Re: 9.6 query slower than 9.5.3 - Mailing list pgsql-performance

From Adam Brusselback
Subject Re: 9.6 query slower than 9.5.3
Date
Msg-id CAMjNa7eNg538eSD9tzt7AC_S2b+AAdoZe0J5yLTK7w_gTFta_w@mail.gmail.com
Whole thread Raw
In response to Re: 9.6 query slower than 9.5.3  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: 9.6 query slower than 9.5.3  (Adam Brusselback <adambrusselback@gmail.com>)
List pgsql-performance
I analyzed all tables involved after loading, and also while trying to diagnose this issue.

I have the same statistics target settings on both servers.

Here are the schemas for the tables:

On Thu, Jun 16, 2016 at 10:04 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
Adam Brusselback <adambrusselback@gmail.com> writes:
> Hey all, testing out 9.6 beta 1 right now on Debian 8.5.
> I have a query that is much slower on 9.6 than 9.5.3.

The rowcount estimates in 9.6 seem way off.  Did you ANALYZE the tables
after loading them into 9.6?  Maybe you forgot some statistics target
settings?

If it's not that, I wonder whether the misestimates are connected to the
foreign-key-based estimation feature.  Are there any FKs on the tables
involved?  May we see the table schemas?

                        regards, tom lane

pgsql-performance by date:

Previous
From: Tom Lane
Date:
Subject: Re: 9.6 query slower than 9.5.3
Next
From: Adam Brusselback
Date:
Subject: Re: 9.6 query slower than 9.5.3