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The Pros and Cons of Mainframe Linux

magellan writes "There is a good article on LinuxWorld.com that goes over some of the pros and cons of Linux on the mainframe. The author, Paul Murphy is an old mainframer and current UNIX user, as well as a frequent contributor to LinuxWorld.com, so he has some good insights. "

233 comments

  1. Gotta be better than M$ Windows Datacenter. by tmcmsail · · Score: 3, Funny

    Linux the utility OS, runs anywhere. I have it on Intel & Alpha at home. What hardware do you want to make sing today :-)

    --

    What OS do you want to abuse today?

    1. Re:Gotta be better than M$ Windows Datacenter. by Anonymous Coward · · Score: 0

      Vax...

      Before someone else gets to it, I'm aware of this:
      http://linux-vax.sourceforge.net/

      Wouldn't really call that singing though...

    2. Re:Gotta be better than M$ Windows Datacenter. by tmcmsail · · Score: 1

      So many Anonymous Coward's. A site that wants you to be "comfortable with the command line," Gosh, I should be scared, I haven't seen a command line in about 5 minutes..

      and a site that is so current, too:
      "Last modified Wednesday, September 19, 2001 11:53:39"

      A friend once saw a blue screen in NT and said "Ah Windows running in it's natural state."

      --

      What OS do you want to abuse today?

    3. Re:Gotta be better than M$ Windows Datacenter. by Anonymous Coward · · Score: 0

      NetBSD runs Multi-Processor on old vaxen, I think the processors i saw it running on were clocked at 3 or 5 IPS(instructions per second). Now that's singing, albeit slowly!

    4. Re:Gotta be better than M$ Windows Datacenter. by Anonymous Coward · · Score: 0

      It ain't over till the fat lady sings, and Linux is the biggest piece of bloated shit I have ever laid eyes on. I used to run Linux until two days ago, when I found BeOS. Browsing through BeBits I realized all those applications I use under Linux had attractive and faster alternatives for a real OS, so I thought "Heh! Time to give this one a shot, I migrated to Linux.. why not BeOS? Everybody seems to like it". Guess what? Even on a 200mhz it is 6-8x faster than Windows 9x, and guess also what? Linux is 6-8x slower than Windows 9x. You know, maybe it's not fair for me to criticize Linux as a whole, but what I really can't stand is the shitty bloated design of XF.

      Thanks. This was not an auto-generated troll, lol. I just saw this queer talk about how Linux "sings" and had to say: BeOS sings. Linux mutters miserably and sputters.

      :>.

    5. Re:Gotta be better than M$ Windows Datacenter. by Anonymous Coward · · Score: 0

      It is obvious that you are a man of great experience. I bet that you are even a teenager. I can not wait untill I am as old and mature as you.

  2. Linux has scalibility problems by atrowe · · Score: 1, Interesting

    I work in a large datacenter with some very powerful machines, and I just don't see Linux having much of a future on mainframes, at least not without some serious kernel improvements. It is an excellent OS, and would be a good choice for a workstation or a low-end server, but would be a very poor choice for a high-end mainframe machine. The linux kernel is highly configurable and it would certainly be possible to get a Linux kernel running on a massively parallel machine, but this was not what Linux was designed for, and performance would not be on par with other more robust Unices. Linux' inferior TCP/IP stack as well as its inferior handling of multi-threading on a large scale is its major weakness in this area. Until these weaknesses are addressed, I would prefer Solaris, Irix, or HP/UX instead, as they were designed from the ground up with mainframe usage in mind.

    --

    -atrowe: Card-carrying Mensa member. I have no toleranse for stupidity.

    1. Re:Linux has scalibility problems by Anonymous Coward · · Score: 1, Informative

      I couldn't agree with you more. My company gave the Linux-on-a-mainframe idea a trial run, and I'm sad to say, it just couldn't keep up with the load we were running through it. Both the VM and the scheduler were serious limitations compared to the Unices we have in use.

    2. Re:Linux has scalibility problems by micromoog · · Score: 3, Funny
      Your sig:

      -atrowe: Card-carrying Mensa member. I have no toleranse for stupidity.

      "tolerance"? . . . oh, the irony.

    3. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0
      You're absolutely right ...

      On a "raw iron" basis, the zSeries beats high-end PC servers. The zSeries doesn't stack up against mid-range Sun gear, and, by extension, against competing PA-RISC and Alpha products.

      On a workload applicability basis, the zSeries fits Linux about as well as snowshoes go on a downhill ski racer.

      For an easily severable workload, like Domino, the same benchmark results that show a 10-way mainframe getting a NotesMark score of 42,508 suggests a cluster of five Dell 2450 PC servers for a total of around $61,000 would blow it away on both absolute and relative performance.

      We don't have a comparative performance benchmark for a mixed workload of relatively small, but unpredictable tasks of the kind Linux on x86 excels at. What we do have, however, is comparative cost information on the basic systems. At list price, you could create a rack of 80 Dell 8450 servers, each sporting:

      Four 900-MHz Xeon processors each with 2 megabytes of cache
      16 gigabytes of RAM
      4 x 73 gigabytes US3 disk
      Red Hat Linux pre-loaded
      for about the same money as one fully configured z900.

      Today, Linux doesn't scale well past four processors and about 4 gigabytes of RAM, but other Unix variants do. If your workload needs massive SMP capabilities with flat memory spaces above 16 gigabytes the place to start is with the Sun 3800 at about $200,000 fully configured, but the only direct comparison for which we have performance indicators is with the larger 6800:



      Apparently, IBM can not compete with Dell. There you have it folks, IBM is dying.

      --
      post early , post often.
    4. Re:Linux has scalibility problems by JanneM · · Score: 2

      Of course, the use for Linux on a mainframe _is_ as a low- to medium server, running virtually atop VM. I have not sen anybody seriously advocate running Linux as the base OS on such a machine.

      /Janne

      --
      Trust the Computer. The Computer is your friend.
    5. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      not irony, more like, YHBT by atrowe...a trowe...a troll...HAND!

    6. Re:Linux has scalibility problems by Pauly · · Score: 2, Insightful
      And I just thought he was an idiot for stating that Solaris, Irix, and HP/UX "were designed from the ground up with mainframe usage in mind".

      UNIX was designed to get away from the mainframe usage paradigm, not reinforce it. Read the article. It yields good insight into the differences between the Mainframe Way (machine resources are more important than user demands) and the UNIX Way (users needs are more important than the machine's).

    7. Re:Linux has scalibility problems by the_2nd_coming · · Score: 1

      Linux will get there very soon. with the new test kernel, they have added the preemtive patch which increases the ability for the OS to process transactions. also, the preemptability will increase as the SMP ability increases as the preemtion is ties to the SMP locks. as the SMP locks get more and more finegrained, the preemtion points become more and more fingrained. you now have the potential for masive scalability.

      --



      I am the Alpha and the Omega-3
    8. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      I thought that Unix was created to move away from non-portable assembly to a way that could create a highly portable language with the speed of assembly.

      Unix was an OS that was created to be highly portable......I think Stalman even used a version on a PDP-11

    9. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Not to mention Mensa is just a bunch of elitist assholes just sitting around patting eachother on the back.

      This belief in a general intelligence is ridiculous. Even if it existed, what good would it be?

      The only intelligence with any meaning is one's intelligence in a particular field of knowledge. If you are smart at computer programming that impresses me. If you are a smart at auto-mechanics that impresses me. But if you think you are just plain smart, you are probably fooling yourself. I may be good at programming, but compared to my auto-mechanic I'm an idiot if what we're talking about cars. Intelligence is always relative.

      Furthermore if you have actual skill in a particular field of knowledge, the way you demonstrate it is by doing good work in that field. Not by getting together with a bunch of other people who also think they are smart and sucking eachother's dicks.

    10. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      But if you think you are just plain smart, you are probably fooling yourself. I may be good at programming, but compared to my auto-mechanic I'm an idiot if what we're talking about cars. Intelligence is always relative.

      maybe you're just a dumbass. i conside myself pretty smart in all areas, you know why, because i am working on a phd in math. everything else seems trivial, and it is.

    11. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Not to mention Mensa is just a bunch of elitist assholes just sitting around patting eachother on the back.

      Sweet, just like Kuro5hin? I fucking hate those elitist retards...oh, I'm sorry, "intellectualists."

    12. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0
      i conside myself pretty smart in all areas, you know why, because i am working on a phd in math


      Sorry, you just disqualified yourself! Thanks for playing.

    13. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Oh wait! I majored in everything! Now you are shot down!

      btw that was such a good argument. You really got me there.

      I doubt you even have a degree.

    14. Re:Linux has scalibility problems by echo · · Score: 0, Troll

      The problem with zseries mainframes is that they are VERY low powered CPU wise to start with. It's not really Linux's fault.

    15. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Does your mom's basement get cold at night?

    16. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Oh gee! You're killing me. I guess that would hurt more (a) if my mom had a basement and (b) if I didn't live in a house I own.

      But if you must recourse to juvenile insults: I can say that your mom's bed doesn't get cold at night. Of course you already know that.

    17. Re:Linux has scalibility problems by Mr.Sharpy · · Score: 1

      To me, true intelligence is the ability to draw on the knowledge that you already possess to synthesize new ideas and concepts. It is the ability to think, REALLY think, that is important. That's the source of common sense, which sadly is lacking in most people these days.

      That's why schools in the US are so abysmal. They have gone the route of trying to shovel in dry facts and data into the empty heads of the young rather than teaching them how to think. It's like mental welfare.

    18. Re:Linux has scalibility problems by Washizu · · Score: 1

      He's being sarcastic.

      --
      OddManIn: A Game of guns and game theory.
    19. Re:Linux has scalibility problems by Inoshiro · · Score: 2

      "Linux' inferior TCP/IP stack"

      Zero copy networking not good enough for you? You want networking that somehow zips packets along without even touching them except by telepathy?

      Back under your bridge, troll.

      --
      --
      Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
    20. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Shouldn't you be outside enjoying the nice afternoon? Your mom is gonna make you go inside and work on your homework soon.

    21. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      You call the joke that is sendfile zero copy networking? Sure thing, kid.

    22. Re:Linux has scalibility problems by mrm677 · · Score: 4, Informative

      You are incorrectly aggregating mainframes, shared-memory multiprocessors (SMP/NUMAs), and clusters as massively parallel machines.

      Linux makes a great operating system for certains classes of massively parallel machines: clusters. It is low-cost and has a decent MPI (message-passing interface) implementation. It also runs on commodity hardware. Don't be surprised if you see the next ASCI supercomputer using Linux as the OS for each node.

      You are correct in that Linux is not a good operating system for larger shared-memory multiprocessors. It lacks the fine-grained locking necessary to run the same kernel instance across dozens of processors.

      I can't comment on mainframes because I am unaware of their architecture. I do know that high-end UNIX servers and mainframes are different beasts. The former focus on performance while the latter prefers uptime above all. I also believe that IBM, the kind of mainframes, has not used UNIX as their traditional operating system. Thus you are comparing apples to oranges. Linux makes a perfectly decent "mainframe OS" if you are partitioning the machine into multiple virtual machines.

      Also please elaborate on "Linux' inferior TCP/IP stack". And "inferior handling of multi-threading on a large scale". Are Solaris light-weight processes any better?

    23. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Sorry I can't understand you. Maybe you'd speak more clearly if you took your dad's dick out of your mouth.

    24. Re:Linux has scalibility problems by BadTuna · · Score: 2, Funny

      Gee! Someone used Linux and inferior in the same sentence ! Don't you know you will be banned from /. for eternity?

      --
      Your sig here!
    25. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Just so you know, atrowe is a known... well... it sounds kind of like "atrowe"...

    26. Re:Linux has scalibility problems by Shabazz · · Score: 1

      Pity the fool who moderated this up. The sig, while not funny, is clearly meant to be a joke. There are thousands of pathetic sigs like it throughout slashtopia. I think it all is based on the Far Side Comic with the caption "Midvale School of Gifted" where the door says push and the mentle giant is pulling for the life of him and can't get in.

    27. Re:Linux has scalibility problems by dustym · · Score: 1

      It is Midvale School for the Gifted, and the guy is pushing when the door says "pull".

      Thanks,
      dustym

    28. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      You obviously fail to understand how a mainframe works. A mainframe is VERY powerful, yes, but that computing power is divided into PARTITIONS (the whole concept of a VM). So those 16 processors you have in a mainframe aren't all running a single kernel, rather, z/VM runs on that and puts up the appearance of virtual machines, which are smaller, more managable boxes.

    29. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      anal Pronunciation Key (nl)
      adj.
      Of, relating to, or near the anus.
      Psychology.
      Of or relating to the second stage of psychosexual development in psychoanalytic theory, roughly from ages one to three, during which gratification is derived from sensations associated with the anus and defecation. The anal stage is preceded by the oral stage and followed by the phallic stage.
      Indicating personality traits that originated during toilet training and are distinguished as anal-expulsive or anal-retentive.
      Of, or pertaining to the user "dustym" on slashdot.

    30. Re:Linux has scalibility problems by Pig+Hogger · · Score: 2
      ...
      I just don't see Linux having much of a future on mainframes, at least not without some serious kernel improvements.
      Perhaps you don't see the idea. Linux is DEFINITELY NOT an operating system for the whole mainframe (that's VM's job), but merely an operating system for the application alone.
    31. Re:Linux has scalibility problems by Tony-A · · Score: 2

      Early mainframes were expensive. CPU time metered and charged by the second. Only large corporations or government could afford them. Second generation mainframes topped out at essentially 64k bytes (7074 had 10,000 10-digit decimal words storage).
      Solaris, Irix, and HP/UX were designed as big UNIX, (which is something rather different from small mainframe). Each probably based on Berkely UNIX and each trying to distinguish itself as something special. The big UNIX did encroach on the mainframes turf, often doing more, better and cheaper.

    32. Re:Linux has scalibility problems by Gsus411 · · Score: 1

      I disagree. The schools these days don't just shovel in the facts. I know, I'm a freshman in high school. We really don't need to learn anything, as long as we can make art about the subject. In my history class, our final project is to make something that looks like a WWII propaganda poster. Our notebooks are graded on their visual appearence, not their written content. Spanish is even worse. We are supposed to write a short story in Spanish, then make a short picture book about it, without the actual Spanish text. Keep in mind that I take all honors and AP classes. The only class I actually learned anything in was computer programming and geometry. Those classes hammered in the facts, and left it up to us to apply them.

    33. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      There's nothing wrong with being gay. I think most people would agree there is something wrong with sucking off your dad, which is what you just admitted to. Since I don't even know your dad, I guess only the half about you "clean[ing] it off" can be true.

    34. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      No I think you full of FUD. Linux scales very well have you read about Beowulf. With Linux you are going to have to hack the kernel and write a module or device driver or two if your configuration is not supported but thats not a problem because you have the source code so use it. Big Iron Unix Sucks it can only do one thing but Linux can scale from a wristwatch to the mainframe. But yes in order to run on these different platforms you are going to have to tweak the Penguin. The problem is not with Linux being ready for the mainframe the problem is with your approach to using Linux on the Mainframe. If you have those Microsoft Certified Nuts then just do not listen to their crap and by the way they are probably to busy rebooting another BSOD or playing HEARTs to be too much a bother to you. Go to your boss and show him or her how Linux can scale the Mainframe. Linux can Scale the Mainframe and it already has and is running on lots of Supercomputers such as NOAA you do trust your weather report well its the Penguin that is crunching that data for NOAA.

    35. Re:Linux has scalibility problems by jo42 · · Score: 1
      The Linux kernel needs more than a 'patch' - it needs a rewrite from ground up to get past where it is stuck now.

      Linux Bad, FreeBSD Good.

    36. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      The point about the IP stack is that Linux's
      isn't multithreaded to pass multiple packets
      at the same time. The Samba development team
      commented on this, saying specifically that
      it impeded performance, compared to stacks like
      the one in Solaris.

    37. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      What the fuck are you doing in your "datacenter"? Linux clusters do massiave particle, nuclear, and weather simulations. Do you think that it is not possible to do your fucking payroll, mrp, scheduling, or whatever the fuck you do.

    38. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Unix was made to be an interactive system. The user has always been the center of the unix universe. Just like windows was not designed to support multiple users, unix was not designed to support batch procesing---which is why we do not see any batch processing kernels.

    39. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      Yes, I am sure that you are very smart. Now the challenge is to apply that to something. A person who can apply lesser brain-power is a much better man than a prick who just congratulates himself for getting a degree.

    40. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      I reproduce more than you. I win!

    41. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      I took AP math and history, but general english (yea I know, but I can't fucking spell), and I can assure you that the problem is that you are in AP classes. They try to make artists out of us. In general english, we concentrate on the fundamentals, a paper is graded on the spelling, language, and content not on my ability to use a consistent metaphor, or repitition, or sylible rythim. God forbid if you are a good technical writer, it would go unrecognized, they want the fucking declaration of independence.

    42. Re:Linux has scalibility problems by Anonymous Coward · · Score: 0

      You should see some of thoes "patches"; they are mostly rewrites.

  3. Re:Linux Sucks! by yiffyfox · · Score: 1, Offtopic

    It's open source, if you don't like it fix it.

  4. I throw rocks at retarded kids by Anonymous Coward · · Score: 0

    I don't get it, why would you want to run Linux on a mainframe? There are serious issues that leave Linux with limited scalability, even if you're running a few dozen virtual machines. It just seems like a waste with all the effort that's already been put into a truly fantastic machine and OS.

  5. Doesn't solve anything.... by qurob · · Score: 1, Troll

    It's still Linux, whether you run it on a Celeron or a mainframe.

    You've got the right hardware, but the software still isn't 'mainframe' level.

  6. Thanks for the article... by swagr · · Score: 4, Funny

    I was about to spend 5 million dollars on a new zSeries setup, but after reading the article I thought "maybe my laptop is good enough for now".

    --

    -... --- .-. . -.. ..--..
    1. Re:Thanks for the article... by Anonymous Coward · · Score: 0

      Funny??

      Feel the sting of my METAMOD!!!

  7. Confused author? by FyRE666 · · Score: 1


    (see this report of a test on a 733-MHz Linux system for details on mstone) run on the mainframe.

    Yes, it's a word document. You'd think anyone writing an article for a Linux targetted site would at least check or convert the document to something everyone can read...

    1. Re:Confused author? by Anonymous Coward · · Score: 0

      I hate to break it to you, but some people can't read. They should have converted it to pictures

    2. Re:Confused author? by Anonymous Coward · · Score: 0
  8. Is not better than solaris by superpulpsicle · · Score: 2, Interesting

    Besides pricing, the more high end the server goes... the more I will lean toward solaris.

    I am linux-biased folks are going to / me for this.... but I am speaking from experience.

    1. Re:Is not better than solaris by Anonymous Coward · · Score: 0

      People who understand English grammar disagree. Care to expand on your high-end linux "experience"? How many simultaneous Linux instances have you run on YOUR mainframe? Over 900? No? Then you are talking out of your ass.

    2. Re:Is not better than solaris by Analog+Squirrel · · Score: 0, Flamebait
      Burn the infidel! burn !!!!!!!

      :-)

      --
      I'd rather be flying
    3. Re:Is not better than solaris by Anonymous Coward · · Score: 0

      Yes, I am sure that you run 900 instances on your mainframe, but I could get 900 pentium 233's for $100,000, and kick the shit out of your mainframe's performance.

  9. This is about MAINFRAMES not minis by Ashurbanipal · · Score: 2, Insightful


    Um, Solaris, Irix, and HP/UX (shudder) are *NOT* mainframe operating systems.

    MVS and OS/390 are mainframe operating systems.

    You are talking out of your nether regions, especially when you call linux's TCP/IP stack inferior to HP/UX. I have adminned every operating system mentioned above except Irix, and you sir are grossly incorrect.

    1. Re:This is about MAINFRAMES not minis by Anonymous Coward · · Score: 0

      No, he's correct. Feel free to supply evidence if you disagree.

    2. Re:This is about MAINFRAMES not minis by Ashurbanipal · · Score: 1

      Naah, I've been trolled enough on this topic, I need to go have this hook removed from my lip.

    3. Re:This is about MAINFRAMES not minis by jo42 · · Score: 1
      > Um, Solaris, Irix, and HP/UX (shudder) are *NOT* mainframe operating systems.

      Damn! You are right... Irix runs on 128-, 256-, 512- and 1024- processor machines, potentially with terabytes of RAM. It is a supercomputer OS, not a mere lowly mainframe OS.

      Linux Bad, FreeBSD Good.

    4. Re:This is about MAINFRAMES not minis by Anonymous Coward · · Score: 0

      Irix my run on big boxes (more like rooms), but it is not the same Irix that you run on your little Indy.

  10. Re:finally by Anonymous Coward · · Score: 0

    noooooo.....nu-uh....you can't use NT on a mainframe.

  11. Re:finally by Anonymous Coward · · Score: 0

    You would think that.

  12. Re:Linux Sucks! by Anonymous Coward · · Score: 0

    It's open source, if you don't like it fix it.

    Is it an obligation? Or can I just use something else?

  13. Re:correction by apt-get · · Score: 0, Redundant

    GNU stands for "Gnu's not Unix."

  14. Report roasts Linux by Smackmaster · · Score: 4, Interesting

    Funnily enough I just came across this article on ZDNet that talks about how Linux isn't a very good long term server solution. Its here at http://zdnet.com.com/2100-1104-909084.html

    1. Re:Report roasts Linux by spudnic · · Score: 2

      Your message is a bit misleading. The full title of the linked article is "Report roasts Linux on mainframes" It doesn't say that Linux isn't a very good long term server solution, it says that Linux on the -mainframe- may not be a good long term solution.

      .

      --
      load "linux",8,1
    2. Re:Report roasts Linux by Anonymous Coward · · Score: 0
      Moderators, are you stupid? 'zdnet.com.com'

      Its's a TROLL !!!

    3. Re:Report roasts Linux by Simon+Brooke · · Score: 5, Informative
      Funnily enough I just came across this article on ZDNet [zdnet.com] that talks about how Linux isn't a very good long term server solution

      Yes, but note firstly that this article is making two different points, and secondly that at least one of them is clearly wrong and deliberatly misleading.

      First the article claims that Linux on mainframes isn't price efficient compared to Linux on Intel, and that Intel boxes are emerging which have similar reliability to mainframes.

      Possibly true; I don't know enough about mainframes to know, although I'm certainly not aware of these high-reliability Intel boxes.

      Second, the article launches an ill-informed FUD assault on Linux, saying

      • 'Linux vendors for requiring users to constantly update their software to fix errors'
      • 'current Linux incarnations are relatively immature, as evidenced by the interminable list of errors/patches on Linux providers' Web sites'
      • 'Linux isn't capable of running more complex, critical applications, such as e-mail notification systems'
      Are any of those things true? What does that say about the rest of the article?
      --
      I'm old enough to remember when discussions on Slashdot were well informed.
    4. Re:Report roasts Linux by Anonymous Coward · · Score: 0

      Nice try. Com.com is owned by ZDNET. zdnet.com.com resolves to the same page as zdnet.com.

      No troll, but nice try to label it as such...

    5. Re:Report roasts Linux by fferreres · · Score: 2
      Save your time, according to this articule, Linux in the mainframe will fail because:


      "The company says that, at least for the moment, Linux isn't capable of running more complex, critical applications, such as e-mail notification systems."

      Intel-based servers are emerging with mainframe-like capabilities


      Geezz...

      --
      unfinished: (adj.)
    6. Re:Report roasts Linux by Anonymous Coward · · Score: 0

      The report is true. Linux is really not very good. Check out FreeBSD if you want a good Unix(tm) operating system that runs on your PC
      that's really free source.

  15. Re:finally by crow · · Score: 5, Informative

    Linux was never ported to the 486 and Pentium. As they support the same instruction set as the 386, no porting was necessary. Sure, over time enhancements were made to take advantage of specific features of various x86 features, but that's not porting.

    And GNU has nothing to do with porting of Linux to any platform.

    And your corporate mainframe doesn't run NT. Or if it does, you're using a definition of "mainframe" with which I was not previously familiar.

    And preemptive multithreading and protected process management is not new to 2.4.5. That's something that has been in every Unix since, oh, about 1970. It's also something that has been in every enterprise-class system in the past twenty years. I would hardly call it a boon to admins.

  16. You are NOT talking about MAINFRAMES by Ashurbanipal · · Score: 5, Informative

    AFAIK, there are no mainframes that run NT. And I've never seen one with a USB port, either. Your post makes absolutely no sense from a mainframe perspective. What are you talking about with "dual boot"? Mainframes can run multiple simultaneous LPARs, which are virtual machines sort of like VMware provides, but nobody ever boots a mainframe if they can avoid it. And mainframers don't use the word "boot" anyway, since individual components of the mainframe can be individual restarted. Mainframers IPL from the HMC, which is the analogous operation to rebooting. Mainframes run VM, MVS, OS/390, and similar. They don't run NT or OpenBSD (though OpenBSD could probably be ported). There is no graphics console device on a mainframe, so how the hell could you run NT?

    1. Re:You are NOT talking about MAINFRAMES by finkployd · · Score: 2

      You got most of the terms right so I assume you know what you are talking about. I just wanted to point out that Multiprize 3000 (a really low end s/390) has USB ports...and a sound card. Strange really :)

      Finkployd

    2. Re:You are NOT talking about MAINFRAMES by red_dragon · · Score: 1, Redundant
      Multiprize [sic] 3000 (a really low end s/390) has USB ports...and a sound card.

      Sure, but where can I plug in my 1337 GeForce 4 Ti video card? And how many FPS am I gonna get in UT?

      ... had to ask.

      --
      In Soviet Russia, Jesus asks: "What Would You Do?"
    3. Re:You are NOT talking about MAINFRAMES by bluehand · · Score: 1

      Nops The MP3000 doe not have USB the SBC (single board computer) that have the usb and sound card i known its strange, but you have 2 computers inside the MP3k , one is the sbc the other is the Mainframe the sbc is the Processor Console, it runs OS/2 and a software that controls the Mainframe (Stuff like defining channels, IODF, Loading Microcode, IPL and the Stuff) the Mainframe and Mainframe OSes in general dont suport USB, they dont even suport CD roms or Video Cards (For the Mainframers out there, I know Theres GD but its not a video card like people know today and nobody in IBM Brazil has ever seen one so it account for its use :) ) plese people try to learn more about the machines before you start talking

    4. Re:You are NOT talking about MAINFRAMES by finkployd · · Score: 1

      Oh, ok thanks.

  17. Re:finally by Anonymous Coward · · Score: 0
    Sorry, I am still getting over choosing a Mainframe operating system based upon USB support of all things.

    It is a frickin' mainframe!

    Still, the article (if it is the same as the one linked to by ZDNet UK) does point out some things that need to be fixed in future Linux mainframe systems. Solidity.

    I believe that the future is bright for Linux on mainframes. The article assumes that Mainframes will be deprecated in the future by commodity x86 hardware, whereas they will equally get more powerful and require an OS to handle that power well, and IBM recognise the value of Linux in this respect.

  18. OLTP for Linux by Animats · · Score: 5, Informative
    The classic "on-line transaction processing" (OLTP) for which IBM mainframes are optimized is badly explained. The easiest way for UNIX people to understand it is to imagine an OS whose main job is to run CGI programs.

    Much server work looks like this: request comes in from network, appropriate program gets loaded, maybe talks to a database, runs for less than a second, returns results to network, exits. Typically, a large fraction of the resources used go into the "appropriate program gets loaded" step, doing the same startup ritual over and over.

    There are two UNIX/Linux solutions to that startup overhead problem. One is to build the transaction program into the network application (as in Apache/mod_perl/php). Note that this uses an interpreter to protect the network application from bugs in transaction programs, which is a major performance hit.

    The other approach is to use the regular UNIX/Linux program launch facilities to run a separate program for each transaction (as in CGI programs.) This is safer and easier to maintain, because the CGI programs each run in their own processes, but the cost of program loading (which might include initializing a Perl or Java environment) often dwarfs the cost of doing the useful work.

    A mainframe transaction processor basically maintains process images which are ready to run a transaction, with all loading complete. When a process is needed to run a transaction, it's made by copying one of those process images (with read-only or copy-on-write sharing of pages) and launching it to do the job. The new process runs for a short period and exits. This is a facility that Linux/UNIX lack, because they were intended for interactive use, not server-side transactions.

    Because Linux has copy-on-write semantics for fork(II), it's should be possible to do a high performance transaction facility under Linux. A transaction program initializes itself by loading everything it needs, but without any per-transaction data available. It then goes into a loop waiting for work, and on each request, forks off a copy of itself to do the job. Each copy does one transaction and exits. If it crashes or gets corrupted, only one transaction is affected. Note that there are no expensive exec(II) calls involved in starting a new transaction.

    Has this been done? It's obvious enough that somebody has probably tried it.

    1. Re:OLTP for Linux by gorilla · · Score: 2
      Fork & Copy on write is still quite expensive in terms of resources, if you're going for high performance you really want a non-forking model.

      The model you describe is basically that used by NCSA httpd, at the time that Apache split off. Apache was redesigned to do it's forks basically at startup time, and then load balance between looping httpd's. This gave much higher performance.

    2. Re:OLTP for Linux by Anonymous Coward · · Score: 1, Informative

      Does undumping a core file count? Emacs is the most obvious example.

      Emacs is really a lisp iterpreter with a substatial runtime. If you had to wait for emacs to bootstrap from the core lisp runtime every time you called exec("emacs"), you could wait a long time. So when installing emacs, you build the core emacs (as temacs), it runs, and dumps core once it has loaded everything you want in the basic install. Then you run undump, and get an executable.

      With the disk image cached, startup is basically just creating a process context, mapping the pages, and bringing up X (skip this part for transaction processing ;-).

      Obviously this is at the application level, and constrains application startup (no handles to external resources), but could probably be hacked into the kernel without to much trouble.

      Michael

    3. Re:OLTP for Linux by angst_ridden_hipster · · Score: 2
      A mainframe transaction processor basically maintains process images which are ready to run a transaction, with all loading complete. When a process is needed to run a transaction, it's made by copying one of those process images (with read-only or copy-on-write sharing of pages) and launching it to do the job. The new process runs for a short period and exits. This is a facility that Linux/UNIX lack, because they were intended for interactive use, not server-side transactions.

      Maybe I'm an idiot and am completely misunderstanding you, or maybe your analogy is breaking down here, but it seems to me that there is a Linux/Unix analog. For this kind of situation, you can do like many Unix servers do, and create a pool of processes with one controlling/listing process that uses IPC to hand off requests to them. This can drop the startup costs significantly, even if the child processes get swapped out.

      A prime example of this kind of usage can be found in Apache. And it's not overwhelmingly difficult to write a high-performance server, combining such a multithreaded controller with pool of child "transaction" processes. Heck, I've done it myself.

      --
      Eloi, Eloi, lema sabachtani?
      www.fogbound.net
    4. Re:OLTP for Linux by MrCynical · · Score: 1

      It sounds like you are describing CICS. But the time cost for loading programs is actually very low. CICS caches transactions. Programs that get used often remain loaded and are only unloaded when they are not used or the request queue rolls them off due to high varied transaction activity. It is really quite efficient.

      --
      --Scott 8-}
    5. Re:OLTP for Linux by JohnZed · · Score: 2

      Yes, someone has tried this. It's called a fork-per-request server. However, preforking servers (the style used by Apache 1.x) tend to perform much better. You should check out Unix Network Programming by Richard W. Stevens. It has an excellent breakdown of the various server concurrency strategies available under Unix operating systems.
      --JRZ

    6. Re:OLTP for Linux by Anonymous Coward · · Score: 1, Interesting

      I think the best that's been done is called the 'tacky' bit (chmod +t) on an executable. Traditionally, that left the executable loaded "in swap", presumably for faster startup.

      Implementations vary, and some are literal in that they were little more than a 'cp' from the filesystem onto the swap file and not much else. Some support shared libs, some don't. With big cheap memory, hitting a cached filesystem was far faster than even a linear read from the swapfile. Some were so bad, the +t bit would generally slow performance.

      Virtual memory systems, such as DEC's VMS, viewed all executable code files as if they were little swapfiles and would always share image pages on a copy-on-write basis. In effect, the OS opened the image file once for all users on the system. You could also tell the OS to pre-load it by fixing it in your choice of either virtual or physical memory.

      I believe Linux is has a partial implementation. It does share resident executable pages across active processes. It might also do something creative with the +t bit, but I have no idea of the implementation. I don't think it has a "complete" implementation, in that you can not pre-load images or fix an image into physical memory, and I don't think it "learns" anything from the first activation experience to speed later ones.

      Reading machine code blocks from disk is only part of the 'image activiation' problem. Page tables have to be grown, zero'ed memory has to be allocated, shared resources/libs have to be mapped, etc.,etc. In some cases, if you can pre-load, the system learn by pre-building any number of data structures that can speed multiple re-activations.

