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From: Greg Sabino Mullane <htamfids@gmail.com>
Date: Fri, 30 May 2025 20:13:45 -0400
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Subject: Re: POC: Carefully exposing information without authentication
To: Antonin Houska <ah@cybertec.at>
Cc: "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
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On Fri, May 30, 2025 at 11:02=E2=80=AFAM Antonin Houska <ah@cybertec.at> wr=
ote:

> Why is it important not to fork?


Good question. Forking is expensive, and there is also a lot of
housekeeping associated with it that is simply not needed here. We want
this to be lightweight, and simple. No need to fork if we are just going to
do a few strncmp() calls and a send(). However, I'm not highly opposed to
fork-first, as I understand that we want to not slow down postmaster. My
testing showed a barely measurable impact, but I will defer to whatever
decision the elder Postgres gods decide on.


> My understanding is that pg_is_ready also tries to start a regular
> connection, i.e. forks a new backend.


Yep. I consider pg_isready a spiritual cousin to this feature, but it's not
something that can really do what this does.

Cheers,
Greg

--
Crunchy Data - https://www.crunchydata.com
Enterprise Postgres Software Products & Tech Support

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<div dir=3D"ltr"><div dir=3D"ltr">On Fri, May 30, 2025 at 11:02=E2=80=AFAM =
Antonin Houska &lt;<a href=3D"mailto:ah@cybertec.at">ah@cybertec.at</a>&gt;=
 wrote:</div><div class=3D"gmail_quote gmail_quote_container"><blockquote c=
lass=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px soli=
d rgb(204,204,204);padding-left:1ex">Why is it important not to fork?</bloc=
kquote><div><br></div><div>Good question. Forking is expensive, and there i=
s also a lot of housekeeping associated with it that is simply not needed h=
ere. We want this to be lightweight, and simple. No need to fork if we are =
just going to do a few strncmp() calls and a send(). However, I&#39;m not h=
ighly opposed to fork-first, as I understand that we want to not slow down =
postmaster. My testing showed a barely measurable impact, but I will defer =
to whatever decision the elder Postgres gods decide on.</div><div>=C2=A0</d=
iv><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;bord=
er-left:1px solid rgb(204,204,204);padding-left:1ex">My understanding is th=
at pg_is_ready also tries to start a regular connection, i.e. forks a new b=
ackend.</blockquote><div><br></div><div>Yep. I consider pg_isready a spirit=
ual cousin to this feature, but it&#39;s not something that can really do w=
hat this does.</div><div>=C2=A0</div></div><div>Cheers,</div><div dir=3D"lt=
r" class=3D"gmail_signature"><div dir=3D"ltr"><div>Greg</div><div><br></div=
><div>--</div><div>Crunchy Data - <a href=3D"https://www.crunchydata.com" t=
arget=3D"_blank">https://www.crunchydata.com</a></div><div>Enterprise Postg=
res Software Products &amp; Tech Support</div><div><br></div></div></div></=
div>

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