Tom and Nathan opined recently that providing for non-text mode for pg_dumpall would be a Good Thing (TM). Not having it has been a long-standing complaint, so I've decided to give it a go.
I think we would need to restrict it to directory mode, at least to begin with. I would have a toc.dat with a different magic block (say "PGGLO" instead of "PGDMP") containing the global entries (roles, tablespaces, databases). Then for each database there would be a subdirectory (named for its toc entry) with a standard directory mode dump for that database. These could be generated in parallel (possibly by pg_dumpall calling pg_dump for each database). pg_restore on detecting a global type toc.data would restore the globals and then each of the databases (again possibly in parallel).
I'm sure there are many wrinkles I haven't thought of, but I don't see any insurmountable obstacles, just a significant amount of code.
Barring the unforeseen my main is to have a preliminary patch by the September CF.
Following that I would turn my attention to using it in pg_upgrade. cheers andrew -- Andrew Dunstan EDB: https://www.enterprisedb.com