      Then again, the fastest way to design a maximal performance facility is to activate and initialize both the image, and program logic itself, only once. You can then use IPC type tools to exchange requests with it.

    7. Re:OLTP for Linux by JohnZed · · Score: 2

      Oh, hey, I forgot an important point about why fork-per-request isn't as reliable as the mainframe method. Mainframes handle requests separately to guarantee consistency and reliability by giving each request the same execution environment. However, in the fork-per-request model, there's still a central process that touches each request and is vulnerable to change. Imagine, for a trivial example, a case where the central process keeps a counter of requests handled so far. Clearly, this changes with each request and it's vulnerable to standard bugs (say, overflow errors). This sounds stupid, but it's a real problem, especially as you handle large numbers of complex and varied requests, since the amount of work done by the central process quickly becomes nontrivial.

      On the mainframe, this "central process" would be replaced by something like CICS, which has a ridiculously long track record of testing in hundreds of mission-critical environments around the world. It also includes a lot of highly-reliable features to automate common OLTP tasks, to eliminate yet another source of bugs.

      Basically, what I'm saying is: mainframe software infrastructure is really, really reliable. Way better than Linux. If you need an OLTP system that runs on a mainframe and doesn't crash, use OS/390, not Linux.

    8. Re:OLTP for Linux by skidrash · · Score: 2, Interesting

      You're looking for 'pinning' or 'the sticky bit', the ability to tell the OS,

      "load this executable image in memory and keep it there, next time someone asks for this program use the loaded image, DO NOT LOAD A NEW IMAGE from disk"

      This was a manual optimization for early UNIXes. I don't think any modern UNIX uses the sticky bit in this way because that's an optimization that naturally falls out of the page aging algorithms.

    9. Re:OLTP for Linux by maraist · · Score: 2
      Just a nitpick (since I agree with your general point).
      However, in the fork-per-request model, there's still a central process that touches each request and is vulnerable to change.


      In pre-forking, process A sets up its environment which includes the service port, and a shared memory segment (often just a a simple memory mapped file). Then it creates a bunch of worker forks. At this point, the master could simply do a ps once every second and see if it's children have died, but usually the shared memory is used to communicate activity to the master.

      Since all the forks maintain the file-handles, anyone of them can accept a job request. Thus they can be truely independent, and your issue of a corruptable monitor doesn't apply. (Except in the case that crashed workers need to be replaced by the monitor; but I feel that you were saying something different).

      It's true that sharing information between the workers and the monitor has a potential for corruption, but I'm not seeing how mainframes avoid this (except if you're saying that the functionality normally handled by programmed IPC is relegated to other tasks).
      --
      -Michael
    10. Re:OLTP for Linux by Cally · · Score: 2


      There are two UNIX/Linux solutions to that startup overhead problem. One is to build the transaction program into the network application (as in Apache/mod_perl/php). Note that this uses an interpreter to protect the network application from bugs in transaction programs, which is a major performance hit.


      I'm sure others will point this out too, but this just isn't true of mod_perl, at least (I can't speak of PHP, I've never used it.) Checkout the benchmarks in Stas Bekmann's mod_perl User Guide. Skinny: application code under mod_perl is compiled once, the first time it's accessed, and thereafter runs at (in effect) the speed of any Apache - modulo database, network, or bad code -related bottlenecks. I can't imagine any way of having a network accessible program be scalable, short of starting from scratch (no generic httpd) in C. You notice all those "http://www.foo.com/dynamic/foo.c?arg=val" type URLs? No, neither did I...
      --
      "None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
    11. Re:OLTP for Linux by vrmlguy · · Score: 2
      There are two UNIX/Linux solutions to that startup overhead problem. One is to build the transaction program into the network application (as in Apache/mod_perl/php). Note that this uses an interpreter to protect the network application from bugs in transaction programs, which is a major performance hit.

      I'm sure others will point this out too, but this just isn't true of mod_perl[...]

      What part isn't true? Perl compiles to an intermediate language, which is then interpreted. Yes, in mod-perl the application code is compiled the first time it's needed, but it isn't compiled into machine code, it's just turned into B-code, something that's more efficient to interpret that the original source. This is more efficient that CGI, where the compilation gets done over and over, but the B-code still gets interpreted with each request.
      --
      Nothing for 6-digit uids?
    12. Re:OLTP for Linux by vrmlguy · · Score: 2
      A difficulty in discussing this is that there's a breakdown of terminology. Unix invented the idea of seperate "fork" and "exec" primitives. All other OSs at that time only had a primitive which was very similar to the run-time "system" call.

      As I recall from the brief time that I did CICS programming, it was very similar to CGI programing, except that you weren't in a distinct process. Your program was running as something similar to a thread in a non-preemptive environment. Transactions were invoked and they ran uninterupted until they needed to perform I/O, say to the database. At that point, the thread was reassigned to another transaction's code. (I wanted to say that the thread was killed, but that's not accurate because it implies start-up/shut-down costs that just weren't there.) When the results of the database call were available, the transaction would be resurrected to process the data and transmit the results to the end-user. The whole process was designed to maximize throughput, but it required a coding style that was similar to writting CGI for Win-16. ;-)

      --
      Nothing for 6-digit uids?
    13. Re:OLTP for Linux by Tony-A · · Score: 2

      mainframe software infrastructure is really, really reliable.
      That's the intention and the attempt. That's what you're paying for. YMMV.
      Things may have changed since, but CICS used to run all of it "joblets" (whatever they were called) in a single process which could be taken out by a single bad module (like any FORTRAN program).

    14. Re:OLTP for Linux by Anonymous Coward · · Score: 0

      Thank you for putting the time ad effort into writing that informative and well constructed post. I didn't know that before and I do now.

      cheers

    15. Re:OLTP for Linux by Animats · · Score: 2
      Mainframe OLTP systems can be thought of as operating systems that are optimized for fork-on-request servers. It's worth thinking about what would be needed in the kernel to make that type of server work faster. It's the cleanest server model, and offers good opportunities for higher security. Most transactions ought to run in a jail; all they can do is talk to whatever object they had open at startup. Then you don't have to worry about buffer overflows in CGI programs.

      The mainframe people have had this for decades, and it does have major security advantages.

    16. Re:OLTP for Linux by Anonymous Coward · · Score: 0

      something like this could be "hacked". It would need two parts: a "transaction daemon", and a "transaction processor".

      The transction processor would be a specialy written program that does a class of work. It would be a process that is always loaded (or at least does not close itself on completion) and only communicate with the transaction daemon. The daemon would send the job to the processor, and the processor would return a result to the daemon. After the job, the processor would then return itself to a known state and wait for next job.

      The transaction daemon would intercept job requests, schedule the jobs, and send the jobs to the proper transction processor. The daemon would have knowlage about the length of time the processor was expected to work, and could kill and restart a processor if a job does not finished on time. The daemon could start and kill extra processor of a type during a time of high demand. The daemon could talk to other daemons on the network and tell them to schedule jobs on their boxes (master and slave daemons?). The daemon could set the priority of processors that were not running to be very low. The daemon could start and stop classes of processors at certin times. The daemon could return a message to the requestor after a job completes or has been killed. The daemon could inform the requestor of job status on periodic bases. the daemon could give an estimated time to completion to the requestor.

      With a little more thought, you could build a nice batch subsystem out of many unix boxes. Maybe a batch subsystem on each user box that communicates with the main (master?) subsystem that then finds the best place/time to run the job (it could be right back on your computer). or the batch subsystem could be set with the $BATCH variable, or the local system decides if it can run the job before sending it to the master subsystem. There are a world of possibilities.

  19. Kids these days by wiredog · · Score: 4, Funny
    on my corporate mainframe...combo of NT and OpenBSD

    That ain't big iron! The only system that runs both of those is the Alpha. And the Alpha ain't a mainframe.

    1. Re:Kids these days by geekoid · · Score: 2

      good catch.

      --
      The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
    2. Re:Kids these days by Anonymous Coward · · Score: 0

      only system that runs both of those [NT and OpenBSD] is the Alpha.

      And the PPC. And the x86.

    3. Re:Kids these days by Anonymous Coward · · Score: 0

      NT doesnt run on PPC

    4. Re:Kids these days by juuri · · Score: 2

      It's good you posted anonymously, because you are wrong.

      NT Workstation/Server 4.0 run on PPC just fine (well asside from the lack of applications).

      --
      --- I do not moderate.
  20. Sun FUD Campaign by myst564 · · Score: 5, Interesting

    First of all, way to go Slashdot, this article has been out for quite some time. It's received a lot of attention on the Linux 390 mailing list as a Sun FUD campaign as it places a fully loaded z900 on par with 80 Dell servers and the zSeries in general on par with mid-range Sun equipment (and others).

    First, I'm fairly qualified to talk about what the zServer can do. For those of you who don't remember, I'm one of the guys that helped win a z800 for Clarkson University that will be used in our Open Source Institute. I'm also the technical lead for COSI (whatever that means ;) so it is my job to know about what a z800 can do for us.

    Some history, Clarkson University has always had a very good relationship with IBM: they employ a large amount of Clarkson students and graduates (including me, in the Extreme Blue program. So if you think that biases my opinion, well too bad as I've talked with the guys making sure that Linux runs and is fully integrated on the Linux platform and one of the original Linux S390 authors Boas Betzler.

    All of these people have real experience with what the zSeries can do, as do I since I've seen it in action. A zServer is unique in the sense that you can (with the right model) run Linux S390, VM, zOS and other guest operating systems in Logical Partitions. These all act independantly of one another just as if they were seperate machines on a network. This is great if you have DB2 with maybe a web frontend because both of those machines can talk at memory speed via HiperSockets and the only outside link is the network connection to the web server, which is at Gigabit speed (did I mention that you can do full speed gigabit with one of these things on multiple interfaces?).

    This article basically says that you can take a midrange Sun server and do everything that a z800 can do but much better. I don't know of any Sun Server that can run N Linux clients in a VM at full speed.

    They aren't the solution to every problem, but a zServer certainly is a better solution that what is presented in the article. I really don't have the time to go in to detail with everything as it's a lengthy article but suffice it to say that this is no where near 100% accurate.

    1. Re:Sun FUD Campaign by gorilla · · Score: 1

      . A zServer is unique in the sense that you can (with the right model) run Linux S390, VM, zOS and other guest operating systems in Logical Partitions. It's not totally unique. There are other virtualization systems, for example Vmware for x86. VM is definatly a much better implementation than Vmware, not least because guest OS's are now written expecting to be run on VM, but the concept is identical.

    2. Re:Sun FUD Campaign by myst564 · · Score: 1

      VMWare isn't even close. The zSeries by default has support for 15 (16 total, 1 reserved for the system) Logical Partitions. That's 15 different, independant Operating Systems being run simultaneously right on the hardware. Now, in each of those 15 LPARs you can run VM which multiplexes that LPAR's resources amoung the VM guest operating systems.

      VM has been around since the 60's, and is incredibly optimized: so much so that it's very close to actually running on the hardware.

      In the VM you have complete access to all devices on the zServer (assuming the guest OS has drivers for them). Can VMware do this? No.. could it, possibly... but it's no where near the maturity that VM is.

