C++ Details of Asymmetric Fences
48 points by anon_farmer 5 days ago | 4 comments

ot 3 hours ago
This is a great article but it goes into a lot of detail that can be intimidating at first.

For me, the reading that made asymmetric fences "click" is this: https://pvk.ca/Blog/2019/01/09/preemption-is-gc-for-memory-r...

It might be easier to read that first, as it also goes into practical applications, and then this one.

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fschutze 27 minutes ago
Thanks, this is very useful. Reading it I was wondering how applications typically exploit the asymmetric fence, I hope the article you linked help in that regard.
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KenoFischer 52 minutes ago
I also just added these to Julia for 1.14 (https://github.com/JuliaLang/julia/pull/60311).
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jeffbee 3 hours ago
I can't help myself digging into the referenced source code. The membarrier syscall can fail to allocate, returning ENOMEM. The way Folly calls it, the program would abort. Which I guess is a fair strategy but it's good to know when your synchronization primitive is actually SynchronizeOrCrash.
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nttylock 5 hours ago
[flagged]
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