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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Clive Boughton <clive.boughton@softimp.com.au>
cc: pgsql-performance@postgresql.org
Subject: Re: A serious change in performance between PG 15 and PG 16, 17, 18.
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Comments: In-reply-to Clive Boughton <clive.boughton@softimp.com.au>
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Clive Boughton <clive.boughton@softimp.com.au> writes:
> When I recently upgraded to PG 18.1 (without any changes to the DB funct=
ions or tables, or indexing) it took 7-10 hours to produce the same result=
 - a 300-600 times decrease in performance.

This complaint is completely un-actionable for lack of relevant
details.  There are some hints here about describing performance
problems usefully:

https://wiki.postgresql.org/wiki/Slow_Query_Questions

			regards, tom lane