Re: Per-table log_autovacuum_min_duration is actually documented

Tom Lane wrote:
> Michael Paquier <michael(dot)paquier(at)gmail(dot)com> writes:
> > On Wed, Nov 11, 2015 at 12:07 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> Should it read "Overrides log_autovacuum_min_duration for autovacuum
> >> operations on this specific table or toast table"?
>
> > The same applied for all the other autovacuum and autoanalyze
> > parameters. Do you think that we should add in the top paragraph of
> > section "Storage Parameters" a mention of the type "If this parameter
> > has a server-wide equivalent parameter, the per-table value overrides
> > its server-wide equivalent if defined" or similar.
>
> There's a whole lot of inconsistency in this area, apparently. Some of
> the entries in runtime-config-autovacuum are marked as being overridable
> by storage parameters, some aren't (in particular this one is not, which
> may be the origin of Bruce's complaint).

log_autovacuum_min_duration was made changeable per-table recently by
commit 4ff695b17d32 of April 2015, having been introduced by commit
9d3b50244357ef4, Nov 2011, while the others have been changeable for a
much longer while, c.f. 834a6da4f72d of Feb 2009.

> Some of the entries in
> SQL-CREATETABLE-storage-parameters use the "custom" phraseology, some
> don't but instead duplicate (or more often, rephrase poorly) the
> documentation of the underlying GUC. I think duplication is a bad
> strategy here. But I still don't care for "custom", perhaps because it's
> been stretched to the point of being nearly meaningless elsewhere in the
> system. "Per-table" is used in other sentences in this same area, and
> that seems like a better description.

Sounds fair.

> I'll try to make this better.

Thanks!

--
Álvaro Herrera http://www.2ndQuadrant.com/
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