Re: Up to 50x degradation in dblink performance when receiving notice traffic 19 vs 18

From: Merlin Moncure <mmoncure(at)gmail(dot)com>
To: vignesh C <vignesh21(at)gmail(dot)com>
Cc: PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>, Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Subject: Re: Up to 50x degradation in dblink performance when receiving notice traffic 19 vs 18
Date: 2026-09-24 15:15:22
Message-ID: CAHyXU0za3SOgUGSBLUxxyyywk2LpG6MoB8t3V7Wng-ni9O9z6Q@mail.gmail.com
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Thu, Sep 24, 2026 at 8:50 AM Merlin Moncure <mmoncure(at)gmail(dot)com> wrote:

>
> My work on adding a WaitEventSet based dblink API poll was in part
> inspired by attempting to defend against this issue on the premise that
> sitting around in poll() and being aggressive with consumeinput vs pg_sleep
> latch was somehow more polite to the o/s somehow. Perhaps it's not a bug
> at all, but a simple hardware flush problem that postgres is at the mercy
> of.
>

Quick note: turning off logging collector, then disconnecting the session
that invoked pg_ctl so that logs go nowhere, timings go flat and are fast.
So this smells like hardware.

merlin

>

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Peter Eisentraut 2026-09-24 15:15:28 Re: run pgindent in CI
Previous Message Peter Eisentraut 2026-09-24 15:11:41 convert CI CompilerWarnings job to meson