Bruce Momjian <bruce@momjian.us> writes:
> Does anyone know how bad the queries will be with only one target?
Bad. That cycle seems like largely a waste of time. About the only
thing it would do for you is ensure that relpages/reltuples are up to
date, which seems like something we could possibly arrange for during
the data import.
> I did see if vacuumdb --analyze-only was somehow being throttled by the
> vacuum settings, but saw the drive at 100% utilization analying a 36GB
> table on a 24GB RAM server, so it seems I/O bound.
I think it'd be good to explicitly set vacuum_cost_delay to 0 in the
first pass, in the same way as you are forcing
default_statistics_target, just in case somebody has a nondefault
setting for that. The second pass could probably be allowed to use some
higher delay setting.
regards, tom lane