Myths Programmers Believe about CPU Caches (2018)
If cache coherence is relevant to you, I strongly recommend the book “A Primer on Memory Consistency and Cache Coherence”. It’s much easier to understand the details of coherency from a broader perspective, than an incremental read-a-bunch-of-blogs perspective.I found that book very readable, and it cleared up most misconceptions I had. It also teaches a universal vocabulary for discussing coherency/consistency, which is useful for conveying the nuances of the topic.Cache coherence is not super relevant to most programmers though. Every language provides an abstraction on top of caches, and nearly every language uses the “data race free -> sequentially consistent”. Having an understanding of data races and sequential consistency is much more important than understanding caching: the compiler/runtime has more freedom to mess with your code than your CPU (unless you are on something like the DEC Alpha, which you probably aren't).If you are writing an OS/Hypervisor/Compiler (or any other situation where you touch asm), cache coherence is a subject you probably need a solid grasp of.