Re: Perplexing, regular decline in performance

I didn't say do it all the time, I said if he hasn't done it already he
should try that as a way of ensuring the database server's understanding of
the data as it stands is correct. Otherwise there isn't enough information
to suggest other solutions as there is no description of the operating
system or resources available to the database server itself. Regardless, if
you have better suggestions please serve them up. :-)

-- Ben Scherrey

On Tue, Jun 25, 2019 at 11:01 PM Justin Pryzby <pryzby(at)telsasoft(dot)com> wrote:

> On Tue, Jun 25, 2019 at 10:55:22PM +0700, Benjamin Scherrey wrote:
> > Have you done a VACUUM ANALYZE FULL on your database? This needs to be
> done
> > periodically to inform the server of the statistics of how the data and
> > relations are distributed across the database.
>
> I think this is wrong.
>
> VACUUM and ANALYZE are good, but normally happen automatically by
> autovacuum.
>
> VACUUM FULL takes an exclusive lock on the table, and rewrites its data and
> indices from scratch. It's not normally necessary at all. It's probably
> most
> useful to recover from badly-bloated table if autovacuum didn't run often
> enough, in which case the permanent solution is to change autovacuum
> settings
> to be more aggressive.
>
> Don't confuse with VACUUM FREEZE, which doesn't require exclusive lock, and
> normally not necessary if autovacuum is working properly.
>
> Justin
>