421 points bcantrill | 1 comments | 31 Oct 25 16:49 UTC | HN request time: 0.237s | source
This RFD describes our distillation of a really gnarly issue that we hit in the Oxide control plane.[0] Not unlike our discovery of the async cancellation issue[1][2][3], this is larger than the issue itself -- and worse, the program that hits futurelock is correct from the programmer's point of view. Fortunately, the surface area here is smaller than that of async cancellation and the conditions required to hit it can be relatively easily mitigated. Still, this is a pretty deep issue -- and something that took some very seasoned Rust hands quite a while to find.
yes, you can produce similar issues with promise guarded states and so on as well, it's a fairly common issue in async programming, but can be surprising when it's hidden by layers of abstraction / far up/down a call-chain.