Everything you always wanted to know about synchronization but were afraid to ask

This paper presents the most exhaustive study of syn-chronization to date. We span multiple layers, from hardware cache-coherence protocols up to high-level concurrent software. We do so on different types of architectures, from single-socket – uniform and non-uniform – to multi-socket – directory and broadcast-based – many-cores. We draw a set of observations that, roughly speaking, imply that scalability of synchroniza-tion is mainly a property of the hardware.