Reddit: Octachrons Antwort auf _616_As Frage zum Verhältnis von Threads zu Domains in OCaml
OCaml 4 had a global lock where only one thread could run OCaml code.
OCaml 5 doesn't have a global lock.
However, the unit of parallelism in OCaml 5 are domains. A domain is a set of system-level thread with some runtime data which enable shared memory parallelism. This is in opposition to processes which doesn't share memory (by default) and communicate by sending messages to each other.
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