    3. Re:Sun FUD Campaign by finkployd · · Score: 2

      Furthermore, VMWare runs on x86 which is absolutly horrible at running virtual machines (arguably, it is horrible at the concept of multitasking in general). s/390 hardware on the other hand was designed for this, and has been optimized over a span of decades.

      Finkployd

    4. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      Dumbass. You're an old mainframe programmer aren't you? Go back to being an IBM bitch and let the people with brains do the thinking.

    5. Re:Sun FUD Campaign by cnladd · · Score: 3, Insightful

      "This article basically says that you can take a midrange Sun server and do everything that a z800 can do but much better. I don't know of any Sun Server that can run N Linux clients in a VM at full speed. "

      Please point out the point in the article where this is mentioned, because I don't recall this ever being said. :)

      As a matter of fact, there are several points in the article where the author mentions that Sun (and other, traditional UNIX solutions) are intended to be used for completely different purposes than mainframes. From what I've read, he doesn't seem to be saying "Linux on an z/Series system outright sucks". I see an article who's point is "Don't spend $5M+ on a z/Series with Linux when one (or several, or whatever) PC or Sun system will do.

      Looking at the sidebars from the article, it appears that this is just part one in a series of three. From some of the statements in these sidebars, it appears that the main focus of this is trying to cut through much of IBM's FUD and point out that Linux on the mainframe isn't always the right way to go. He specifically states that in the second part he'll cover the areas in which he feels Linux on the mainframe makes sense.

      Finally, as far as being a Sun FUD campaign, what the hell makes you think that? I haven't seen one shred of evidence to support that. Sure, he only has figures for PCs and Suns, but he states that it's because that's all he had access to at the time. He came right out in the clear and admitted that so that everyone reading the article can keep that in mind. Having worked on both Sun and HP systems, I'm convinced that - if the Sun statistics are acurrate - the stats will be similar on a similarly configured HP box as well.

      Now, just calm down a bit, okay? This is starting to sound like the arguments that I hear over the cube walls sometimes, with the mainframe folks cutting the UNIX and NT folks, and vice versa. This is the kind of crap that makes UNIX and NT folks think of the "mainframers" as a bunch of old bigots with blinders on. I think we all realize that different types of systems are valuable for different purposes, and most of us who read Slashdot regularly knows how to keep an open mind.

      --

      --
      Welcome to the land of the easily amused...

    6. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      Nice troll, cause Clarkson will know how to handle that. The point of the article that you are responding to is: Why run 16 Linux images on a mainframe!

      Mainframes and their operating systems are great for certain applications, but Linux generally isn't part of those applications.

      The main reason people would want to run 16 linux images on a computer would be as web/database servers.

      I feel that Price/Performance ratio for 80 rackmount x86 machines far outweighs that of aa zServer. Esp. when you consider all that they will be running is Apache and mySql.

      When you buy a Sun server, it's not made to run linux, it's meant to provide a high reliability _Solaris_ environment. Which is also a better Price/Performance ratio for some things.

      If I were to need to do massive amounts of financial transactions(i.e. a bank), then I'd use zOS on a zServer, certainly not Linux.

      Just imagine, go up to an ATM, and see:
      kernel looping
      last message repeated 3000 times

      or even:
      Oops!

      yeah,
      Troll this bisnatch

    7. Re:Sun FUD Campaign by nrosier · · Score: 1

      I don't know about Linux (has anybody any information about Linux on one of the Sun Big Irons?), but a Sun Starfire (E10K) can run up to 16 Solaris domains, a Star Kitty (SF12K) can run up to 9 and a Star Cat (SF15K) can run up to 18 (event to lower mid-frames have this possibility). It's not running N clients in a VM but running x different OS'ses on 1 platform.The number of domains you run is limited by the number of system boards, i.e. hard partitioning. And I don't know if it's through, but I've heared rumors that Sun is working on soft partitioning as wel, so you're not limited to the number of system board anymore.

      These domains can communicate with each other through their "Giga-plane" via IDN (Inter Domain Networking). So I guess they can communicate at Gigabit speed with each other.

      So Unix/Sun boxes might not be able to do exactly what a z800 series can, but the 2 things you've explained are possible in some way or another.

    8. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      Nah he's just a sexually frustrated clarkson guy who feels the need to make clarkson people look like morons ...

    9. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      Sexually frustrated and need to make yourself feel better by bragging on slashdot .... get out of potsdam.

      And who there is really going to know how to put it to good use? Serlman? tino? ... get a grip, learn how to actually program well rather than tinkering with expensive toys. Get a job outside of IBM because your seeing way to much blue. Linux is a hack OS .. sorry but it is. Go run a real OS a BSD perhaps.

    10. Re:Sun FUD Campaign by Tony-A · · Score: 2

      You won't see kernel messages on ATM machines. Mainframes don't use ATM machines for consoles, they use Selectric typewriters. Or at least they used to.
      You use mainframes for reliability and concentration, where something critical doen't work if it's distributed.
      80 rackmount x86 machines has better price/performance, at least until something like Chernobyl goes off in all 80 of them at the same time.

      Mainframes and their operating systems are great for certain applications, but Linux generally isn't part of those applications.
      Yet.

    11. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      and most of us who read Slashdot regularly knows how to keep an open mind

      (Score: +5, Funny)

    12. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      > I'm one of the guys...

      That's nice, now maybe you can help dispel the FUD rather than add to it. BTW, which FUD? You title your post "Sun FUD Campaign" then go on to whine about Dell servers.

      Last I checked Sun and Dell were, well, rather distinct outlets.

      > I don't know of any Sun Server that can run N Linux clients in a VM at full speed.

      I don't know ANY machine that can run N clients in a VM at "full speed". By definition, when N=2 the system can only run each of N at 1/2 speed. Don't get pesky about MP-ness and such, I've got that down already.

      > They aren't the solution to every problem...

      We guessed that too. I don't use one to surf, for example. Too big and heavy to sit on the arm of my couch, you understand.

      > did I mention that you can do full speed gigabit with one of these things on multiple interfaces?

      Yes, I'm hear you can run something like 24 or 30 of 'em, if I use all the available channels for Ethernet. But, with 80 Dell's I'd think I could run 80 of 'em, and still have room for disk I/O controllers.

      > a zServer certainly is a better solution that what is presented in the article. I really don't have the time to go in to detail with everything as it's a lengthy article but suffice it to say that this is no where near 100% accurate.

      Really?

      Gee, moded to '5' and contains eactly zero new or useful info, and does absolutly nothing to confirm or disparage the original post. How /.

      So, your argument seems to be...

      1) I'm important.
      2) I know, 'cus I do.
      3) It's FUD, I tell you.
      4) Ain't got time, see 1.

      Not bad, for a Clarkson guy I guess.

    13. Re:Sun FUD Campaign by dinotrac · · Score: 1, Flamebait

      I don't know. Looks like a FUD campaign to me.

      Part 1 of the article (series) made a big deal of the 41,400 demo -- that nobody has tried to say is realistic.

      That's ok, but Murphy got ridiculous in trying to intimate that each of those images had an 8 megabyte working set and that swapping those images in to handle timer pops would generate 30 gigabytes per second -- or maybe it was 30000 gigabytes per second, I don't remember -- of paging activity. Trouble is, apache and Linux together might have that big a memory footprint, but idle processes will have a much smaller working set, one measured in kilobytes. Each image will demand page only those pieces of the address space required to process the work being done. I don't think the interrupt handler and dispatcher and apache's own dispatch loop occupy that much code.

      In the second section, he talks about workloads losing randomness as more and more work gets piled on. The opposite is true: they gain randomness. He's certainly right that interactive workloads have definite patterns of peaks and valleys, but that's very different from losing randomness in very small time increments, and it is that randomness that lets a mainframe (or any large processor -- including Unix) do more with less horsepower than clusters.

      There's a lot in his article that I don't understand, but his treatment of things that I do understand leaves me unwilling to trust the rest.

    14. Re:Sun FUD Campaign by Anonymous Coward · · Score: 0

      hey just like every other place clarkson has a few jackass's ... not everyone from clarkson has "big blue" view of the world.

    15. Re:Sun FUD Campaign by gorilla · · Score: 2

      So what you are saying is that it's a better implementation. Which is exactly what I said.

  21. *Revised* Version by FlowerPotAdmin · · Score: 1

    At least this site will inform the user that story content has changed...

    --
    -Justin
    That's enough posting for now lads, there're trolls afoot.
  22. Re:finally by gorilla · · Score: 2
    , was ported to the 486 and Pentium by GNU

    No it wasn't. GNU is a license, and licenses are notoriously bad for writing code (or doing anything except sit on a disk or shelf). Linus wrote Linux for the 386, but there was nothing stopping you running it on the 486 even on day 1. In fact, even today, you can run 386 code on a Pentium IV. The only disadvantage is that you'll not get the best optimizations. The GNU license was applied for version 0.12 in Jan 1992, before it was really a practical OS, and in March 1992, it became 0.95, and was really a usable OS.

  23. Mainframes and NT... by cr0sh · · Score: 1

    He doesn't say what mainframe he was using, but IIRC, there exists for RS/6000 and AS/400's (yeah, I know the RS/6000 isn't really a mainframe) "co-processor" boards that are essentially funky PC motherboards that run the PC-based OS (in this case, NT), and have drivers to use the mainframes resources (drives, ports, etc) and translate them into the PC equivalents.

    Most of the time, these boards have their own memory - some even have thier own hard drives (I would imagine there are some which are simply a TN5250 hack for comm with the mainframe, and only draw power from the backplane - all memory, ports, and drives mounted to the module).

    In other words, NT doesn't actually run on the mainframe, or VM - but rather on a dedicated processor board. I know these solutions exist for IBM hardware - I wouldn't doubt that there are similar solutions for other mainframe manufacturers as well (either by the manufacturer or licensed third parties).

    --
    Reason is the Path to God - Anon
    1. Re:Mainframes and NT... by Anonymous Coward · · Score: 0

      ..and neither is an AS/400.

      You're just making stuff up, aren't you.

  24. Re:William Shatner by geekoid · · Score: 2

    darn, I had hoped to get "+1 funny", but I got "-1 not funny you star trek goof" instead. oh well.

    --
    The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  25. Re:finally by Anonymous Coward · · Score: 0

    I think that.

  26. It won't work here. by forged · · Score: 1
    I don't believe student dorms have either the floor space or the electrical power to handle an IBM mainframe..... and, there is no plumbing available for cooling !

    I guess I'll stick with my old P-200 for the moment....

  27. Re:Linux Sucks! by Anonymous Coward · · Score: 0

    You forgot:
    3) Bitch about it on Slashdot because you apparently are not working now!

    :-)

  28. Puzzling claim, somewhat buried by clem.dickey · · Score: 2
    Skipping to the middle of page 6:
    In the Unix world, however, processes are not created. Processes spring magically into existence and start to run when their contexts are loaded. As a result, most Unix CPUs have hardware context management allowing them to completely switch processes within one instruction cycle -- or even to run more than one instruction stream concurrently.

