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Shared mutable state in Rust (2022)

by vinhnx on 4/1/2026, 11:33:41 PM

https://draft.ryhl.io/blog/shared-mutable-state/

Comments

by: the__alchemist

I think which tools you use for concurrency depends on your code style and what you&#x27;re doing. For example, I haven&#x27;t reached for Arc in a while. Example of the two primary ways I&#x27;ve been doing it:<p>Embedded: Mutex + critical sections + hardware interrupts. The Mutex isn&#x27;t std::Mutex, but a hardware-specific one. (E.g. ARM) works in a similar way. The default syntax is a mess of RefCell, Cell, Option, with the requisite &lt; and &gt; characters. (The Option is so you can insert a value in on init, then it&#x27;s never None) etc. I work around this with macros.<p>PC applications (GUI, 3D etc): std::thread and MPSC receivers&#x2F;transmitters which update a state struct when they&#x27;re ready. Then poll in the GUI&#x27;s event loop or w&#x2F;e. I believe this workflow has worked for me in lieu of Arc because I have been structuring programs with a single main thread, then sub threads which perform non-blocking tasks, then return data to the main thread.<p>Also: If it&#x27;s a primitive type, Atomics are nice.

4/5/2026, 3:21:58 PM


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4/5/2026, 2:41:45 PM


by: FpUser

I have shared mutable state which is available through the whole application lifetime. Having ARC in this situation makes no sense, single mutex should be all I need.

4/5/2026, 12:44:16 PM