> What might make sense is something like pg_dump_restore which would have > no intermediate storage at all, just pump the data etc from one source > to another in parallel
That's right, I implemented that as an own output format and named it "migrator" I think, which wouldn't write each stream to a file as the directory output format does but that instead pumps it back into a restore client.
I could revisit that patch for 9.4 if enough people are interested.
Joachim
As the OP, I'll just note that my organization would definitely find use for a parallel migrator tool as long as it supported doing a selection of tables (i.e. -t / -T) in addition to the whole database and it supported or we were able to patch in an option to cluster as part of the migration (the equivalent of something like https://github.com/tgarnett/postgres/commit/cc320a71 ).