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A comment on Intel Skylake/Kaby Lake processors: broken hyper-threading. Parent comment

Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by heisenbit on Sunday June 25, 2017 @11:35AM (#14630464)
It may be far better than average software quality but far more also relies on it. The question is whether the quality is adequate in light of what is at stake.
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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by lorenzhs on Sunday June 25, 2017 @11:38AM (#14630484)
Really? How is it different from a kernel bug that causes random behaviour? Both apparently can be fixed with a software update. They're both bad, but why should Intel be held to a higher standard if mitigation is similarly complex?
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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by wav-part on Sunday June 25, 2017 @12:10PM (#14630677)
Because futher down the stack, more reliable a tech has to be. Otherwise good luck debugging. Also agree with heisenbit.
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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by justinclift on Sunday June 25, 2017 @12:32PM (#14630805)
Hmmm... on that note, if the universe is a simulation, then a bug in that could have some interesting ramifications.

"Don't use the bookshelf over there, physics is broken on that shiny spot." :D

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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by krylon on Monday June 26, 2017 @08:07AM (#14636071)
// FIXME Trying to read both the position and the momentum of a particle reliably crashes the simulation.

// Workaround: Make the accessor method return fuzzy values for either of those values.

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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by roywiggins on Sunday June 25, 2017 @01:22PM (#14631070)
The problem with finding a physics bug is that it's liable to be amplifiable. Break conservation laws just a little bit and suddenly you have potential for exponential runaway leading to an unplanned reality excursion, and say goodbye to your light-cone.
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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by justinclift on Sunday June 25, 2017 @01:34PM (#14631129)
Well, by definition the behaviour would be undefined so could go any which way. ;)

Modern day VM software has various levels of exception checking, and code to catch/mitigate/etc when bugs crop up.

So, a universe-capable simulator might have any kind of behaviour if/when a bug occurs. It doesn't need to be an unbounded, runaway scenario. :)

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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by rbanffy on Sunday June 25, 2017 @06:48PM (#14632663)
And, if a very bad reality excursion happens, you scrap that branch and restore the last checkpoint. Nobody inside the simulation will ever remember it. You only bother fixing it if halt/scrap/restore becomes a burden.

It probably happens more often than we imagine ;-)

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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by wolfgke on Monday June 26, 2017 @07:14AM (#14635819)
> Hmmm... on that note, if the universe is a simulation, then a bug in that could have some interesting ramifications.

> "Don't use the bookshelf over there, physics is broken on that shiny spot." :D

You know "The Animatrix - Beyond"?

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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by justinclift on Monday June 26, 2017 @11:55AM (#14637741)
Nope, just looked it up though:

https://en.wikipedia.org/wiki/The_Animatrix#.22Beyond.22

Seems like the same kind of concept. :)

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Re:Intel Skylake/Kaby Lake processors: broken hyper-threading by qubex on Sunday June 25, 2017 @02:01PM (#14631263)
I don't know why you were downvoted. I find this hilarious and thought-provoking.
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