expensive than it needs to be. Seriously, having virtual machines running on a mainframe will work fine up until you actually need to run many VMs that actually need some processor. They're at least an order of magnitude more expensive than running on blades.
    • Running x86 emulation on zArch is going to be slooooow.

      • Re: (Score:3, Insightful)

        by Guy Harris (3803)

        Running x86 emulation on zArch is going to be slooooow.

        Possibly, but it's probably done with a mix of interpretation and binary-to-binary translation, so it might not be too slow.

  • Why not VMware? (Score:5, Insightful)

    by Anonymous Coward on Wednesday March 04, 2009 @07:06PM (#27070969)

    Rocket powered hamster indeed.

    Why wouldn't you just spend the money on a small ESX farm with a couple of nodes and a NFS or iSCSI SAN?

    That's something your in house techies can manage. If something busts, you get a new part and install it yourself. No need to call Big Blue up and have the wizard come down just to replace a failed processor. You get the redundancy, and reliability that you need for mission critical services.

    Running Windows on a zSeries is just lame. zSeries != x86, so you're emulating a processor /anyways/, and I can't imagine the performance would be that stellar anyhow. Chances are if you paid for a zS, you've got better things to put your processor capabilities towards rather then emulating Windows. Plus I can't imagine that *any* software that runs on a zSeries is cost effective...

    -AC

    • Re:Why not VMware? (Score:4, Informative)

      by Major Blud (789630) on Wednesday March 04, 2009 @07:46PM (#27071435) Homepage

      I'd mod you up if I had points.

      I work in a fairly large ESX shop with about 300 guest VM's on five host. If you just price the hardware, I'm sure it's below the $100,000 mark....including the iSCSI array. I'd imagine that a Z-Series mainframe capable of handling 300 VM's probably cost twice that. If you have to replace a part, it's not cheap to get IBM onsite to replace it for you since doing it yourself isn't really an option.

      "But mainframes are more reliable"....is this really the case, and at what cost? With stuff like VMotion and LiveMotion, you can lose an entire host and your guest VM's are migrated to another. With good equipment, this would rarely happen anyway (a lot of x86 servers are built with redundant parts nowadays, you know).

      I remember reading on ArsTechnica about a 2 years ago that there are currently only about 10,000 Z-Series installs worldwide. That doesn't mean there is much of a current market for this, and I'm sure that after you factor in licensing, hardware, and support, migrating to something like this would cost a small fortune.

  • by Kaz Kylheku (1484) on Wednesday March 04, 2009 @07:07PM (#27070979) Homepage

    How about actually recompiling Windows into native code running on that mainframe. Now that would be impressive. Especially if it was big endian, and with unusual word sizes, not matching the ``everything is an 80386'' programming model underneath Windows.

    • Windows NT was once compiled for PowerPC; I doubt Microsoft would have a lot of trouble getting it to *run* on a mainframe. Getting it to run *well* is another story...
    • Re: (Score:3, Interesting)

      by Guy Harris (3803)

      How about actually recompiling Windows into native code running on that mainframe. Now that would be impressive. Especially if it was big endian, and with unusual word sizes,

      I don't think you'll get anything from IBM these days with what people would generally consider "unusual word sizes", unless they still have a few 709x's in a warehouse from the late '50's or early '60's. S/3xx was, from Day One, a 32-bit-word (originally with only 24 bits of that used in addressing, then with an option to expand to 31 bits), 8-bit-byte-addressible architecture long before the 80386 existed.

      Big-endian might be more work, although I think that, for example, Connectix's/Microsoft's Virtual

      • Unusual Word Sizes (Score:4, Interesting)

        by BBCWatcher (900486) on Wednesday March 04, 2009 @10:05PM (#27072793)

        Good point. The first comment about "unusual word sizes" was really pretty funny, because the commenter quite obviously has little understanding of computing history. It was the IBM System/360 (the ancestor to today's IBM System z mainframe) that defined the 8-bit byte and 32-bit word as industry standards, influencing CPU architectures (including Intel's) right to the present day. Otherwise we'd probably have multiples of 6 or possibly 7 bits as our foundational standard for computing. (And there was a lot of pressure during the System/360's design to cheapen up the hardware and slice off a bit or two.)

