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We had a pair of VAX 785s (I think - my memory of the last millenium occasionally fails me) and were running real-time flight telemetry and analysis on them. So cool and, since we very close to the runway, very noisy! Jet fighters on reheat make a LOT of noise on take-off.
- I would love to change the world, but they won’t give me the source code.
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Maybe there were good uVax implementations. But the first attempt to build a small Vax was the 730. From a performance point of view, it was a nightmare!
Friends of mine were using it and reported that had timed the filling an 80 char input buffer with spaces to take 20 milliseconds. A process switch took 100 ms - 1/10 second(!). In their project, they had to change the software architecture from three to two processes (and redistribute the functions) in order to reduce the required number of process switches; that significantly increased the performance of their application. It took just a few weeks before someone got hold of a big yellow-green "Turtle Wax" sticker to put on the front panel of the machine.
The 730 was an extremely microcoded machine, with a highly vertical architecture: While the 780 had a 96 bit microcode word, so that it could issue 96 signals per microcycle, the 730 had 24 bits, heavily multiplexed. So the meaning of one bit could depend a lot on other bits, and had to be decoded by a logic network before sent to the actual circuits. The hardware itself was also far simpler, so it took a lot more microcycles to perform one complete machine instruction.
Even the 780 had some hardware limitations, the strictest one (for the performance) was that all page tables had to be resident in memory; it couldn't handle a page fault in the page fault interrupt handler. In 1970 or 80, our university had one 780 with a whooping 1 megabyte of RAM. Whenever the electronics guys ran their circuit layout program, which used immense amounts of virtual memory, they had to reboot the machine with a large page table configuration so that more than 600K was taken by the page tables and resident part of the OS, slightly more than 300 kbyte was available for paging of user programs and non-resident OS parts. You may call it "CPU abuse" to run a VAX 780 CPU on 1 megabyte of RAM, but if you weren't there at the time, you would never believe the cost of RAM in those days...
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The proper plural form is "vaxen". That was a commonly used terms in those days.
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So can I get an example of a "proper" operating system then?
OTOH, "proper" sounds like something that would be in conflict based on needs.
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Can't you just download the code and fix it ?
I'd rather be phishing!
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That argument again. Nobody seems to want to own it.
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I guess they figured if you were coming from a Unix/Linux background that's the way it's always been and you should know what to expect. But if you're coming from windows you need all the help you can get...you know the GUI thing and all!
I'm currently unsupervised, I know it freaks me out too!
JaxCoder.com
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I've never heard of a hardcore Linux guy who ever wanted to make anything easier for the Windows crowd. Remember that Linux has been described as "user-friendly, but it gets to choose its friends".
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The big kids put themselves in the sudoers group. 
Edit: then they type "sudo init 0" (shorter)
If you can keep your head while those about you are losing theirs, perhaps you don't understand the situation.
modified 10-Mar-19 16:41pm.
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theoldfool wrote: Edit: then they type "sudo init 0" (shorter)
No, we login as root and type halt. Dang lusers shouldn't be on my machine, anyway. 
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Seems a bit pointless, to me.
I mean, why on Earth would anyone ever want to shut down a computer?
I wanna be a eunuchs developer! Pass me a bread knife!
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Two words: Memory leaks.
The MicroVAX 3600 I managed while in college would crash on Tuesday unless I had rebooted it on Friday.
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Hmm... when I worked at DEC, the uVAX II under my desk ran for months on end without a reboot. And when I did reboot it, it was to install an OS or tool upgrade.
/ravi
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Indeed. And later I worked with AlphaServer systems that ran for years without even needing to have our product restarted.
I fear the college was running some sub-par third-party software.
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Side tracking a little:
Raymond Chen, in his delightful book "The old new thing" (based on his equally delightful blog of the same name, [^]) he tells about this web server that just had to be available 24/7, but some memory leak made it crash every now and then, every few days. To keep the service running while they debugged the software, they replaced the server with a small cluster and a load balancer: Whenever one of the machines were reaching memory saturation, it was taken out of the cluster and rebooted. In the meantime, the other machine served the users. Later, the other cluster node would be the one to be taken out and rebooted while the first served the customers.
They did find the memory leak, and the installation could go back to single server operation. (There was no need to run a cluster for performance reasons.)
Thumbs up for "The old new thing", both book and blog! The book is fun, but you can actually learn a whole lot from it, especially about legacy and backwards compatibility. (And especially if you just completed your degree and have very limited experience in the commercial world.)
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Mark_Wallace wrote: I mean, why on Earth would anyone ever want to shut down a computer?
Well, there's that. 
I play a lot with different Linux distributions--way, way more than will work with my Linux VM host's 32GB of RAM.
I have another host with 64GB, but that one's for my Windows VMs only.
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I suspect if you run the UI remotely it will prompt for a password....
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I'll have to try. I tend to run my Linux VMs right from the Hyper-V console when RDPed into the Hyper-V host itself; in that context, VMs (Windows and Linux) tend to see that as local, not remote.
I'll have to try with VNC or some equivalent. I hardly ever take the time to configure my Linux VMs to let me log in that way.
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that's from the console - it's then assumed that it's either a single user machine or locked up in a server room - so that user accessing the command should have a clue or two what they're choosing to do.
running the gui remotely normally* doesn't allow root operations (* - of course there are hoops that if correctly arranged and jumped through that can change)
sudo is only for children and below* (* - people that really should just stay on windows)
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lopati: roaming wrote: sudo is only for children and below* (* - people that really should just stay on windows)
What a mixed message. The Linux graybeards all tell you to always run as a limited user and you're a fool if you ever login as root. Or am I misinterpreting your answer here?
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yeah I'm more old fashioned, just start a [x]term, su, do the job, ^D out.
(how many times are there a few instructions to get done? less work for my old fingers doing sudo ..., sudo ..., sudo ...)
but also occasionally I'm on non-linux machine - sudo doesn't always exist
and probably most likely "muscle memory" effect - more used to that way [without thinking too much].
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dandy72 wrote: "Linux is better thought-out than Windows"
You should read "the old new thing" a bit.
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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Isn't that Raymond Cheng's (Chang?) blog? Is he still posting?
I've watched a couple of his "one-minute answer" videos on Channel 9, but I honestly have never taken the time to read his blog.
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dandy72 wrote: Isn't that Raymond Cheng's (Chang?) blog? Is he still posting?
Yup.
The Old New Thing[^]
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
"If you just follow the bacon Eddy, wherever it leads you, then you won't have to think about politics." -- Some Bell.
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My UI always prompts me for a password if I try to do "big stuff". The UI is calling the underlying commands. Your behaviour I never saw. My guess is that you have the passwd saved somewhere in the UI.
"If we don't change direction, we'll end up where we're going"
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