OK. Will do another round of testing.
-----Original Message----- From: David Rowley <dgrowle...@gmail.com> Sent: Thursday, July 22, 2021 00:44 To: l...@laurent-hasson.com Cc: Tom Lane <t...@sss.pgh.pa.us>; Peter Geoghegan <p...@bowt.ie>; Justin Pryzby <pry...@telsasoft.com>; pgsql-performa...@postgresql.org Subject: Re: Big performance slowdown from 11.2 to 13.3 On Thu, 22 Jul 2021 at 16:37, l...@laurent-hasson.com <l...@laurent-hasson.com> wrote: > Seems like no cigar ☹ See plan pasted below. I changed the conf as follows: > - hash_mem_multiplier = '2' > - work_mem = '1GB' > Batches: 5 Memory Usage: 2400305kB Disk Usage: 126560kB You might want to keep going higher with hash_mem_multiplier until you see no "Disk Usage" there. As mentioned, v11 didn't spill to disk and just used all the memory it pleased. That was a bit dangerous as it could result in OOM, so it was fixed. David
