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In-Reply-To: 
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From: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Date: Mon, 17 Nov 2025 10:28:08 +0530
Message-ID: 
 <CAExHW5vFMkBfv9zB3c5gxF=VLkR7dxM2a3pSFsNuz4JYqc8wRA@mail.gmail.com>
Subject: Re: Idea to enhance pgbench by more modes to generate data
 (multi-TXNs, UNNEST, COPY BINARY)
To: Boris Mironov <boris_mironov@outlook.com>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
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On Fri, Nov 14, 2025 at 8:51=E2=80=AFPM Boris Mironov <boris_mironov@outloo=
k.com> wrote:
>
> Hi Ashutosh,
>
> > If there is one method that is better than all others, community will
> > be more willing to accept implementation of that one method than
> > multiple implementations so as to reduce maintenance burden.
>
> Ok then. I'll leave "COPY FROM STDIN BINARY" implementation out of 3 only=
.
> Would you prefer to replace original COPY FROM STDIN TEXT by this
> code or add it as new "init-step" (e.g., with code "c")?
>

TEXT copy may be useful for cross platform client side data
generation. BINARY might be useful for same platform client side
generation or server side generation. Just a thought, use TEXT or
BINARY automatically based on where it's cross-platform or same
platform setup.

> I also have noted that current code doesn't prevent pgbench parameter
> like "--init-steps=3DdtgG". It allows to run data generation step twice.
> Each of these "g" and "G" will present own timing in status line. Is this
> an oversight or intentional?
>

I would review the commit a386942bd29b0ef0c9df061392659880d22cdf43 and
the discussion thread
https://postgr.es/m/alpine.DEB.2.21.1904061826420.3678@lancre
mentioned in the commit message to find that out. At first glance it
looks like an oversight, but I haven't reviewed the commit and thread
myself. That thread might reveal why generate_series() was used
instead of BINARY COPY for server side data generation. If it needs to
change it's better to start a separate thread and separate patch for
that discussion.


--
Best Wishes,
Ashutosh Bapat