Thread: BUG #13492: drop database does not release disk space

The following bug has been logged on the website:

Bug reference:      13492
Logged by:          Ismael Bezerra
Email address:      ismaelbezerra@gmail.com
PostgreSQL version: 9.4.4
Operating system:   Linux CentOS 6
Description:

I'm having problem to drop a database. When performing the drop database
command postgresql does not release the disk space. The directory with oid
database remains on disk. This database has been updated from version 9.3.4
to 9.4.4 with the -k option pg_upgrade. What can it be?

ismaelbezerra@gmail.com writes:
> I'm having problem to drop a database. When performing the drop database
> command postgresql does not release the disk space. The directory with oid
> database remains on disk. This database has been updated from version 9.3.4
> to 9.4.4 with the -k option pg_upgrade. What can it be?

If you forgot to rm -rf the 9.3 database directory after you were finished
upgrading, then all those files are still hard-linked into the 9.3 tree,
so they wouldn't disappear after being dropped from the 9.4 tree.

            regards, tom lane