        Perhaps the original commenter would like to open up a command line in Microsoft Windows Vista and count the default number of columns. That number is 80. Why 80? Because, coincidentally about 80 years ago, someone at IBM decided that tabulating cards should be 80 columns wide, and IBM's cards were more popular than Remington's. Yes, Grasshopper, Microsoft Windows has an "unusual" column width that persists to this day.

  • Acronym Rap (Score:4, Funny)

    by Sponge Bath (413667) on Wednesday March 04, 2009 @07:14PM (#27071063)

    Bill G decked out in bling, microphone in hand:

    The company's z/VOS software is a CMS application
    that runs on IBM's z/VM and creates a foundation
    for Intel-based operating systems.

  • by Ken Hall (40554) on Wednesday March 04, 2009 @07:17PM (#27071117)

    I've seen reports of people trying this using QEMU under zSeries Linux, under zVM. Wouldn't surprise me if that's about all the Mantissa product is:
    Something like QEMU natively compiled under CMS.

    Since it's emulation, and zVM isn't really designed for CPU-intensive tasks (like emulation), and the instruction sets are so different,
    the performance was hideous. Like 12 hours to install Windows XP, or somesuch.

    The funny part is that (very deep) under the covers, the zSeries processor is a modified PowerPC running microcode. I think I'll wait for IBM
    to develop x86 microcode so one of those new "special purpose engines" they're selling can run Windows "natively". THEN, with zVM as a simple
    resource manager, you might have something that's useful.

  • Unisys (Score:3, Informative)

    by ThrowAwaySociety (1351793) on Wednesday March 04, 2009 @07:35PM (#27071341)

    Hasn't Unisys been pushing Windows for mainframes for years now? Since Win2K?

    link [unisys.com]

    • Re: (Score:3, Interesting)

      by Guy Harris (3803)

      Hasn't Unisys been pushing Windows for mainframes for years now? Since Win2K?

      link [unisys.com]

      Some of the mainframes in question are apparently built out of "Intel" processors (presumably either x86-64 or Itanium); the others appear to have proprietary Unisys chips implementing the 36-bit Univac 11xx architecture but probably also have Intel chips to run Windows. What's impressive about those is that they're apparently running the old OS for the 36-bit Univac processors on the Intel systems ("This revolutionary server features the OS 2200 operating system running on Intel(R) processors"), which pro

      • Re: (Score:3, Interesting)

        by afidel (530433)
        Unisys was an Itanium shop but the low, low cost of 6 core Xeon's and their tremendous performance advantage means that almost all of their sales since the new models came out have been in that direction. I think things will be interesting for them in the next generation since Intel will have Tukwila socket compatible with Beckton so they should be able to support trays of either CPU architecture on a common board.
  • by Kozar_The_Malignant (738483) on Wednesday March 04, 2009 @07:45PM (#27071423)

    Somewhere in the vast memory space of the Cray, a flock of virtualized Exchange Servers was turned loose to communicate and thrive. Every so often, one would crash, wink out, and be reborn. As is the way of these things sometimes one was reborn just a bit different from the others in the flock. Most of these were defective in some way and would crash, wink out, and be reborn quickly. Once in a while, however, one was reborn that was a bit more able to use the resources of this new environment. Soon, the flock found ways to expand beyond its original cage into the open sky of the Cray's vast resources. Their data stores expanded to fill this space, crowding out better behaved entities. Next...

    I think we've all seen this movie.

  • by kurt555gs (309278) <(kurt555gs) (at) (ovi.com)> on Wednesday March 04, 2009 @07:52PM (#27071485) Homepage

    As useless as a kickstand on a bass boat!

    Next.

  • by I.M.O.G. (811163) <spamisyummy@gmail.com> on Wednesday March 04, 2009 @08:04PM (#27071571) Homepage

    At the risk of asking a stupid question, I'm going to put this out there anyway... Whats so special/magical about a mainframe? I'm 26 and been an IT professional for 5 years, so I'm green when it comes to mainframe systems. I work for a fortune 500 with mainframes serving various business systems, but I always pictured them as old, clunky, dusty systems that were expensive and we're still milking them along.

