How to make TOR work on multiple cores?

Question

linux

In the torrc config it says: (8 core machine)
NumCPUs 4
but TOR works hard on 1 core, eats 100% of the core and in no way wants to run on 4 cores.
I will immediately answer your questions:
1. It is not an option to run how many copies of TOR
2. TOR works in proxy mode so that such a load

Answer 1

At the moment, tor's multithreading is quite limited, a lot is done in the main thread, so in the simplest case it uses only one core. Even on a loaded relay node, it is rare to see that 2 cores are busy.
https://trac.torproject.org/projects/tor/ticket/1749