Physx Multithreading

This might be a dumb question, but I’ve done a bunch of googling and it sounds like Unity 5 and PhysX 3.3 should support multithreading. However, when I run a project with PhysX and look at Windows Task Manager, the unity process never goes above 16% CPU usage (1 out of 8 cores).

From what I’ve read, it sounds like this should just work automatically, but is this something that needs to be set up manually?

What am I missing?

it’s multithreaded. Switch your profiler to timeline and you’ll see this
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