Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?

From: John Naylor <johncnaylorls(at)gmail(dot)com>
To: Lukas Fittl <lukas(at)fittl(dot)com>
Cc: Andres Freund <andres(at)anarazel(dot)de>, Jakub Wartak <jakub(dot)wartak(at)enterprisedb(dot)com>, Hannu Krosing <hannuk(at)google(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, 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>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>, David Geier <geidav(dot)pg(at)gmail(dot)com>
Subject: Re: Reduce timing overhead of EXPLAIN ANALYZE using rdtsc?
Date: 2026-04-05 02:28:59
Message-ID: CANWCAZb12Si+6QWYLCxvhHDmP2L4pOqXoTuxtheu0uZ=TLn-Rg@mail.gmail.com
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Sun, Apr 5, 2026 at 2:00 AM Lukas Fittl <lukas(at)fittl(dot)com> wrote:
>
> On Sat, Apr 4, 2026 at 2:21 AM Lukas Fittl <lukas(at)fittl(dot)com> wrote:
> > See attached v17.
>
> This needed a rebase after 5e13b0f240397b2, see attached v18.
>
> Looking at the changes in that commit, I also ended up re-ordering the
> feature flags in pg_cpu.h, so we have the 128/256/512 bit registers
> first, and then hypervisor and TSC flags after the 512 bit registers.

v18-0002 looks good to me as far as feature-detection, but aside from
that there are plenty of domain-specific details that I lack the means
to check on short notice. I did verify that OSXSAVE support is still
functional.

--
John Naylor
Amazon Web Services

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Peter Geoghegan 2026-04-05 02:29:15 Re: PG 19 release notes and authors
Previous Message Alexander Korotkov 2026-04-05 02:24:48 Re: Asynchronous MergeAppend