Identifying your CPU and thread count

[ark.intel.com]

At this point you'll need to know how many threads your CPU is capable of in order to know what number to put in. If you don't already know, you'll need to find out with a bit of Googling. Open 'My Computer' and look at the Computer properties, it should tell you the name of your CPU. For example, mine is an Intel i7-8700K Search your CPU make in Google and you'll most likely get the manufacturers website come up as one of the top results. You can use that to find the exact specs for your CPU. So for example, a search of my CPU tells me it has 12 threads.That means in theory the highest number I can enter in my compiler is 12, which will make it use all 12. This would make it use 100% of my CPU which is the exact issue we're working to avoid, so I would suggest entering a value that is 50-75% of your max thread count. If your CPU has only 4 threads, you'll only want to use 2 or 3. If you have 24 threads, you might want to use 20 of them. I personally set mine to 10 out of 12 (83%)