PgBouncer log management My pgbouncer.log grows endlessly. 

How do I enable filename rollover or limit the logfile size for pgbouncer on Ubuntu?
Until now, pgBouncer doesn't support rotate log. Hence, you have to do it by yourself.

You can refer to sites below:

How to rotate PgBouncer logs in Linux/Windows ?

How To Manage Log Files With Logrotate On Ubuntu 12.10