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A comment on Examining ARM vs. x86 Memory Models with Rust. Parent comment

Re:Examining ARM vs. x86 Memory Models with Rust by Someone on Saturday June 27, 2020 @04:01AM (#23660254)
Old software will have been tested on CPUs with weaker memory models.

Also, Multi-threaded programming is hard, so the really long tail probably already is buggy on x86. Surfacing their bugs more often may be a blessing in disguise.

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Re:Examining ARM vs. x86 Memory Models with Rust by zozbot234 on Saturday June 27, 2020 @05:53AM (#23660709)
In practice, CPU's with weaker memory models tend to be newer - a single-threaded CPU being the strongest model of them all. There are some interesting exceptions, such as e.g. the Alpha architecture - which is so 'weak' it needs a memory barrier even on pointer/array indirections, if multiple threads might be involved! (I actually did some digging and explained the issue in https://news.ycombinator.com/item?id=22282049 this old thread.)
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Re:Examining ARM vs. x86 Memory Models with Rust by gpderetta on Saturday June 27, 2020 @07:23AM (#23661101)
ARM, POWER, early SPARCs all have a weaker memory model than intel.

It is true though that with near total x86 domination i the server market for the las 20 years, newer server software might have a lot of x86-isms.

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