go-spscqueue

This repository contains a type generic single-producer single-consumer bounded queue go package. The implementation is based on go's generic capabilities introduced in go version 1.18.

The algorithm is similar to the C++ implementation described here (and available here). It is lock-free and tries to be cache-friendly.

Usage

q := spscqueue.New[int](16)

// The producer may call these functions:
q.Push(1)        // Add 1 to the back of the queue.
ok := q.Offer(2) // Try to add 2 to the back of the queue.
fmt.Println(q.Len())

// The consumer may call these:
v := q.Pop()        // Retrieve and remove the item at the front of the queue.
v2, ok := q.Front() // Try to retrieve the item at the front of the queue.
if ok {
	q.Advance() // Remove the item at the front of the queue.
}
fmt.Println(q.Len())

// There is also a Reserve-Commit pattern, which allows the producer to access
// the underlying queue data. This is potentially useful when working on
// pre-allocated data.
v3, ok := q.Reserve() // Work on the underlying queue data.
for !ok {
	runtime.Gosched()
	v3, ok = q.Reserve()
}
// Do something with v3.
// ...
q.Commit() // Present the element to the consumer.

The combination of Front() and Advance() achieves the same as Pop(). Using them allows for more fine grained control as to when the particular queue slot is marked as available for re-use by the producer.

Installation

go get github.com/fjbotha/go-spscqueue/spscqueue