> I know about pg_dumpall, which creates a humongous SQL file, but is
> there something equivalent in the postgresql world, like a
> "pgsqlhotcopy" which copies data folders in a similar way as
> mysqlhotcopy?
If you're lucky enough to be using a filesystem which supports atomic
snapshotting of directories (LVM and ZFS, I believe), you could just take
a snapshot of your entire Postgres data directory. See e.g.
http://lethargy.org/~jesus/archives/92-PostgreSQL-warm-standby-on-ZFS-crack.html
Note that mysqlhotcopy essentially works by forcibly locking all tables while
the copy is going on -- for any moderately big and busy server, this is a
huge problem.