Re: Auto-analyse on insert operations

On 11/04/2015 05:32 AM, Bertrand Roos wrote:
> Hello,
>
> I try to configure auto-analyse task with postgresql 9.4.
> I have the following configuration (default configuration):
> track_counts = on
> autovacuum = on
> log_autovacuum_min_duration = -1
> autovacuum_max_workers = 3
> autovacuum_naptime = 300s
> autovacuum_vacuum_threshold = 50
> autovacuum_analyze_threshold = 50
> autovacuum_vacuum_scale_factor = 0.2
> autovacuum_analyze_scale_factor = 0.2
> autovacuum_freeze_max_age = 200000000
> autovacuum_multixact_freeze_max_age = 400000000
> autovacuum_vacuum_cost_delay = 20ms
> autovacuum_vacuum_cost_limit = -1
>
> With this configuration, I can observe that some tables are
> auto-analysed, but some others are not. Even if there are millions of
> insert operations on an empty table (all tables are in cluster mode).
> In fact it seems that tables with update operations are the only ones
> that are auto-analysed.
> I'm quite suprised because the documentation says that daemon check the
> count of insert, update and delete operations.
> What could it be the reason ? Why tables which have only update
> operation, aren't analysed ?
> Are update operations really taken into account ?

Somewhere you switched actions. You start by saying updated tables are
being analyzed and end by saying they are not, or are the last sentences
supposed to refer to inserts?

>
> Thanks,
>
> Bertrand
>
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com