[Day28] Read Rust Atomics and Locks - Introduction of Spin Lock

by Mara Bos

At Topic: Chapter 4. Building Our Own Spin Lock

Recall

Mutex

• Locking a regular mutex will put your thread to sleep when the mutex is already locked.

Notes

We have two locking strategies to ensure that only one thread at a time can access a shared resource: mutex and spin lock

What is spin lock?

Instead of putting the thread to sleep, the thread will continuously attempt to lock the locked lock

When to use spin lock?

If a lock is only ever held for very brief moments and the threads locking it can run in parallel on different processor cores.

• Attempting to lock an already locked mutex will result in busy-looping or spinning

Many real-world implementations of mutexes, including std::sync::Mutex on some platforms, briefly behave like a spin lock before asking the operating system to put a thread to sleep.

References

• Rust Atomics and Locks by Mara Bos
• 並行程式設計
• Code examples of Rust Atomics and Locks.