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Sun Bashes Linux on (IBM) Mainframes
dagbrown writes: "An article linked from Sun's front page, entitled
"Linux on the mainframe: Not a good idea" by Shahin Khan, Sun's chief competitive officer, has the interesting theory that Linux on mainframes makes no sense because, among other things, the VM/Linux combo isn't a very good match. What do the folks on Slashdot think?"
Running Linux on a mainframe doesn't change the fact that you must still maintain an expensive, proprietary system, defeating the whole purpose of introducing open standards like Linux.
Running Linux on an IBM mainframe doesn't defeat the entire purpose of using open standards like Linux. You still get the man years of free testing, free software, interoperability, and speed. Or rather, IBM gets them. And by tying software you can't charge for to hardware you can, IBM will have come up with a business model for selling Linux systems for incredible sums of money. Quite an ingenious plan - selling Free Software.
Sun's just pissed they didn't think of it first.
Loneliness is a power that we possess to give or take away forever
And it was a serious pain in the ass. There were problems with the virtual machine suddenly giving up the ghost from underneath us, and we'd see Samba processes go wild for no reason whatsoever. We had load averages spike well into the hundreds, and it was like we were always scrambling to keep it running, as opposed to setting it up and just having it work. We used to tell the students that the machine had caught on fire and had (literally) fallen over. We were even thinking of doing up artwork.
All those impressive demos where they have 32 hojillion instances of linux running on a mainframe are meaningless. Sure, you can do it, but it doesn't do anything. If you try actually working with the setup, you'll be rebooting your machine 10 times a day, and those mothers take forever to freakin' reboot.
For a company that is planning on dropping all support for x86 in the first place, does this really surprise you? as a sun tech myself i totally see there point. Especially when the mainframes they refer to require another proprietary OS to run on top Linux. The article makes some good points, but this is also standard sun marketing.
Sun: A solution looking for a problem
When encryption is outlawed, ou++1!@(93j++js-d9298yIUH(*Y24JKB!~
Just a little FYI:
With Amdahl checking out of the mainframe business it seems IBM has decided to raise mainframe prices significantly - it's actually charged more for the same performance in 2001 than in 2000! This is why IBM's mainframe revenues increased by a fair bit between 2000 and 2001 (while it's PC and Unix revenue dropped). Mainframe revenue accounts for about half of IBM's total server revenue...
I'm not sure what to think about the fact that Sun has a "Chief Competitive Officer." Please tell me that there's more to the guy's job than spreading FUD about the competition.
This article is misrepresented as bashing Linux. It doesn't say that Linux isn't up to the job of running on a mainframe as much as it says that many of the benefits Linux offers are lost when running it on such a system -- basically bashing IBM's solution, not Linux.
Finding mainframe staffing is an obstacle in many organizations(6); combining mainframe and Linux staffing further complicates the matter. Running multiple Linux images still requires administration that needs to grow with the number of images being run.
This statement applies no matter what operating system you choose, you still have to find people who know the hardware. And as with all VM systems, you have to actively administrate each image. This statement is Linux agnostic.
Although z/VM can start and stop Linux images, it cannot dynamically add resources to match demand. As a result, a mainframe would need to size for peak demand just as the Linux farm would; high utilization is a myth.
Again.. Linux isn't repsonsible for the machine not being able to dynamically allocate resources to over-utilized images, it's a hardware/underlying OS issue.
Applications that run on Linux for Intel need to be recompiled and recertified for each new platform; thus the application portfolio to run Linux on a mainframe is small
Duh. It's a different architecture.
So, SUN isn't really bashing Linux, they're bashing their competitor, IBM. No real news here. SUN is very careful not to say "Linux sucks", because they have Linux offerings, they're just saying that customers should buy the SUN/Solaris solution for their high-end systems, not the IBM/Linux solution. I'm sure we'll see something from IBM soon.
--XaXXon
I agree mostly with the article because I recently evaluated an IBM mainframe against an AIX SP2 and a Solaris 4-processor server. Most of the issues in the article, particularly performance, are right on.
The application we were testing was extremely processor and memory intensive. While there was a web component, the biggest problem was moving a large number of bitmaps in one format into the server, convert them from base 64 to a binary representation, rasterize them, and convert them to a "browser friendly" format such as JPEG, GIF, or PNG. We had to complete hundreds (> 200) of these operations per second.
