How to convert Postgres from 32 bit to 64 bit I would like to convert from PG 32 bit to 64 bit. I am testing with pg_upgrade (in several scenarios) but I think it cannot do that. 

With pg_upgrade, I can upgrade PG version 8.5 to v.9 (both of them run in 32 bit or  64 bit).

Until now, I haven't found how to change from a 32 bit install to 64 bit. How can this be done?
You can't use pg_upgrade for this, as it can only upgrade clusters from versions that are built with the same options on the same architecture. You must either:


dump and reload, with the associated down-time; or
Run both the 32-bit and 64-bit versions concurrently and set up a 3rd party replication tool like Bucardo, Londiste or Slony-I to stream rows across. Once they're in sync, stop the 32-bit DB and remove the replication.


Also, there's no PostgreSQL 8.5. Did you mean 8.4? "v9" isn't very specific either - PostgreSQL 9.0, 9.1, and 9.2 are all quite distinct releases. See the version policy, which outlines PostgreSQL's quirky versioning.