5 . Postgres Administration - Background processes 

Background process of postgreSQL and Postmaster process
#list ubuntu home directory
ls /home/ubuntu
#list ubuntu home directory using root permission
sudo ls /home/ubuntu
#Switch to ubuntu user
su - ubuntu
#Add postgres user in sudoer's group
sudo usermod -aG sudo postgres
#Switch back to postgres user
su - postgres
#list ubuntu home directory using root permission
sudo ls /home/ubuntu
#Check postgres background processes
ps -ef|grep postgres
#Kill Auto Vacuum launcher process
kill processid
#Check postgres background processes
ps -ef|grep postgres