Re: Big performance slowdown from 11.2 to 13.3

Justin Pryzby <pryzby@telsasoft.com>

From: Justin Pryzby <pryzby@telsasoft.com>
To: Laurent Hasson <ldh@laurent-hasson.com>
Cc: pgsql-performance@postgresql.org
Date: 2021-07-21T19:15:28Z
Lists: pgsql-performance
On Wed, Jul 21, 2021 at 06:50:58PM +0000, ldh@laurent-hasson.com wrote:
> The plans are pretty much identical too. I checked line by line and couldn't see anything much different (note that I have a view over this query). Here is the V13 version of the plan:

> I am out of my wits as to what is causing such a massive slowdown and how I could fix it.
> 
> Any idea out there?

Could you send the "explain (analyze,buffers,settings) for query on the v11 and
v13 instances ?

Or a link to the execution plan pasted into explain.depesz.com.

https://wiki.postgresql.org/wiki/Slow_Query_Questions#EXPLAIN_.28ANALYZE.2C_BUFFERS.29.2C_not_just_EXPLAIN

It might be good to check using a copy of your data that there's no regression
between 11.2 and 11.12.

-- 
Justin



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