    I'll grant the point of the paragraph - that UNIX process/destruction occurs more often that MVS address space creation or even task creation. And I'll buy that some "UNIX CPUs" can handle multiple instruction streams. But have any really implemented a single-cycle context switch?

    1. Re:Puzzling claim, somewhat buried by Anonymous Coward · · Score: 1, Informative

      I know IBM has demonstrated this with some of their next generation PPCs. Alpha has had single-cycle context switch for years (I don't know if tru64 or alphaLinux supports it, but OpenVMS does.)

    2. Re:Puzzling claim, somewhat buried by vrmlguy · · Score: 2

      I scratched my head over this as well. SPARC processors *do* have the ability to switch between user and kernel contexts in a single instruction. This includes pushing and popping the registers on a special hardware "stack" (see this for more info). This might be what he was talking about.

      --
      Nothing for 6-digit uids?
  29. 31-bit mode by ortholattice · · Score: 2
    From the article: As of February 26, 2002 IBM said: [...] The Linux code to exploit the 64-bit architecture will be available from the IBM developerWorks Web site later. Linux for S/390, currently available on G5, G6, and Multiprise 3000 processors, will be able to execute on zSeries servers in 31-bit mode.

    I checked, and yes, the IBM site did say "31-bit" mode. Won't this break a lot of Linux apps?

    1. Re:31-bit mode by myst564 · · Score: 1

      In short, no ;) However, with the z800 0LF announced IBM has support for full 64bit in the kernel (there are some restrictions in certain situations). But you can choose.

    2. Re:31-bit mode by finkployd · · Score: 2

      Nope, linux apps run fine on it (obviously, since quite a number of large companies are doing it).

      Interestingly, the reason for this 31 bit addressing is rather funny. When IBM mainframes went from 24 bit to 32, programs that were designed to run in the 24 bit mode ("under the line", as we say in the biz) needed to use 24 bit addresses and could not deal with larger addressing. The missing bit is used to denote whether the address is 24 bit or 31 bit.

      Finkployd

    3. Re:31-bit mode by HiThere · · Score: 2

      Great! So at some point they can just declare that 24 bit addressing is obsolete, and use that bit as a switch to 63 bit mode. Or maybe the new addressing scheme should reserve the top two bits, and then they could choose between 31, 62, and 126 bit addressing modes.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
    4. Re:31-bit mode by Anonymous Coward · · Score: 0

      What, and break 40 years of backward compatibilty?

    5. Re:31-bit mode by Tony-A · · Score: 2

      Makes a good myth, but no.
      This is working from the old stuff forward, so I may be missing something about the new stuff.
      Addressing is done by a 0-4095 byte displacement from a base register (of 1 thru 15). There is an RX mode that uses both a base and an index register (from same set)
      The standard IBM calling sequence for FORTRAN, COBOL, PL/I, etc. typically by BALR 14,15 after loading GR 15 with entry point.
      GR 13 points to a register save area, typically in the body of calling program. Non-Recursive.
      GR 15 points to the Entry Point in the Called Program.
      GR 14 points to the Return Address in the Calling Program.
      GR 1 points to a parameter list. Successive addresses. Last parameter is marked with high bit set.
      Probably one or two other changes. Pretty transparent, actually, unless you do things like tag bits in the non-address part of an address register.

      The 31/24 is a PSW thing, like the ASCII/EBCDIC bit.
      In 31-bit mode, the old condition code from BALR has to be stored somewhere else.
      LA (Load address does not necessarily zero the high-byte).
      Format change in the PSW (Program status word)

  30. User needs? no no no by pommiekiwifruit · · Score: 1

    Mainframes - designed for the benefit of the machine.

    PCs - designed for the benefit of the user.

    Unix - designed for the benefit of hunt-and-peck administrators and obscure language designers.

    1. Re:User needs? no no no by Pauly · · Score: 1
      Unix - designed for the benefit of hunt-and-peck administrators and obscure language designers.

      You're right. C is so very obscure. Hardly any software in use today is written in C.

    2. Re:User needs? no no no by Anonymous Coward · · Score: 0

      "Hardly any software in use today is written in C."

      Outside of the UNIX world, that's true.

    3. Re:User needs? no no no by jo42 · · Score: 1
      > You're right. C is so very obscure. Hardly any software in use today is written in C.

      Thank you for re-enforcing my assertion that no one runs Linux. Or NT. Or Windows 2000. Or Windows XP. Or Solaris. Or Irix Or...

    4. Re:User needs? no no no by Anonymous Coward · · Score: 0

      The shop that I work for writes all of our windows, mac (not so much anymore), and unix (linux, and solaris) software with C---not c++ or any such bs, C.

  31. Re:finally by karmawarrior · · Score: 1

    To respond to you both:

    The GPL is the licence you're thinking of.

    GNU is the name of the operating system project started by Richard Stallman. It is not a "group" that "ported Linux to the 486" or a "licence". The first functional implementation of GNU was created by Linus Torvalds when he ported GNU to run over his Linux kernel. The fact that this combination is largely GNU software yet is called "Linux" is the bone of some contention from Stallman and others who worked on GNU, but that's another thread.

    Have I been trolled?

    --
    KMSMA (WWBD?)
  32. Re:try a real operating system by Anonymous Coward · · Score: 0

    Would that be the BeOS zealots?

  33. Linux Journal Article by Erik_Kahl · · Score: 1


    This article was in linux journal about two years ago, but most of the discussion is still fairly interesting to read. He brings up a lot of very good points and has some interesting numbers to back him up.

  34. Report roasts linux on the mainframe by nadiizu · · Score: 2, Insightful

    There is another article on ZDNET link that roasts Linux on the mainframe. I think people were too harsh toward sun when they published their report, but the reality is that Linux is not ready for the mainframe YET.

    1. Re:Report roasts linux on the mainframe by Anonymous Coward · · Score: 0

      True, very true. Furthermore, it is a waste of time to try and reinvent and reimplent what's already available in FreeBSD. Linux has set back the state of computing by 10 years. Linux is a real travesty that has befell the OS community. We must speak out and get the word out that BSD is freely available and technically superior. There is no need to run nor develop *linux.

    2. Re:Report roasts linux on the mainframe by Anonymous Coward · · Score: 0

      Do not believe everything you read on ZDNET. ZDNET is in bed with Microsoft and is getting paid off to say nice things about Windows and trash Linux. There are many SuperComputers and Clusters that do critical work that use Linux so do not believe the FUD. Bill Gates in his last stand is doing everything he can do discredit Linux but it will not work the truth is out about the little Penguin that can scale. ZDNET FUD sponsored by Bill Gates and Microsoft. If you read ZDNET you must still use Windows because thats where all the dumb ass script kiddies go to get the latest news on Visual Blow Job VB Shit. Windows is for dumbshits and please lets not dumb down linux for Windows dumbshits if you want a real OS like Linux you are going to have to RTFM and BASH. FSCK OFF Bill Gates take your weasel OS and shove it up your big fat behind WinBSOD Data Center is a crock of shit and cannot scale. Would you sleep well if your data was running on Bill Gates Virus Crashware.

  35. My biggest gripe with.... by dorker · · Score: 0

    mainframe Linux is that most mainframes don't have USB ports or good drivers. This sux cause then I can't plug in my Canon Powershot digital camera and use the pictures to make christmas cards for my grandmother. Also, Printshop Deluxe doesn't run on my S/390. SUX

  36. My Experieces by FJ · · Score: 5, Informative

    I work for a large shop and here are my experiences running Linux on the Mainframe.

    First, I'm a mainframe person. I like the mainframe. I've used Linux at home for about 6 years so I was chosen to be on a "proof of concept" with running Linux under VM. I've been doing OS/390 & z/OS support for about 4 years. I'm in the "30 & under" crowd and I've seen both the Unix & mainframe side of support.

    We've played with TurboLinux, SuSE, & the RedHat beta for the zSeries. We're running zVM 4.2.

    First, lots of things work really well. It was strange seeing the normal Linux boot messages appearing in zVM. We've been primarily using the 2.4 series kernel, but we have tested things with the 2.2 series. We've played with Oracle, WebSphere, DB2 Connect, Samba, Apache, IBM HTTPD server. The only technical problem we really had was Samba caused kernel crashes. Some patches from the IBM z/Linux site fixed it.

    The biggest problems we have had are philosophical and percepteion based. Here are some of the difficulties:

    We had to force our customers to a shared outage window. Even VM needs to be IPLed every year or so. If they can't tolerate a 6 hour window every quarter or 6 months, we won't support them on the zSeries. A second box could make it a true zero downtime machine, but we are initially targeting the low usage, non critical machines.

    Lots of people have the delusion that the zSeries processor is hundreds of times faster than other processors. It isn't. It's fast, but not several magnitudes faster than the other processors out there. It's also not designed for heavy computational applications. Don't try, you'll hate the results. It can be done on a limited basis, but don't try and compute PI. It works better on I/O related applications which are traditional mainframe strengths.

    A lot of the code on the zSeries for Linux is the first generation to be released there. A lot of the performance perks for that platform are not there yet. If there is enough adoption, ISVs will make the performance better, but right now a lot of them are testing the water.

    Some people have the illusion that if you take a piece of crap application on Solaris or NT and run it on Linux, it will run better. The OS typically doesn't make your piece of crap any better.

    When people buy an Intel or Solaris server, they typically get the most memory & disk space they can afford. This is the worst thing to do under VM. We had a lot of people want 2GB of RAM and 100GB of disk space. Later analysis showed they could survive with much less memory (some as little as 128M) and used almost none of the disk. The reason for this is simple. Whey you buy a Sun or Intel server, upgrading them is a pain, so you do the pain up front. Under VM you can change the amount of memory & allocate more disk very easily. This was a big learning curve for people, and not just the Unix people. The major difference we found in the memory is because Linux uses it as disk cache. On the zSeries the hardware has lots of it's cache on on it.

    People needed to understand they were sharing CPU & memory. Performance tuning has a very big impact. On Intel or Sun who cares if your application is looping endlessly. On VM everyone cares. Lots of our Unix sysadmins really hated this fact and the customers couldn't fathom it. You want to put applications with LOW USAGE on this platform. The idea behind sharing is that nobody needs all of the CPU all of the time. If you run at 100% on a 4-way Pentium CPU, you won't like sharing CPU with dozens of other virtual servers and they won't like sharing with you. This was probably the most difficult thing to stress to the users.

    This isn't emulating Intel. It took a while to get people to understand that VM wasn't emulating an Intel machine and that the nice pre-compiled intel binaries don't work. Lots of people went out looking for software from ISVs and the ISVs said "Sure we support Linux". What they didn't say is "We support Linux/390". There is a very big difference. Linux is not just Linux on Intel and it took some education to get this through to the users.

    Once we convinced people that it isn't running Intel, they tried to recompile their favorite programs and found out that for some applications a "simple" recompile wasn't enough. I would imagine that the power-pc folks had similar problems, but some programs take a little investigation.

    There were some really nice aspects of running on a zSeries.

    Disaster Recovery is easier. Mainframe DR has been established for decades and it isn't terribly different with Linux on the mainframe. Much more simple than having dozens of individual machines to recover.

