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atomic type

A number the hardware can update in one indivisible step, safely from many threads.

std::sync::atomic types (AtomicUsize, AtomicBool...) provide lock-free load, store and read-modify-write operations such as fetch_add, each with a memory ordering.

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Examples

  • Two threads each calling scanned.fetch_add(1, Ordering::Relaxed) 1,000 times on one AtomicUsize always end at 2,000, with no lock.

See also

memory ordering mutex data race
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