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Comment by shmerl | Hacker News Reader

I'm impressed too, if only it wouldn't have those nasty mce and segfault bugs, and AMD could actually explain what's going on after all this time testing it.

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I don't know why you are being downvoted (I am no expert), but it seems like the segfaults are a big deal.

AFAIK it's currently being blamed on a bug in the PHP testsuite that segfsults in Intel too.

Segfaults happen under heavy compilation workload - nothing to do with PHP specifically, for instance compiling Mesa produces it. And mce bug means random freezes and reboots, when CPU core wakes up from some sleep C state.

I'm still quite certain that some test suite had a faulty PHP benchmark that segfaulted on both vendors and people claimed it was Ryzen only.

Oh well.

Either way, IMO it's not a roadblock for office and gaming usage.

It is a roadblock, if you need to build something from source and it segfaults. Can be quite useful for gaming too (building Mesa, Wine, open engines and what not).

Besides, mce bug is more critical, since it actually makes the whole system unstable.

The MCE bug might explain some behaviour on my system, however, I could just as easily also blame frequent brownouts.

On the other hand, the compile thingy has never been an issue yet, despite me compiling a lot of things. (Ryzen 7)

And for gaming, I've never had a game crash, I do doubt that many people really game under Linux yet, most gaming happens on Windows.

Office use is not roadblocked at all.

These bugs aren't consistent, and likely affect only part of Ryzen CPUs of the same model, not all of them. That's why the results are so over the place for different people. It also can be affected by power setup, which adds a lot of variables and makes it harder to reproduce.

By the way, for users or Gentoo or other distros which actually build packages when installing them, these segfaults are a very major roadblock for any kind of use case.

You're right about that. The context there was another phoronix article. https://www.phoronix.com/scan.php?page=article&item=ryzen-se... and the update to it explains what happened.

There are however reports of segfaults during compilations that seem more Ryzen-specific, though even there GCC versions were said to play a role. It is all a bit obscure currently.

The last story on 'AMD segfaults' actually segfaulted on Intel processors too.

You can make a test that will segfault everywhere. We aren't talking about those, but about regular workloads, like compiling Mesa for example. If Mesa compilation segfaults everywhere, something is really wrong.

The early examples were supposedly going to be fixed with a microcode update. What happened with that?

There were no microcode updates that fixed this issue so far.

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