    The hardware never fails. It may be expensive, but CPUs have a 30 year mean time to failure, the disk is all raid, multiple IO chanels help ensure there is not single point of failure. Hardware can typically be swapped out without taking an outage. CPUs can by dynamically added.

    If you want to copy an existing virtual server and make a test copy, that can be done in minutes. That makes it really nice for developers who want to do the "what if I do this" tests.

    VM's programmable operator facility makes for some nice system automation. You can also create Rexx scripts for your operations so they never even need to logon to Linux to do certain work.

    Creating a new server is easy. No more running through the install screens. Once you have one customized, just use it as a template for new servers.

    We were able to have certain drives shared as read-only across all images. This makes support a little easier. We made one Linux have the drive read-write. When we changed it there, we just unmounted & remounted it on the other images (a Rexx script made that painless) and it was magically everywhere. We can even take down the read-write linux to be sure something isn't accidentally changed. We've been experimenting with sharing lots of Linux mount points this way. We estimate we can concentrate about 100GB down to 2 GB which cuts down the overall cost. The majority of code on all Linux images are the same and will tolerate being shared, so as long as your environment is stable and you do some planning, you can dramatically cut down on disk usage. The amount of disk you save is directly related to the number of images your machine can handle.

    The virtual-linux to virtual-linux IP traffic happends at memory-to-memory speed. It's also very nice not to worry about network issues when trying to debug a problem because there is no physical network.

    Recovery is easier if an image won't boot. Just attach the drive to another, running image and fix the problem. No need to physically go to the machine.

    Sorry to ramble, but this is what we have found. Linux on the zSeries has it's place and does work, but it's not a solution to every problem. Few things are.

  37. asych I/O by Anonymous Coward · · Score: 0

    I believe many of the scalability problems are also
    due to no asych I/O , at least for db apps. I believe they are implementing it in linux 2.6, though

  38. thats because by Anonymous Coward · · Score: 0

    it is relative to enerprise OS's not pieces of shit like windows

  39. offtopic by Anonymous Coward · · Score: 0

    soory but BeoS is not a good server OS. youre beef is with KDE and GNOME

  40. TCP/IP Stack by Anonymous Coward · · Score: 0

    What's wrong with it? It has worked very well for me and many other people I know. Very low latency, low overhead, good bandwidth, support for most of the new TCP and IP options.

    Are talking about things like VLAN support, massive numbers of device aliases, or strange hardware like token ring -- or what?

    1. Re:TCP/IP Stack by Anonymous Coward · · Score: 0

      The Linux stack is the red headed stepchild in the world of TCP/IP. Almost any other stack in common usage is derived from the BSD code, as should be the case. There don't need to be additional implementations. It doesn't make sense for there to be. The whole point in BSD is to act as a reference for that sort of thing.

      But Linus 'didn't like the BSD stack' for some arbitrary reason so some other kludge was thrown together, and now Linux is the weird odd-man-out on the net, as a whole.

    2. Re:TCP/IP Stack by Anonymous Coward · · Score: 0

      Arbitrary, yes the fact that the BSD license was incompatable with the GPL had nothing to do with it.

  41. Alpha? by theendlessnow · · Score: 1

    Isn't that the old processor that HP used to make?

    1. Re:Alpha? by AdTropis · · Score: 1

      No. HP's RISC CPU was the PA-RISC. I haven't really studied that architecture very much, so I can't really tell you much about it.

      On the other hand...

      The Alpha CPU was a 64-bit processor manufactured by DEC. As you probably already know, DEC was purchased by Compaq, which is now joining forces with HP. The single most talked about feature of the alpha was it's floating point performance. Though I can't produce the numbers myself, it supposedly beat any other hardware platform by quite a large margin in the floating point department (even at significantly lower clock speeds). The typical uses seemed to include scientific applications.

      Also worthy of note: Alpha's can currently run many OS's. The "official" OS's include Tru64 Unix (previously OSF/1), Windows NT 4.0, and OpenVMS. You can also run FreeBSD (which is on my alpha), NetBSD, OpenBSD, and Linux.

      Though I never ran it myself, Windows NT for alpha was supposed to be quite interesting. The actually code you ran was made for the x86 platform, but special software translated the x86 instructions to alpha instructions. The first time you ran a program, this process was very slow. However, the more you ran a program, the more the translator was able to optimize the translated code. Quite an interesting way to keep things portable.

    2. Re:Alpha? by Anonymous Coward · · Score: 0

      Can I run MS_DOS on HP's Alpha processor?

      What's a poor hand-me-down 64 bit chip to do??

    3. Re:Alpha? by Anonymous Coward · · Score: 0

      That's not strictly true. The alpha version of NT was native - all that had to be implemented separately was the HAL (Hardware Abstraction Laye)r) What you're referring to was a feature whose name currently escapes me, which allowed running x86 NT binaries on the alpha. It did, as you say, radually migrate the x86 code to alpha.

    4. Re:Alpha? by jo42 · · Score: 1
      > Windows NT for alpha was supposed to be quite interesting. The actually code you ran was made for the x86 platform, but special software translated the x86 instructions to alpha instructions.

      Bullshit. Windows NT 4.0 for Alpha was native Alpha code. As was a pre-release version of Windows 2000 for the Alpha chippies.

    5. Re:Alpha? by AdTropis · · Score: 1

      yes, the OS was, but you could run x86 apps on an alpha without having to find the proper port.

  42. 70% of data by Anonymous Coward · · Score: 0

    sorry bud, but mainframes run 70% of corporate data still.

    check out
    http://www.esj.com/departments/article.asp?Edito ri alsID=59

    1. Re:70% of data by Anonymous Coward · · Score: 0

      wierd I did it but it bouces back to their home page. oh well, its in there somewhere ;-)

  43. Wrong audience by Anonymous Coward · · Score: 0

    Let's take a reasonable guess: the average Slashdot user has no experience whatsoerver with mainframes or corporate data centers. Better stick to stories about ATTACK OF THE CLONES and so on. At least those topics offer something within the life experience of the average /. reader.

    1. Re:Wrong audience by Hyperfrog · · Score: 1
      Actually, this is the perfect audience.

      My company uses mainframes, we also have websphere, linux, java, NT (etc)... so I'm VERY interested in any developements in this realm.

      Thanks for asking.

      --
      Move faster
  44. TMPFS by Julian+Morrison · · Score: 1

    "I think the best that's been done is called the 'tacky' bit (chmod +t) on an executable. Traditionally, that left the executable loaded 'in swap', presumably for faster startup."

    To get this effect cheaply and repeatably in Linux, copy the relevant binaries under a tmpfs mounted directory.

    1. Re:TMPFS by Anonymous Coward · · Score: 0

      Thanks, I know. I was tring to read down some history for what seemed to be a poster lacking therof.

      BTW, the effect of tmpfs is not exactly the same. The file must still be "read" from tmpfs into executable pages, thus there are two copies kept in the VM. But, as I said, implementations varied remarkably so using tmpfs is likely as good or better as any other.

      IBM's own software products demonstrate that the MF rends from "tradional" thinking, similar to UNIX. The fact DB2, CICS, MQ, etc. etc. ported so quickly from the MF to Linux et. al. is the platforms aren't all that different. A MF is just another knockoff 16 way SMP box, with an intellegent I/O co-processing subsystem, and its own wacky instruction set.

      So, the fast answer is, I think...

      An IBM TSR (Terminate and Stay Resident) program, like DB2 or CICS, "terminates" just like it does when it blocks in Linux.

  45. from ZDnet by Jonny+Ringo · · Score: 1

    Market research company Meta Group takes a swing at Linux, saying that Linux mainframes will soon be irrelevant and that the OS isn't mature enough to handle critical business applications.

    Your the one that not MATURE!

  46. Re:finally by Alexander+Poquet · · Score: 2, Informative

    Not to be a GNU pundit, but...

    > And GNU has nothing to do with porting of Linux to any platform.

    ... is demonstratably false. Whether or not the individual people who port the Linux kernel to a new architecture are or are not GNU affiliates is, simply put, irrelevant. The first step to getting Linux (or BSD, or whatever) on a new system is porting GCC to its architecture. While this is sometimes done by the people responsible for the Linux porting effort, most of the time this is done by members of the GCC team -- getting a new port to work without breaking all the others requires a great deal of cooperation and support.

    Not to mention a working linker. Assembler. The list goes on. Who wrote those?

    Lately I've heard a lot of Linux weenies dissing GNU and RMS as out-dated hippies who are prone to overestimating their importance. Unfortunately for these people, GNU is the only reason Linux exists. It's not like Linus wrote his kernel and there just happened to be a binutils chain, compiler, libc, etc just sitting there, ripe for the taking without someone doing a HECK of a lot of work. Probably more work than goes into developing the Linux kernel itself.

    Unlike some morons, I'm not here trying to say that Linux/Linus don't deserve a lot of credit; they do. But people who disagree with RMS and his policies often decide that that makes it okay to write revisionist history and downplay his importance to the OSS movement. Without him, there is no movement. Like him or not, don't forget it.

  47. Re:Report roasts Linux (it's only Meta Group) by Tim+Colgate · · Score: 1
    Are any of those things true? What does that say about the rest of the article?

    I've noticed that whenever Meta group report on Linux they always denigrate it. There have been articles on ZDNET and similar places where positive things have been said by Gartner, IDC etc., but then at the end there are some words of doom from Meta Group: "it may not be ready", "there might be problems", "you can't yet run Linux on 1000 processor machines...".

    For example, look at this article about Linux in investment banks. Positive news all the way through until:

    But Meta Group programme director Ashim Pal says the cost of the platform is not the only consideration. 'The operating system is a relatively small part of the total cost of ownership. Purely focusing on the cost of the platform is deluded,' he said.

    If you go their web-site and look for recent documents featuring Linux in the title you will find:

    - Linux on the Mainframe: Nice Place to Visit, But...
    - No Advantage From Linux PDAs
    - Choose Palm or Pocket PC - Linux Only for Custom Apps
    - Linux PDAs Offer Alternative for Low-End and Specialized Markets
    - Companies Should Consider Limited Server-Based Linux Implementations
    - Microsoft Criticizes Linux as Operating System Issues Move to Web Services Level
    - ... Linux Management: More Hype than Substance
    - Linux Dreams of Management Promotion.,
    - Linux: Application Server Tiers or Tears?

    I guess you can make your own minds up. BTW, Meta Group have been having a few problems themselves recently.

  48. Re:How about something relevant? by Anonymous Coward · · Score: 0

    I'd have to say the Civil Rights movement completed many of the objectives of the New Deal, and not so much of reconstruction. For more info, read a GODDAMN HISTORY BOOK!

  49. IBM VM by theolein · · Score: 2

    First I must say that my story is a long time ago (like the author of the article). I was an operator on an IBM 3083 17 years ago and left a few months after they had installed VM. We had the mainframe connected to the comanies bottlings plants across the whole country (running system 36 minis) and during the day, especially later in the afternoon most of the various plant's accounts/processing data would come in. The night shift would then start the accounting and processing jobs around 7PM and run them through the night and a few hours before the morning shift came in the Storage backup system would run (HSM) and then during the day the coders would do their thing etc.

