PostgreSQL High Availability Cookbook - Second Edition

How to do it...

Follow these steps to examine the PostgreSQL processes in various ways:

1. In our PostgreSQL connection, execute the following query to find the process ID of the server backend assigned to us:

        SELECT pg_backend_pid() AS pid; 

2. As our root-capable user, attach strace to the preceding pid (4200, for example) with this command:

        sudo strace -p 4200

3. In our PostgreSQL connection, execute the following query to generate some activity:

        SELECT 1; 

4. In the terminal where strace is running, press Ctrl + C to disconnect.
5. Attach strace again, but collect the statistics with the following command:

        strace -c -S calls -p 4200

6. Now, execute the following query to generate some complex activity:

 SELECT * FROM information_schema.columns; ...