[GENERAL] pg_upgrade link mode

[Fabio Rueda Carrascosa]

Hello, I have a 9.1 cluster with 50 databases, only one table per db with
2000 rows only, but a lot of schema around each one (postgis databases)

The old cluster size is 1GB

du -chs /var/lib/postgresql/9.1/main/
1.1G

now I run a pg_upgrade to 9.2 with hard link mode,

pg_upgrade  --link \
    --old-datadir=/var/lib/postgresql/9.1/main \
    --new-datadir=/var/lib/postgresql/9.2/main \
    --old-bindir=/usr/lib/postgresql/9.1/bin \
    --new-bindir=/usr/lib/postgresql/9.2/bin

du -chs /var/lib/postgresql/9.2/main/
880M


Is the expected behaviour? I can't double the space in production.

Thanks.