Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?

From: David Geier <geidav(dot)pg(at)gmail(dot)com>
To: Robert Haas <robertmhaas(at)gmail(dot)com>, Álvaro Herrera <alvherre(at)kurilemu(dot)de>
Cc: Lukas Fittl <lukas(at)fittl(dot)com>, Andres Freund <andres(at)anarazel(dot)de>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>, vignesh C <vignesh21(at)gmail(dot)com>, Michael Paquier <michael(at)paquier(dot)xyz>, Ibrar Ahmed <ibrar(dot)ahmad(at)gmail(dot)com>, Maciek Sakrejda <m(dot)sakrejda(at)gmail(dot)com>, Tomas Vondra <tomas(at)vondra(dot)me>
Subject: Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?
Date: 2025-12-04 08:07:20
Message-ID: 3bd5074a-4d7c-4dc9-8c70-afbe3818a4b1@gmail.com
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 03.12.2025 10:50, David Geier wrote:
> On 19.11.2025 08:20, David Geier wrote:
>>
>> On 20.10.2025 21:59, Robert Haas wrote:
>>> On Sun, Oct 19, 2025 at 2:16 PM Álvaro Herrera <alvherre(at)kurilemu(dot)de> wrote:
>>>> If I were
>>>> a consultant trying to understand a customer's system, I would have to
>>>> ask them to run it twice just in case 'fast' is supported, and I don't
>>>> think that's very helpful.
>>>
>>> Big +1 from me.
>>>
>>
>> That makes sense. I'm planning to rebase the patch the next days. Then
>> I'll also take care of that.
>
> The attached patched is rebased on latest master and pg_test_timing now
> always tests the normal and the fast timing code. If no fast clock
> source is available the fast timing code is skipped.
The last patch I sent was incomplete because I had missed committing my
changes. Attached is now the patch with the changes to pg_test_timing.

--
David Geier

Attachment Content-Type Size
v13-0002-pg_test_timing-Also-test-fast-timing-and-report-time.patch text/x-patch 7.6 KB
v13-0001-Use-time-stamp-counter-to-measure-time-on-Linux-x86.patch text/x-patch 17.2 KB

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Masahiko Sawada 2025-12-04 08:23:53 Re: POC: enable logical decoding when wal_level = 'replica' without a server restart
Previous Message Michael Paquier 2025-12-04 07:42:16 Re: Improve error reporting in 027_stream_regress test