as in the object of the discussion thread I have the following situation: all time I start my linux OS, I check processes running with the top command in bash and I always find 7-8 postgres processes running. Why so? Are they daemon that start at the OS start? Should I deactivate them for better resource usage? And in which way can I stop definitevely them? And how can I reactivate them in future ? Thanks
postgres via upstart:
echo manual | sudo tee /etc/init/postgres.override
Based on this Q/A (shows methods for both systemD and upstart, if you have Ubuntu 14.04 you should have upstart).