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From: Xuneng Zhou <xunengzhou@gmail.com>
Date: Mon, 16 Mar 2026 11:05:42 +0800
Message-ID: 
 <CABPTF7VsyyLOehrgj3E2G4yYFwS=sRZofXCtX9R-cAPojfLz2A@mail.gmail.com>
Subject: Re: Streamify more code paths
To: Michael Paquier <michael@paquier.xyz>
Cc: Andres Freund <andres@anarazel.de>,
 pgsql-hackers <pgsql-hackers@lists.postgresql.org>,
	Nazir Bilal Yavuz <byavuz81@gmail.com>
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On Mon, Mar 16, 2026 at 9:00=E2=80=AFAM Michael Paquier <michael@paquier.xy=
z> wrote:
>
> On Sun, Mar 15, 2026 at 11:47:06AM +0800, Xuneng Zhou wrote:
> > The updated script now reports speedup separately for the read and
> > write paths like this:
> >
> > hash_vacuum_medium         base=3D 33747.2ms  patch=3D 27379.7ms   1.23=
x  ( 18.9%)
> >                              read:  4662=E2=86=921612 ops  8238.72=E2=
=86=921725.86ms
> > (4.77x)    write:  12689=E2=86=9212651 ops  25146.51=E2=86=9225053.57ms=
  (1.00x)
> >
> > I think it is useful to keep the write-delay option even with this
> > reporting. Separating the read and write delays also helps reduce the
> > overall runtime of the tests, especially for large data sizes: we only
> > slow down the read path while keeping the write path fast.
>
> These write numbers are more in line with what I was seeing in my last
> tests, and I am not going to ignore a 20% runtime reduction.  The
> stats numbers are looking nice, as well.
>
> At the end, I have checked the logic of what you are introducing,
> where things come down to the point of making sure that the data
> pushed to the callback remains consistent with the paths where
> _hash_getcachedmetap() is called.  I have also cross-checked the data
> reports by pgstattuple for the relation and the index, to see that
> these are consistent between HEAD and the patch, just in case.  And
> applied it.  That was the last piece.
> --
> Michael

Thanks for double-checking and pushing it.

--=20
Best,
Xuneng