Checking active sessions

Using this recipe, we will get all the active sessions from a PostgreSQL instance, which are utilizing the server resources.

Getting ready

Like other database management systems, PostgreSQL is also providing a set of catalog tables and views, which will help us to retrieve the current instance status. In this recipe, we will be discussing a catalog view, which every DBA/developer queries very frequently.

How to do it...

1. Connect to your database using the psql client as a superuser and check the track_activities parameter status:

           postgres=# SHOW track_activities; 
           track_activities 
           ------------------ 
           on 
           (1 row)
   

2. Initiate the pgbench test as follows:

           $ pgbench -i; pgbench -c 4 -T 100 
           creating tables... 
           100000 of 100000 tuples (100%) done (elapsed 0.17 
             s, remaining
             0.00 s) 
           vacuum... 
           set primary keys... 
          ...