yring

Bounded SPSC ring buffer with ypipe-style batched flush/prefetch.

Algorithm

Three pointers instead of two:

• head: consumer read position (AtomicUsize, consumer-owned)
• tail: producer write position (plain usize, producer-private, no atomic)
• flush: last flushed position (AtomicUsize, producer writes / consumer reads)

push: zero atomics. flush: one Release store. pop: zero atomics. prefetch: one Acquire load. Result: one atomic per batch on each side.

This is the core ypipe innovation from ZeroMQ, applied to a fixed-capacity ring buffer instead of a linked list.

Performance

760M items/s between threads (u64-sized values, batch of 256, capacity 1024). Batching amortizes synchronization cost to near zero under load. Run cargo bench -p yring to reproduce.

Usage

let (mut producer, mut consumer) = yring::spsc(1024);

// Producer side: push with zero atomics, flush once per batch
for i in 0..100 {
    producer.push(i).unwrap();
}
producer.flush(); // one Release store makes all 100 items visible

// Consumer side: prefetch with one Acquire load, pop with zero atomics
consumer.prefetch(); // one Acquire load
while let Some(val) = consumer.pop() {
    // process val
}

License

ISC