What every systems programmer should know about concurrency (2020) [pdf]

Well I learned that the default memory ordering in a std::atomic<> is memory_order_seq_cst. That really surprised me. I had previously imagined that if I'd wanted memory barriers in addition to atomicity, then I'd have to ask for them.

Seems like a strange default to me. Obviously it helps out people who aren't really aware of the problem, but then... surely those people won't think to use an atomic operations library in the first place?

I think the greybeards do, if they have kept up. But these guys aren't around forever, and how do you make sure we keep track of low level stuff, especially with the AI slop entering the marketplace?

I really like this paper, its 12 pages and a really nice piece of work, so good I downloaded it twice!