How to limit the number of workerb MongoDB?

In fact, the mongod process is very much paralleled, which is usually good, but in my case, starts to eat all memory and from a large load and sometimes crashes. Need to limit the number of sarkerov (or thread pool, what's he got) to, say, more than 5 is never created and put the rest in turn. Can't find the setting.

And it turns out so much voraciously:

I would like to settle down.