    The whole point of VM (and the mainframe) was that it is optimised for business systems, AFAIK, and unlike heavy scientific computing loads, there is seldom a need for incredible processing power in the CPU, but there is a need for distributed processes and extremely good I/O since most business tasks are often thrashing around on the disk getting and updating customer/financial info etc.

    I don't think the zSeries would be doing as well as it is (eBay, Swedish and Japanese telcos etc) if there wasn't some advantage to this system. Probably, what sways a lot of these deals is that if your machine has any problems IBM will have a technician there pronto and their staff (at least in those days) were very professional and well trained.

  50. Performance by Anonymous Coward · · Score: 0

    I didn't get the part of the article about swapping to a RAM disk. That doesn't really make a lot of sense.

    But, for what its worth, I have used Linux on an S/390 for software development. I found it performed just fine as an interactive environment and no different than any other multi-user system.

    Sure, sometimes you notice a slowdown under heavy load, but it was very rare and short-lived.

    As for application portability it seemed to have no problem with ANSI C code and POSIX functionality. It's Linux, as long as your code doesn't do nutty things that are not guaranteed by ANSI, Linux/390 functions just like a large Sun or HP machine with lots of people compiling and editing.

  51. Linux vs TPF by spacefight · · Score: 1

    hm. the article on lw.com states that sendmail can handle about 2 million boxes on an IBM Mainframe. Well, according to this article at ibm.com, a Mainframe of the same architecture can handle 250+ Million of Users (IMAP, POP3 and SMTP). Guess Linux can step back in this specific case against the not really well known TPF Operating System (currently used at the IT Farms of Airlines and large Banks).

  52. Linux is dying by Anonymous Coward · · Score: 0

    Linux just doesn't work as well as FreeBSD. IBM would be better off supporting FreeBSD.

  53. Re:Linux has scalibility problems (run FreeBSD) by Anonymous Coward · · Score: 0

    FreeBSD scales way better and is more stable than *linux. Spread the word. We need to let people know there's something better out there.

  54. Pretty good! by doorbot.com · · Score: 1

    That was quite a few keywords there. Definitely a varied combination. If they'd been assembled a bit better, your post might have made sense! Next time, link each word to E2 for added mod points.

    Keywords:
    Linux, GNU, mainframe, NT, OpenBSD, USB, multithreading, kernel

    There were others, but you get the idea. Now, which ones don't belong?

    At least NT, OpenBSD, and USB. Of course, those are the majority of your argument (and the rest of your post was simply unrelated fluff).

    Yours was definitely a Slashdot post for the ages.

  55. Re:Holy fuck Voyager sucked last night by Anonymous Coward · · Score: 0

    Hell. Yes.

  56. FreeBSD also has COW by Anonymous Coward · · Score: 0

    FreeBSD also has COW and is more stable and faster than Linux. IBM should switch to FreeBSD because FreeBSD is truly free.

  57. Re:Linux Sucks! by Anonymous Coward · · Score: 0

    Please do not do that! FreeBSD is already available to run on your PC and it is truly free source, with even the installer included, which most proprietary *linux distros will not give you source code for. FreeBSD is more stable and faster than linux and more advanced too. It embodies decades of Unix(tm) research that Linux keeps reinventing due to NIH. Please put a stop to this madness and start spreading the word about FreeBSD.

  58. Re:Alpha? A beautiful piece of work by Anonymous Coward · · Score: 0

    Alpha was a 64-bit chip in 1992. DEC sued Intel over the contents of the Alpha, and Intel paid them a large sum of money in settlement. Then, DEC sold itself (what was left) to Compaq. HP is planning on dropping Tru64, don't know if it's planning on dropping the Alpha. Hope not -- it's a beautiful design and only gotten better over the years. It's a shame IBM didn't buy the Alpha. Also a shame that DEC never knew how to sell.

  59. Heh by Anonymous Coward · · Score: 0

    Mainframe UNIX is an oxymoron.

  60. i'm Running a Linux/S390 Solution by Anonymous Coward · · Score: 0

    Linux and s390 isnt a swiss arm knife, if you want raw cpu process go to RISC.
    IBM line.
    Xseries, INTEL.
    PSeries, RS/6000 P=PERFORMANCE
    ISeries, AS/400 I=Integration
    ZSeries, S390/Zseries Zero Stop.

    The Mainframe advantage is handle large amount of data, impressive IO access and uncomparable stability.

  61. What have you done! by jsse · · Score: 2

    "Thank you for your interest. We are performing system maintenance at this time. LinuxWorld will return shortly."

  62. We're implementing it by cat_jesus · · Score: 1

    I've pushed hard to have Linux put on my client's mainframe. The mainframe has superior storage management and security so it's the best place to keep massive amounts of data(massive to the PC mindset). My client has a need to have certain reports available forever and the reports in question are about 40 gig in size for the first year. This has been expected to grow quite a bit in the next few years to something like 100 to 200 Gig a year. Since the reports for the most part will not be accessed often, it makes no sense to build an NT box just to serve up these reports when they're requested(a Linux box on a server machine is out of the question in this shop--politics).

    The users will request their report on the Linux ghost box and the Linux system will request the file from MVS which likely will reside on cart, I mean tape. The tape subsystems are extremely fast and the hardware is already budgeted and in use. The NT folks wanted all sorts of money for a new server, OS, etc.. it just wasn't worth it.

    The hardest part is selling the idea, I mentioned it to the manager I report to and he said, "What's Linux?" I'm not kidding. This IT manager had never even heard of Linux. I found that the best way to make sure it happened was to go ahead and just make a prototype. Systems programming on the mainframe side were enthusiastic about loading it and got it going in short order(they want to screw the NT people anyway). It not only works but retrieval from archive is seamless and quick. Security is easy to handle because the users are already defined in RACF with certain rights, we just need to add those datasets to their IDs. After we're done there should be no more manual intervention(which supposedly was needed with the NT solution)

    Other groups at the client site are now aware of what we are doing and would like to publish their own reports on the intranet from the mainframe without having to go through the hassle of dealing with the NT groups. Since departments in this company are not charged for their mainframe usage but are charged for any NT servers they need, it's a no brainer for management-- once you show them it works. You often have to lead these people by the hand. You also need to engage systems programming. Those guys have all sorts of neat soultions to problem but they are terrible when it comes to marketing their solutions.

  63. Wrong... stupidity or by intent? by Anonymous Coward · · Score: 0

    Of course Linux TCP/IP is multithreaded.
    This is why the 2.4.0 kernel took so
    long to release.

    Of course Linux TCP/IP can pass multiple
    packets at the same time. This has been
    the case from day one, before the 1.0.x
    kernel was even released.

    Linux beats Slowaris up to at least 8 CPUs,
    and completely roasts Slowaris on 1 CPU.

  64. Re:Alpha? A beautiful piece of work by old_fortran · · Score: 1
    Both HP and whatever Unix group remains at Compaq (the remenants of the DEC Alpha team) will continue to sell RISC for at least 2 more years (and probably longer). The Roadmap on the "new HP" site showed continued use of the PA-RISC as well as EV7 and EV79 for the Alphas, so this is roughly through 2004. I would bet that until the Itanium Family CPU's significantly exceed either RISC CPU family in terms of price/performance, we will still see the older CPUs continue.

    The earlier poster made the mistake of confusing NT itself with applications on NT. NT itself was a native compile for the Alpha (as it had been earlier for PowerPC until that CPU also was deemed to be unusable/unsellable for NT). Of course, this created a problem, because almost nobody created native Alpha binary versions of their applications. So DEC had a OS "smart" emulator that worked as was described (e.g., more you used it the better the speed). But this emulator was used for i86 binaries running on Alpha, not for native code.

    One of the avantages of NT Alpha was it was a cheaper box than Unix Alpha (or at least it was when I still worked for DEC). Still, it was always more expensive than the comparable x86 32-bit boxes. Still, if Microsoft had produced NT 5 in 1998 as planned in both 32- and 64-bit versions, then the Alpha would have been the only platform besides IA-64 that would have been available, but 4 years later this is all just old news (and getting more useless every day, except for the "learn by example" of what not to do if you want your Tech company to continue living).

    Regarding the suit between DEC and Intel, my money was on Intel having "borrowed" IP from the Alpha team, especially the wetware they hired away from DEC to learn how to build high-speed silicon. At any rate, I don't believe Intel paid for the suit, but for the Alpha FAB in Hudson Ma., which would still have been worth some $$$ prior DEC to getting sold to Compaq. This freed DEC of some debt, as well as having the cloud of the underlying lawsuit eliminated prior to the buyout.

    Given "The Register" comments a few weeks back about even 2nd Gen IPF CPU's merely being almost equal to current RISC CPU's because the complier engineers are still trying to figure out how to build EPIC-savvy compilers, I'd say we still have a ways to go before we see the IPF CPU's killing off the other CPUs. Remember, Compaq declared Alpha "Dead" just before the HP merger announcement, just like DEC sold off the Alpha FAB just before the Compaq merger announcement. Lots of this just seems to be business, not technical.

    Intel has the megabucks needed to continue building FABs; neither HP or Compaq do, and certainly not now after the merger. Both went "fabless" just like SUN, and for the same reason. This ties them to the IA-64 EPIC architecture in a "bet-the-company" fashion, so it is also no surprise that Compaq sent some of its best Alpha Compiler people over to Intel as part of the Alpha death announcment; Intel needs good 64-bit Compiler designers, and the Alpha team was some of the best around.

    And for all those reading this and thinking - "Why should I care about the Alpha?" just remember. Alpha CPUs used to win benchmarks by wide margins once upon a time, especially floating point ones. And this was at a time when all the other CPUs were still 32-bit (1993-1994 - except MIPS), so they had an advantage over Alpha - no extra overhead from doing everything in 64-bit mode. So the Alpha's won even though they were "handicapped" by the 64-bit overhead, at least until DEC sold the fab, and Compaq took over. Just go back and look up the benchmark results - Alphas stayed at the top or at least competitive until their speed stopped rising, because of lack of investment.

    So all you SUN lovers out there - keep your eye on the "Solaris on IA-64" story; if HP/Q get the IPF CPUs competitive (with appropriate compilers of course), they will have a significant price advantage over SPARC. IBM of course owns its own fabs, and had "built-in" market share for the z-Series (Mainframe) and i-Series (AS/400) boxen, so it can still make high-end RISC CPUs. I just wonder how SUN will be able to continue with SPARC past this next generation coming.

    Of course, your mileage may vary ...

    **AC**

  65. Re:Alpha? A beautiful piece of work by Anonymous Coward · · Score: 0

    Well yes, the alpha put up good benchmark numbers, but it also ran about 5X the speed of the competition. I think that the numbers have sess to do with compilers and more to do with fabs.

  66. Re:Linux has scalibility problems (run FreeBSD) by Anonymous Coward · · Score: 0

    Yea apple jelly is better than grape jelly, but there is no need to spread the word; there is not enough difference.

  67. Where is the article? by ehiris · · Score: 2

    If you still have the article somewhere can you please post a link to it?

    Thank you