@PitaJ Thanks. As I have 8 core CPU I want my NodeBB to use all of them. But by default NodeBB is using only one core!
Are you running your reverse proxy, SSL handling, or database on the same box? If so, you definitely don't want all of them for NodeBB.
Even if you aren't, why do you have so many cores, and what are you doing that makes you want to scale like this? How busy is your site? We've topped 191 million hits in a single month on a single core and aren't even working hard.