Bulldozer00's Blog

In the beginning of Robert Virding’s brilliant InfoQ talk on Erlang, he distinguishes between parallelism and concurrency. Parallelism is “physical“, having to do with the static  number of cores and processors in a system. Concurrency is “abstract“, having to do with the number of dynamic application processes and threads running in the system. To relate the physical with the abstract, I felt compelled to draw this physical-multi-core, physical-multi-node, abstract-multi-process, abstract-multi-thread diagram:

It’s not much different than the pic in this four year old post: PTCPN. It’s simply a less detailed, alternative point of view.