Answering only the latter question: A Primer on Memory Consistency and Cache Coherence, Second Edition https://www.morganclaypool.com/doi/10.2200/S00962ED2V01

Answering only the latter question: A Primer on Memory Consistency and Cache Coherence, Second Edition https://www.morganclaypool.com/doi/10.2200/S00962ED2V01Y201910CAC049 https://www.morganclaypool.com/doi/10.2200/S00962ED2V01Y2019... (free online book) would help