Bruce Momjian <bruce(at)momjian(dot)us> writes:
> Magnus reported that a customer with a million tables was finding
> pg_upgrade slow.
You sure there's not an O(N^2) issue in there somewhere?
> I don't see anything unsafe about having pg_upgrade use
> synchronous_commit=off.
No objection, but this seems unlikely to be better than linear speedup,
with a not-terribly-large constant factor.
BTW, does pg_upgrade run pg_restore in --single-transaction mode?
That would probably make synchronous_commit moot, at least for that
step.
regards, tom lane