public inbox for [email protected]  

help / color / mirror / Atom feed

From: Adrian Klaver <[email protected]>
To: Simon Windsor <[email protected]>
To: Laurenz Albe <[email protected]>
To: [email protected]
Subject: Re: Slow timestamp query after upgrading from Pg13 to Pg16
Date: Mon, 7 Apr 2025 12:36:32 -0700
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
	<[email protected]>
	<[email protected]>

On 4/7/25 12:25, Simon Windsor wrote:
> Hi
> 
> We used pg_dump|pg_restore to migrate the data.

Did you do an ANALYZE on the Postgres 16 instance after the pg_restore?

> 
> The full explain plan is at https://explain.depesz.com/s/742M. The SQL
> 
> explain (analyze, buffers) select count(*) from consignments where 
> (req_status_tstamp >= '2025-03-28 00:00'::timestamp and 
> req_status_tstamp <= '2025-03-28 01:00'::timestamp);
> 
> takes 2-3s with the old Pg13 DB, and over a minute with Pg16

Do you have an EXPLAIN ANALYZE for the Postgres 13 case?

> 
> After spending many hours looking at DB settings and Statistic settings 
> I am at a loss/
> 
> Simon
> 


-- 
Adrian Klaver
[email protected]

view thread (4+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: Slow timestamp query after upgrading from Pg13 to Pg16
  In-Reply-To: <[email protected]>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox