pg.ddx.io  pgsql-bugs@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Todd Cook <cookt@blackduck.com>
To: Peter Geoghegan <pg@bowt.ie>
Cc: Merlin Moncure <mmoncure@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Sajith Prabhakar Shetty <ssajith@blackduck.com>
Cc: Andrei Lepikhov <lepihov@gmail.com>
Cc: pgsql-bugs@lists.postgresql.org <pgsql-bugs@lists.postgresql.org>
Subject: Re: Postgres: Queries are too slow after upgrading to PG17 from PG15
Date: Fri, 26 Sep 2025 12:30:36 +0000
Message-ID: <BF2F92D9-2208-4CCD-8F4D-8A2F8FBC9F71@blackduck.com> (raw)
In-Reply-To: <CAH2-Wz=zyN7TBvQVGTxqBzE6zSGzbTrsv2bVNUaCBAuHa_ND7w@mail.gmail.com>
References: <PH7PR19MB6481278D3A55C8BD04B9B9EDB590A@PH7PR19MB6481.namprd19.prod.outlook.com>
	<2a8243eb-a8e8-4c2d-9c46-7152782d84f8@gmail.com>
	<DM4PR19MB64869049D2AD4882D114BB90B551A@DM4PR19MB6486.namprd19.prod.outlook.com>
	<CAH2-WzmBXPLn=j+nqwGtzoQiMzjY=otTt1irzb39+NkfnHMsnw@mail.gmail.com>
	<DM4PR19MB6486B947E5F0D800127897F5B551A@DM4PR19MB6486.namprd19.prod.outlook.com>
	<CAH2-Wzkduf6pevzTfGpXr29SoXb9jH6AxAkbJM-cJo1EU0M57Q@mail.gmail.com>
	<DM4PR19MB648605FF2806007FC55C0AA5B55AA@DM4PR19MB6486.namprd19.prod.outlook.com>
	<CAH2-WznCkB0V86y+OO0_pp2NfS14-gM2FbMr9uXx9yjdQkpbxQ@mail.gmail.com>
	<DM4PR19MB6486E73FF04BADFD120A0568B525A@DM4PR19MB6486.namprd19.prod.outlook.com>
	<CAH2-WzmNhY2HWNkPku0ugesSp=AxWyy+9tCaq4YqNMSRV8QDqw@mail.gmail.com>
	<2121299.1753993453@sss.pgh.pa.us>
	<CAH2-Wz=O3C=9EWu1azGuHT-3iz1jOon21vG53xFfwJhiaG2CFg@mail.gmail.com>
	<2128451.1753997128@sss.pgh.pa.us>
	<CAH2-WzmOOBV7wtu3K6R_zO105Qi_BE-2Ki5T9KLsHETP=GQwAA@mail.gmail.com>
	<2532876.1754096999@sss.pgh.pa.us>
	<2538941.1754100308@sss.pgh.pa.us>
	<CAH2-Wzndh_wt-vNxwzUC09dCGMBVr00Z34sf5J8HRNu09gzpSA@mail.gmail.com>
	<AD7A39D2-1A49-4A73-A28B-1720134E013D@blackduck.com>
	<CAHyXU0xgOE99AuTjSAo+SNK_00P=F8JcbdoH3+OcV+zs1r00vA@mail.gmail.com>
	<53859E8F-67E7-4A25-AEE1-C7E472262F47@blackduck.com>
	<DEE6B3DC-B626-4C9F-A7E1-A06D85950ABF@blackduck.com>
	<CAH2-Wz=b5E+Ru4RfE+9QkF56ncH4dWm==SQeOvNGQBDtv_J-Yw@mail.gmail.com>
	<2CB274CF-6282-48F9-988F-59F16E1D0EEC@blackduck.com>
	<CAH2-Wz=zyN7TBvQVGTxqBzE6zSGzbTrsv2bVNUaCBAuHa_ND7w@mail.gmail.com>

On 9/25/25, 3:47 PM, "Peter Geoghegan" <pg@bowt.ie <mailto:pg@bowt.ie>> wrote:
> Should be noted that the regression itself is definitely "a small
> effect that is multiplied by repetition". This makes the problem
> rather perverse (though it's not exactly unusual for a complaint about
> a planner regression to be perverse, in one way or another).

Thanks for confirming.  We can develop a strategy for working around
this effect, so from my point of view, we can consider this matter
resolved.  I'm guessing that you feel the same way, but if not, I'm
happy to help out in any way I can.

In any case, I do appreciate your efforts and the time you took to
write out the very helpful explanations you provided. __

-- todd



view thread (54+ messages)  latest in thread

Message-ID: <BF2F92D9-2208-4CCD-8F4D-8A2F8FBC9F71@blackduck.com>
Permalink:  ../BF2F92D9-2208-4CCD-8F4D-8A2F8FBC9F71@blackduck.com/
Also on:    postgresql.org/message-id/BF2F92D9-2208-4CCD-8F4D-8A2F8FBC9F71@blackduck.com

 · 

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: pgsql-bugs@postgresql.org
  Cc: cookt@blackduck.com, pg@bowt.ie, mmoncure@gmail.com, tgl@sss.pgh.pa.us, ssajith@blackduck.com, lepihov@gmail.com, pgsql-bugs@lists.postgresql.org
  Subject: Re: Postgres: Queries are too slow after upgrading to PG17 from PG15
  In-Reply-To: <BF2F92D9-2208-4CCD-8F4D-8A2F8FBC9F71@blackduck.com>

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

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