“Monster Hunter World” game spends 25% of CPU time switching between threads

With 100 threads running like that, not only do you have the overhead of the OS scheduling 100 threads to run on ~8 or whatever cpu cores, but also I would assume these threads are all running different code, so there would be some overhead with context switching / cache. Presumably these threads communicate, so they're likely using some form of synchronization primitives.

Here's a pretty enjoyable video about how they handled this sort of engine design problem using something sensible: https://www.gdcvault.com/play/1022186/Parallelizing-the-Naug...

Intel VTune

Probably because they take 30% of PC gaming revenues.

With no bosses, there’s nobody saying: “no, you have to use this one.”