> One option that I've heard before is to have vacuum after a single iteration
> (ie, after it fills maintenance_work_mem and does the index cleanup and the
> second heap pass), remember where it was and pick up from that point next
> time.
>From my experience this is not acceptable... I have tables for which the
index cleanup takes hours, so no matter how low I would set the
maintenance_work_mem (in fact I set it high enough so there's only one
iteration), it will take too much time so the queue tables get overly
bloated (not happening either, they get now special "cluster"
treatment).
Cheers,
Csaba.