Hi Jon,
Regarding vacuum "has shown up to a 6x improvement in overall time to
complete its work" -- I believe I've seen reported numbers close to
that only 1) when measuring the index phase in isolation or maybe 2)
the entire vacuum of unlogged tables with one, perfectly-correlated
index (testing has less variance with WAL out of the picture). I
believe tables with many indexes would show a lot of improvement, but
I'm not aware of testing that case specifically. Can you clarify where
6x came from?
