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From: Nazir Bilal Yavuz <byavuz81@gmail.com>
Date: Fri, 26 Dec 2025 13:59:24 +0300
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 <CAN55FZ02eR083kPV_8_boWEJphXZW=-hRxJKp7nwR-WomyKb6g@mail.gmail.com>
Subject: Re: Streamify more code paths
To: Xuneng Zhou <xunengzhou@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@lists.postgresql.org>
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Hi,

Thank you for working on this!

On Thu, 25 Dec 2025 at 09:34, Xuneng Zhou <xunengzhou@gmail.com> wrote:
>
> Hi,
>
> On Thu, Dec 25, 2025 at 1:51=E2=80=AFPM Xuneng Zhou <xunengzhou@gmail.com=
> wrote:
> >
> > Hi Hackers,
> >
> > I noticed several additional paths in contrib modules, beyond [1],
> > that are potentially suitable for streamification:
> >
> > 1) pgstattuple =E2=80=94 pgstatapprox.c and parts of pgstattuple_approx=
_internal
> > 2) Bloom =E2=80=94 scan paths in blgetbitmap() and maintenance paths in=
 blbulkdelete()
> >
> > The following patches streamify those code paths. No benchmarks have
> > been run yet.
> >
> > [1] https://www.postgresql.org/message-id/flat/CABPTF7UeN2o-trr9r7K76rZ=
ExnO2M4SLfvTfbUY2CwQjCekgnQ%40mail.gmail.com
> >
> > Feedbacks welcome.
> >
>
> One more in ginvacuumcleanup().

0001, 0002 and 0004 LGTM.

0003:

+        buf =3D read_stream_next_buffer(stream, NULL);
+        if (buf =3D=3D InvalidBuffer)
+            break;

I think we are loosening the check here. We were sure that there were
no InvalidBuffers until the nblocks. Streamified version does not have
this check, it exits from the loop the first time it sees an
InvalidBuffer, which may be wrong. You might want to add
'Assert(p.current_blocknum =3D=3D nblocks);' before read_stream_end() to
have a similar check.

--
Regards,
Nazir Bilal Yavuz
Microsoft