Re: Autovacuum fails to keep visibility map up-to-date in mostly-insert-only-tables

On 2014-10-09 18:03:00 -0300, Alvaro Herrera wrote:
> Bruce Momjian wrote:
> 
> > I agree this is a serious problem.  We have discussed various options,
> > but have not decided on anything.  The TODO list has:
> > 
> >     https://wiki.postgresql.org/wiki/Todo
> > 
> >     Improve setting of visibility map bits for read-only and insert-only
> >     workloads
> >     
> >       http://www.postgresql.org/message-id/20130906001437.GA29264@momjian.us
> 
> I hate to repeat myself, but I think autovacuum could be modified to run
> actions other than vacuum and analyze.  In this specific case we could
> be running a table scan that checks only pages that don't have the
> all-visible bit set, and see if it can be set.

Isn't that *precisely* what a plain vacuum run does?

Greetings,

Andres Freund

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