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> All users had admin rights and each one thought that they could make their models run faster by bumping up the process priority as far as it could go - which of course interfered with the realtime processes needed to manage the effective running of the computer

It amazes me what the bios and OS or OS api's let you do, even on modern devices.



> It amazes me what the bios and OS or OS api's let you do, even on modern devices.

Same, but not necessarily in a negative way. I like pushing my hardware and software to the limits, becoming unable to push those limits would be pretty disappointing.


I'm not sure anyone should call VMS "modern", but that's beside the point ;)

VMS has a very comprehensive system of quotas and limits, so a "properly" configured system wouldn't suffer those issues.

And furthermore, VMS isn't intended to be used "interactively" as such. You should be submitting work to the built-in batch queues - each with various attributes that can include the priority level. This allows the system to intelligently manage work based on a comprehensive view of the entire system - something a single user in a multi-user system can't have. If you like pushing a multi-user system to its limits, you'd be impressed with what VMS could do even way back in the 1990s.


We don't typically use multi-user systems, actually - I'm pretty sure Logan meant our personal hardware. For example, we run an i5-12400F at 5.2GHz and run a fairly customized Windows 11 Enterprise, both of which would become impossible if our BIOS and operating system were too much more locked down.

I mean, our motherboard has an external clock generator almost entirely dedicated to pointing and laughing at CPUs with a "locked multiplier". (It's also used for PCIe 5.0)

-Emily (see HN profile for details)


We don't typically use multi-user systems, actually

Isn't pretty much every "cloud" nothing more than an elaborate multi-user system?


okay, then we don't own computers that are intended to serve multiple physical users. They may run multi-user operating systems but ours are typically configured with only one actual user*.

*ignoring all the system and service users in OSes like Windows and Linux.

-Emily


> i5-12400F at 5.2GHz

Overclocking. Profile explains why. For security I prefer single cores, but have to work with whats available.


> Overclocking. Profile explains why.

Not sure whether you're referring to your or our profile, but yes, we do overclock to a significant degree. Our motherboard has a setting to downgrade the CPU microcode to an older version that doesn't try to detect higher clock speeds and shut down. Clearly, stuff is already getting more and more locked down even as we enjoy our relative freedom in the present.

-Emily


Running code on a priority thread enables interception of data on a normal priority thread which can then invalidate the data.

Its a problem I'm facing at the moment, trying to keep the data as it moves around the hw, tamper proof.

Intel CPUs are designed with certain characteristics, which can highlight thread priority attacks.

Cant comment on ARM or AMD yet, havent tested them.




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