I really wanted to use Linux because most of my staff is familiar with it and our customer felt warm and fuzzy about using IBM equipment. At the end of the day, however, the Linux mainframe only gave us 25% of the minimum speed that we needed for our process to be successful. IBM and a certain German Linux company tweaked everything they could but the performance wasn't there. The AIX vs. Solaris match was more evenly paired. My customer decided on Solaris because they offered a few advantages in Java tools that AIX didn't have. All vendor's boxes had equivalent processor and memory configurations.
I would like to spread the Linux credo as far and wide as possible. What we must understand is that, in order to make Linux a viable option in mission-critical applications (the kind of thing sitting on a mainframe), the performance and "hardening" of something like MVS must be present. Linux just isn't there yet.
Disclaimer: I'm under NDA so that's why some aspects of this posting are a bit vague. Drop me an email if you want more details regarding our experience but our conversation will be "off the record."
Have a nice wknd,
Ehttp://eugeneciurana.com | http://ciurana.eu
Now, Sun offers up the ultimate proof: Linux is just fine as long as it impacts the x86 world - but don't dare put it on a platform that affects us.
To be fair, IBM's offering is not perfect - yet. What Sun is preparing for is a future Linux and Big Iron combo that will be. They are afraid, and this FUD is the proof.
And it was a seriously easy. There were never a problem with the virtual machine suddenly giving up the ghost from underneath us, and we'd never loose a Samba process for any reason whatsoever. We had load averages that were very normal, and it was like we were always scrambling to find new reasons to use it, as opposed to setting it up and just having forgetting about it. We used to tell the students that the machine was seriously hot, and it would never fall-over. We were even thinking of doing up artwork -- AND STARTING A RELIGION!
All those impressive demos where they have 32 hojillion instances of linux running on a mainframe are so meaningfull. Sure, you can do without it, but it will do everything. If you try actually working with the setup, you never have to reboot your machine -- instead of doing it 10 times a day, and those other take forever to freakin' reboot.
But who are you going to believe, ummm, me or ummmmm, that other guy.
Sheesh.
Well then, you should buy a starfire, because you
can keep it running, slap in new processors, new
memory, and then suck them into a running
partition.
It seems that most of the criticisms of Shahin
Kahn's article are based on ignorance. It's a
fair assessment of the liabilities of using
mainframe hardware for typical modern web service
applications. IBM tried to save the mainframe
from declining market share in a very ingenious
way, and Linux and IBM have benefited from it,
but that doesn't mean that it is competetive
with Sun's hardware offerings for the same
application environments.
Not all of Kahn's objections to VMs are valid,
however. The robustness arguments are good, but
the performance ones are short-sighted. While
s/390 Linux may not be tuned today, you can be
confidently assured that it will be soon -- even
if IBM has to fork the kernel to do it.
-I like my women like I like my tea: green-
Sorry, but z/VM has nothing to do with emulation. z/VM is a low-level system that simply (or not so simply ;-) virtualizes the hardware by providing one or more virtual machines, each of which can run any native OS. As far as the client OS knows, it's running on the bare hardware. The z/VM layer provides the ability to flexibly divide the hardware resources between the VMs, and guarantees that each VM is completely isolated from all other VMs. In the case of Linux/390, the Linux kernel and applications have been compiled to run natively on the S/390 architecture. Check out this Linux for S/390 FAQ for more info.
You've got to be kidding me.
The economy and most business models are not a 100% research and development, not-quite-stable environment.
Don't tell a large business "Well, it will get better the more people who use it". They'll spit in your face. They need to know what works, and what works now, and what will continue to work in the future.
Right now, Solaris works. Linux-bigots will sit and say "Well Solaris doesnt provide useful GNU utilities and is a boar when it comes to performance!" Well, yes it is, but it's been around forever, and when Sun says they can make it work, they will MAKE it work. You can't sit around and play with something for awhile in a 100% production environment, and rely on tools which have a sketchy (in a business-model sense) support base. It just cant, and wont, happen.
Just my $0.02.
I have thought hard about whether Linux was a real threat to Sun and whether Sun is a good thing for Linux.
Well, I've come to the realization that Linux is not a threat to Sun. Instead, companies like Dell, HP, Compaq, and IBM are the real competition. What's the catch? They all compete on hardware implementations. They compete on prices and features. Would I still buy a Sun server with Linux? Yes, for the same reasons I prefer Sun servers with Solaris: the hardware has benefits beyond whatever OS happens to be running.
