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Johnston" Date: Sun, 15 Feb 2026 21:04:35 -0700 X-Gm-Features: AaiRm520jvOYLqwegzeNB0Sx99QPZZiRA4v4apcl3KsR4QMhv0usAsR6Nhf55VU Message-ID: Subject: Re: A serious change in performance between PG 15 and PG 16, 17, 18. To: Clive Boughton Cc: "pgsql-performance@postgresql.org" Content-Type: multipart/alternative; boundary="000000000000940e49064ae90dd1" List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk --000000000000940e49064ae90dd1 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sunday, February 15, 2026, Clive Boughton wrote: > > > For reasons of security I can't provide all the SQL code, but I can (if i= t > is necessary) provide an outline of what the code does. > If you cannot provide at least explain analyze, before and after, the odds of making progress on this is greatly diminished. A minimal reproducer you can verify and share is exponentially better though. It=E2=80=99s probably worth ensuring JIT is disabled even going off this mi= nimal information. David J. --000000000000940e49064ae90dd1 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sunday, February 15, 2026, Clive Boughton <clive.boughton@softimp.com.au> wrote:
For reasons of security I can't provide all the SQL code, b= ut I can (if it is necessary) provide an outline of what the code does.

If you cannot provide at least exp= lain analyze, before and after, the odds of making progress on this is grea= tly diminished.=C2=A0 A minimal reproducer you can verify and share is expo= nentially better though.

It=E2=80=99s probably wor= th ensuring JIT is disabled even going off this minimal information.
<= div>
David J.

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