How to see how much memory a program consumes in linux?

Question

linux

Tell me, is it possible to find out using one command how much memory the program consumes with all its threads. It's not entirely clear to me how to find out.

For example, I'm looking in btop - filtered by firefox. But there are a lot of threads. Is there some kind of tool that will tell you what kind of consumption in general

Answer 1

smem --processfilter="[f]irefox" -t
--processfilter="[f]irefox" - will filter the necessary processes
-t - will display the sum of the filtered

Answer 2

Strictly speaking, no way, given the shared memory and cache. And your btop, by the way, most likely also shows a lie.