How to fix memory leak in ubuntu?

Question

ubuntu

Good evening, on the server there are:
Two sites and a database of 1b and 500 mb,
RAM is full of 2/2 GB, online is usually 20-40 people on each of them + mariadb does not start.

Answer 1

command output

free-m

show please.

Answer 2

Spread into different containers so as not to steal each other's memory. To the greatest extent this applies to the database.