BUG #8115: Increased session memory usage after pg_upgrade

The following bug has been logged on the website:

Bug reference: 8115
Logged by: Daniel Cristian Cruz
Email address: danielcristian(at)gmail(dot)com
PostgreSQL version: 9.2.4
Operating system: CentOS release 5.5, Linux 2.6.18-194.32.1.el5 #1 S
Description:

I had a server with PostgreSQL 9.1.4 which I tried to upgrade to 9.2.4 with
pg_upgrade.

After the upgrade I got a working server where some queries were using more
memory than old version.

Details in thread:

http://www.postgresql.org/message-id/CACffM9F-aSTopQ3G0mZvyWusp=RPZ=MmnPn26MKVtDb5r-JaDw@mail.gmail.com