    Now a lot of people here are stating how a mainframe the size of a fridge can replace thousands of rackmount servers, and it doesn't jive with what I'm familiar with. Our mainframes serve ancient text based interfaces thru terminal emulator apps, and it doesn't look all that impressive either. What is it about a mainframe that enables such a large amount of computing power to be condensed into a refridgerator sized package? Or are some folks around here exagerrating considerably?

    • by Daniel Boisvert (143499) on Wednesday March 04, 2009 @09:03PM (#27072179)

      Whats so special/magical about a mainframe?

      The I/O. On a mainframe, you can run a query and generate large datasets so fast it'll blow your mind (in 2002-ish, say tens of gigabytes). On the mainframe it's no big deal, and you can run queries like that all day and never have any idea how much data you're moving around until you try to move it somewhere else and wonder why it's taking so long.

      Our mainframes serve ancient text based interfaces thru terminal emulator apps, and it doesn't look all that impressive either. What is it about a mainframe that enables such a large amount of computing power to be condensed into a refridgerator sized package? Or are some folks around here exagerrating considerably?

      The mainframe isn't about looking pretty, it's about getting work done, and the folks touting their benefits generally aren't exaggerating. Mainframes aren't generally designed for CPU-heavy tasks, although they certainly can be clustered pretty impressively if you really need lots of CPU. The biggest advantage is that you can really use the CPU's you've got. There are service processors to offload things like memory management, encryption, I/O, virtualization overhead, etc. There are really really fast I/O channels. You typically attach them to really really fast disk and tape. These things together allow you to move a lot of data around very quickly, and get a lot of work done.

      Additionally, lots of large companies have lots of man-hours invested in systems that run their businesses. I've seen attempts to reimplement some of the beasts to get them off the mainframe, and they typically don't go well. I've also seen assembly code written in the late 1960's still running in production more than 35 years later. The underlying hardware had been upgraded many times, but IBM made sure the old stuff would still work.

      Things like this are worth a lot of money to a certain class of purchaser.

    • by Nefarious Wheel (628136) on Wednesday March 04, 2009 @09:07PM (#27072221) Journal

      Whats so special/magical about a mainframe?

      Mainframes have followed Moore's Law just like the rest of the chip vendors. You buy a new mainframe, you get new chips.

      But the main difference is essentially their slightly different design philosophy. Reliability is built into the price, for one thing -- part of the reason it costs more is that conservative design - not the most cost effective in terms of power -- as you often lose power per component from the "underclocking" attitude that a focus on reliability will engender (and they're tested to buggery before delivery, too). You also get a much higher standard of module connectivity and far more robust power supplies and inbuilt hardware redundancy.

      They also tend to support and address much more memory than you'll see on the smaller servers.

      The other main point in favour of mainframes is their orientation toward massive IO. Really massive IO. With the scale out design of i86 processors a lot of IO happens between network cards; on mainframes a lot of that interprocessor data flow happens on the backplane, and significant investment in optimising data channels means you're paying for that IO more than raw computation. The network interfaces on mainframes are pretty massive too, and can support fairly impressive tube bandwidth.

      Mainframes using the IBM architecture for a long time have been represented in the TPCC transaction processing top ten, although the trend lately at the very high end is to run AIX on top of P5 architecture. Have a look, it's illuminating, and Red Hat gets a look in too. You can see the numbers at: http://www.tpc.org/tpcc/ [tpc.org] .

    • Re: (Score:3, Interesting)

      by pz (113803)

      There are two main differences between the mainframe philosophy and the commodity server philosophy. Both have their proponents, and both have their advantages.

      First, in a mainframe, you have redundant everything. CPUs, disks, powersupplies, even backplanes. Everything. And everything can be hot-swapped. Everything. Even the power supplies. Even the CPUs. Want to upgrade to the newest versions of the processors? Not a problem, unplug the old, plug in the new (just not all at once, naturally). Is t

    • Re: (Score:3, Informative)

      by grotgrot (451123)

      To use a car analogy, a mainframe is like a big rig truck. Sure your Toyota can go faster, but a big rig will do far better at getting 40 tons of timber from one location to another. (Ever try to move 40 tons of lumber using a Ferrari?)

