I need to monitor the DB performance on a distributed system with multiple databases. Some of the database servers use pgbouncer to pool connections and in those servers I can connect to pgbouncer and execute a SHOW STATS; command to retrieve certain statistics, I'm interested in the following:

 avg_req | avg_recv | avg_sent | avg_query
------------------------------------------
     563 |  1080453 |  2060908 |     57718

The columns means:

• avg_req
  Average requests per second in last stat period.
• avg_recv
  Average received (from clients) bytes per second.
• avg_sent
  Average sent (to clients) bytes per second.
• avg_query
  Average query duration in microseconds.

Now my question is, is there a way of gathering this information without using pgbouncer on a postgresql server?