Re: [HACKERS] Autovacuum loose ends

Tom Lane wrote:
> "Michael Paesold" <mpaesold@gmx.at> writes:
> > Alvaro Herrera wrote:
> >> I still haven't added custom cost-based delays, but I don't see that as
> >> a showstopper for removing it.  I just went through the CVS log and I
> >> don't see anything else that applies.
>
> > I think you should at least add an autovacuum specific value for
> > "vacuum_cost_delay" because it turns cost-based vacuum delay on or off.
>
> It occurs to me that you could have that today, using the knowledge that
> the autovac daemon runs as the bootstrap user: use ALTER USER SET to
> attach user-specific vacuum delay settings to that role.  This is a
> pretty bletcherous solution, because (a) it requires knowledge of an
> undocumented implementation detail and (b) it would interfere with using
> that role for normal manual maintenance.  So I agree that a few extra
> GUC settings would be better.  But we could get away without 'em.
>
> Along the same lines, it was suggested that we need a way to disable
> stats gathering on a per-database basis.  We already have it: you can
> use ALTER DATABASE SET to control stats_row_level and stats_block_level
> that way.  Neither of the above two objections apply to this usage, so
> I think we can mark off that wishlist item as "done".  (Of course, the
> soon-to-appear autovac documentation had better mention this trick.)

I am thinking we should move ahead with what we have now, suggest the
work-arounds, and thensee what use-cases we have for it for later
releases.

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