Is Sun good for Linux? Yes, because Sun can provide an absolutely top-notch hardware platform on which to run Linux. All Linux needs are some hardware RAS support features and device drivers, which Sun is probably capable of providing, and better C-compilers for RISC architectures, which could be improvements to GCC or a port of Forte C to Linux.
It is not Sun vs. Linux. I'm convinced of that. Rather, the Linux community should be asking "What can Sun do for us?" rather than "What does Sun have up its sleeve?" These same questions should be applied to all the first-class hardware vendors. The more hardware that Linux runs well on, the better it gets for Linux. It's win-win.
What about Microsoft? Well, that's another war on another front over different principles. Sun is an ally in this war, unambiguously.
Healthcare article at Kuro5hin
...there are other factors than performance, indulge me for a moment:
I work at a big corporation which relied on IBM mainframes for its whole business for almost 30 years until the PC and the high-end Unix servers shook up the landscape for good. I'm from the PC (IT) camp, which has been separate from the Big Iron (DP) guys in the organization since the early days.
DP, once very powerful, has lost a great deal of influence in the 90s, although they still run most of the mission-critical stuff, and the main reason for this were the high-end Unix servers, most of them Sun boxen running Oracle. Believe me, there's no love lost between those two fractions in our company.
Our mainframe guys see Linux as an opportunity to get better integration with the IT world, which was abysmal until now (3270 terminal windows, IMS/DB, TSO/ISPF and such horrors) and to better position themselves against the Sun/Oracle camp which is after their budgets and their butts. Today, we have Linux happily running on our mainframes (still in an experimental phase, not in production), serving up http and Samba shares without a hiccup.
If we're talking about bringing Linux into the large corporations, the crucial influence of IBM cannot be overestimated. We were a died-in-the wool IBM shop (S/390, Token Ring, 3270PC, OS/2, S/36, AS/400, the whole enchilada) and successfully trusted our business to IBM for 30 years (paid through our nose for it, too, I might add). IBM has lots of credibility and trust, so if they say Linux is cool, our CTO listens. Microsoft, on the other hand, is viewed with some "new kid on the block" suspicion. Our management doesn't like downtime and security breaches, and the memory of the ILOVEYOU aftermath is still very vivid, for example. Plus, we migrated to NT4 late (about 28'000 systems, ended September 99) and now Microsoft is practically forcing us into another expensive upgrade cycle sooner than we wanted and with IT budgets cut short on account of the less-than-stellar economy because NT4 support is withdrawn in 2003.
We thus have the following situation: IT and DP are up against the Unix enterprise server guys, all this with the backing of IBM. The astronomically high cost of Sun/Oracle solutions is being questioned more and more, and technologically viable low-end solutions (x86 multiprocessor servers, Linux) begin to rattle the foundations from below.
I don't want to make bold predictions here, but if I were Sun, I'd be worried. To me, it looks like interesting times are ahead.
"There are already a million monkeys on a million typewriters, and Usenet is NOTHING like Shakespeare." - Blair Houghton
Linux on the mainframe can't respond to the workload demands of Web serving with high utilization--something IBM touted at the time of its z800 announcement. Horizontally scaled Linux farms are designed to handle unpredictable demand with above average peak loads. As demand rises, a load balancer distributes the traffic evenly across servers, which increases utilization. Because design capacity needs to handle peak demand, server farms often have a low utilization.
If you have a VM system with two virtual machines, and one of them is nearly idle, and the other virtual machine is very busy, VM will automatically take resources away from the less busy machine and devote it to the more busy machine.
This means that you don't need load-balancing software. VM is the load-balancing software.
Given the relatively low cost of hardware, some organizations find this trade-off acceptable to ensure appropriate service levels. Contrary to what many believe, consolidating a Linux farm into multiple images on a mainframe would not change the demand pattern. Although z/VM can start and stop Linux images, it cannot dynamically add resources to match demand.
Of course it can! The VM kernel will parcel out memory and CPU on demand.
As a result, a mainframe would need to size for peak demand just as the Linux farm would;
All computer systems need to size for peak demand. The difference is that with a mainframe, you can size one machine for the peak demand of the busiest of a large number of virtual machines, and get rid of the overhead caused by the load-balancing software, because you don't need it anymore.
high utilization is a myth.
VM systems can utilize 90-95% of the native computer resources. The overhead on a VM system is very, very small.