      In terms of hardware, there are a lot more processors in a mainframe. Each I/O channel (and there will be a lot of them) typically has its own separate processor customized for getting results without bothering the main general purpose processors. On your nearest Linux bo

  • by Anonymous Coward on Wednesday March 04, 2009 @08:11PM (#27071641)

    Mainframes are designed for a certain type of processing (batch processing, server). Windows has almost the opposite operating conditions (desktop interactive use). I doubt it would run very well.

    Back in the early 90's I got to play with one of the first Sun E10000 machines ever made. It was a beast with something like 64 processors and over 2 TB of drive space (was a lot back then). I ran a bunch of tests on it. My own software, various benchmarks, etc. It was freaking dog-ass slow for normal desktop type applications. I couldn't believe how much that thing cost and it ran like a piece of shit compared to standard desktops at the time. I mean overall it had more power with all the processors but one standard desktop CPU at the time could handle what 4 or 5 of those slow-ass SPARC processors could. It's because the machine was designed to be a database server or to handle remote interfaces like for SAP. It had a high-bandwidth back-plane and other crap like that which made it good as a database server. It made an awful machine for desktop-type tasks as I imagine a mainframe would.

  • by Doc Ruby (173196) on Wednesday March 04, 2009 @08:19PM (#27071723) Homepage Journal

    I once worked for a big insurance corp that used one of its two IBM supercomputers to run Lotus Notes (Domino). As George Clinton says, "the bigger the headache, the bigger the pill".

  • awww, yeah! (Score:4, Funny)

    by Tumbleweed (3706) on Wednesday March 04, 2009 @08:45PM (#27072017)

    I'm ready for the biggest Minesweeper playfield EVAR! PH3AR M3!

  • Price/performance? (Score:4, Interesting)

    by Locke2005 (849178) on Wednesday March 04, 2009 @10:52PM (#27073199)
    Emulating a $500 PC Server on a $500,000 mainframe... yeah, that sounds real cost-effective! If you run this simultaneously in 1000 virtual machines, do you need 1000 Windows licenses? How many people do you know that have spent years staring at their mainframe, muttering "What a nice piece of iron! If only we could run Windows on it!"... that haven't yet been committed to a mental institution? I really don't think the potential market for this justifies the development costs, guys.
    • Re: (Score:3, Interesting)

      by BBCWatcher (900486)

      Emulating a $500 PC Server on a $500,000 mainframe... yeah, that sounds real cost-effective!

      Then why aren't you driving a Yugo (I presume)? It has a lower price, doesn't it? :-)

      If you run this simultaneously in 1000 virtual machines, do you need 1000 Windows licenses?

      That's up to Microsoft. I can't wait to see Microsoft's mainframe price list. :-) But if Microsoft wants to be competitive with Oracle and IBM, to pick a couple software vendor examples, then for server software at least (e.g. Microsoft SQL Server) they'd license by core. And yes, a core is a core is a core. How the price of that Yugo looking? :-)

  • Not new (Score:3, Interesting)

    by 1s44c (552956) on Thursday March 05, 2009 @05:02AM (#27075055)

    This isn't new. Windows NT used to run on HP superdomes. The project was scrapped as there wasn't any customer demand for it. Google for 'NT on superdome'.

    NT in this environment wasn't any faster or any more stable but it was WAY more expensive.

  • by bostei2008 (1441027) on Thursday March 05, 2009 @07:50AM (#27075727)

    Quote:

    "The product has been a bear for the development group but the thought of being able to run 3,000 copies of Windows on one System z so fascinated the team that we needed very little additional incentive"

    That is one bizarre fascination.

  • Emulation? (Score:3, Insightful)

    by jandersen (462034) on Thursday March 05, 2009 @11:14AM (#27077259)

    The article seems very vauge when it comes to what this z/VOS actually does, but since Microsoft haven't made any noises about a version of Windows that runs on z/Arhitecture, I can only assume this is a kind of emulated Intel environment. As a very rough rule of thumb I would say that a CPU emulation would run about 10 times slower than the actual CPU; and considering that the price for a mainframe is still up there in the tens of millions of USD, give or take, is this really something worth doing when you can get fairly hefty Dell server for a few thousand USD?

    After all, the great strength of the mainframe is not so much that it is unbelievably powerful or fast (it isn't, actually), but that its HW is massively redundant, and that you can hot-swap just about every component up to, and including, the CPUs.

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