Re: Autovacuum on partitioned table (autoanalyze)

Hi Justin,

Thank you for commens.

On Tue, Apr 7, 2020 at 12:32 PM Justin Pryzby <pryzby(at)telsasoft(dot)com> wrote:
>
> Not sure if you saw my earlier message ?
>
I'm sorry, I didn't notice for a while.

> I think it ought to be possible to configure this feature such that an
> auto-analyze on any child partition would trigger analyze of the parent. I
> think that would be important for maintaining accurate stats of the partition
> key column for many cases involving RANGE-partitioned tables, which are likely
> to rely on histogram rather than MCVs.
>
I read your previous email and understand that it would be neccesary to analyze
partitioned tables automatically when any of its children are analyzed. In my
first patch, auto-analyze on partitioned tables worked like this but there were
some comments about performance of autovacuum, especially when partitioned
tables have a lot of children.

The latest patch lets users set different autovacuum configuration for
each partitioned
tables like this,
create table p3(i int) partition by range(i) with
(autovacuum_analyze_scale_factor=0.0005, autovacuum_analyze_threshold=100);
so users can configure those parameters according to partitioning strategies
and other requirements.

So I think this patch can solve problem you mentioned.

--
Best regards,
Yuzuko Hosoya
NTT Open Source Software Center