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Don't Nurse Old Hardware - Emulate It
gManZboy writes "Bob Supnik, former team lead for DEC's VAX microprossesor, has an article up on Queue about his Computer History Simulation Project and how emulating old servers may be a better way to keep them running that servicing the physical machines. So how many PDP-11's can you run on a Pentium 4 anyhow?"
Everyone has been so busy emulating the GBA and Xbox that no one has thought about emulating these old servers?
.. but you forget the reason people dont upgrade is that it costs money to do so.
Steal This Sig
Before I even R'd TFA, I thought about one big problem:
How are you going to emulate a 5.25 inch drive to read old disks?
I gave up sigs almost a year ago.
Although this is a very good idea I question the stability of a new emulator vs an old proven system.
By using the original the kinks have already been worked out, quirks are known and understood, and everything just works.
By creating an emulator you have bugs to smash, that's just the way software is. Also keep in mind this seems to apply to big businesses (financial, medical) and large organizations (NASA) with legacy hardware. Since the stability of these systems is absolutely crucial why would they want to switch to a new, unproven, buggy system that stick with the old?
If the DEC VAX systems are so antiquated, wouldn't it make more sense for businesses using these systems to simply upgrade to newer/better technology? I mean even if they have incredibly stability and "wow" factor, wouldn't it be easier than both solutions just to upgrade the software to newer systems. Uptime on many linux/unix systems are just fine for most usage, and QNX has their real time fail proof operating system, but I doubt people using VAX would even need something that powerful.
by Bob Supnik, Sun Microsystems
Gee, I wonder why he would be recommending buying new servers?
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Those who can, do
Those who can't, teach
Those who don't know how, supervise
How do you emulate an 8 inch drive?
Stating on Slashdot that I like cheese since 1997.
You mean emulating a Nintendo or emulation in general? The rights for emulation in general, if its possible to claim intelectual property on something that abstract, should be held by Mr. Turing, since he proved the emulation theorem and demonstrated how to do it, before there even were any computers.
If you keep the old system, it is running at .8mhz, 5mhz, or some other slow speed. It still runs faster emulated, though the emulation is not efficient. It also takes care of problems of repair and replacement of parts.
Fight Spammers!
On a digression, it was great working for Bob Supnick. He's a nice, bright guy and I'm glad to see he's still keeping things stirred up.
In this situation, you could spend a couple of thousand dollars on a new machine and run your old software on it using a free emulator. Hell, the machine you just ordered for your secretary would probably out-perform the old server. The new machine will be one twentieth the size of the old, use one twentieth of the electricity and won't have twenty years of accumulated wear and tear.
If you've got a custom application written in a dead language, emulation may be the best way to continue fulfilling your requirements too. Sure, a new app in the shiny new language du jour might be nice, but if you've got proven 30 year old code and performance on the old hardware is adequate then it makes sense to keep things ticking on a virtual vax or pdp. And think of the kind of server room consolidation you could perform!
Other posters have commented on the proven behaviour of hardware v. emulators - how the latter could have bugs that aren't apparant, and may thus be unsuitable for users like NASA etc. Surely it's easier to produce a bug-for-bug compatible emulator than it is to re-write possibly millions of lines of legacy code in a bug-free manner. Sure, it's nice in the long run to re-write software with greater portability in mind, but while that's happening wouldn't it be worth making sure you can continue to run your existing programs without having to worry what will happen if some obscure I.C. elects a new Pope?
The reason you wouldn't replace the old machines with new stuff is because you lost your source code, or it's in a language no one knows any more, the last guy who understood the system retired 10 yeasr ago, you've been planning for years to shut down this system anyway but you still have a few customers, etc. etc. etc. Unless your old application has decades of life still left in it, it's almost always a better deal to shell out a few grand for a PC + emulator, than to spend tens or hundreds of thousands of dollars rewriting it.
(Warning: Sarcastic or not, this is not a troll. I own a PDP-11/04 that I'm trying to get running, not to mention a bunch of other vintage machines)
Just think of the possibilities! Why try to preserve the Mona Lisa, when we can just photocopy it?
David the statue? Laser scan it, and upload the mesh triangles to sourceforge!
There is nothing that this strategy can't be used on for outrageous savings. We don't even have to manufacture new CPUs at all, just emulate the Pentium5 on your PII!
Emulation is for those that go "Gee, wasn't that nifty", once in their lifetimes. The true enthusiast wants the real thing. If someone restores old cars, they're an auto enthusiast, and people honk their horns at the things on the road, in admiration. If it's home furnishings, they're antique collectors, and magazines do photoshoots of the treasures. But if it's a computer, you were supposed to throw that out after 6 months, to buy another. It makes no sense.
A big one (not the one that funds them) is they are cool.
Useful sometimes. E.g. PDP-11 on a PCI board with a PDP-11 hardware interface is buyable. It's used, among other places, in the postal system to run hardware that needs a PDP-11. Interestingly, it used to use the PDP-11 on a chip but last I checked used an Intel CPU. XEROX had allegedly bought all the remaining PDP-11 on a chip machines for their use in copiers.
The article was pushing the "where we came from" aspects. I KNOW how hard it is to keep PDP-10 hardware running. It's rather handy in defeating patents to come up with prior art...from, say, 1964. The thing here is it's use it or lose it time. You write an emulator and you understand the machine.
Bootstrap Education. A young person can understand a CP/M machine on a level that just isn't going to happen, say, my iBook G4 and use that understanding to bootstrap up to the next level of complexity.