Draft: Lock-free Ringbuffer Designs

Attaining efficient and portable lock-free containers is challenging as almost any CPU family implements slightly different memory models and atomic read-modify-write operations. C++11 offers a memory model and operation abstractions that enable portable implementations of non-blocking algorithms. In this paper, we present a first scalable and portable lock-free bounded queue supporting multiple readers and multiple writers. Our design uses unique empty values to decouple writing an element from incrementing the tail during enqueue. Dequeue employs a helping scheme that allows for a short common path in the regular case. We evaluate our implementation on a range of architectures featuring weak and strong memory consistency models. Our comparisons with known blocking designs and another novel alternative lock-free design demonstrate that the presented implementation performs well on architectures that implement a weak memory consistency model.