Re: First draft of PG 17 release notes

On Fri, May 10, 2024 at 06:50:54PM +0200, Jelte Fennema-Nio wrote:
> On Thu, 9 May 2024 at 06:04, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> >
> > I have committed the first draft of the PG 17 release notes; you can
> > see the results here:
> >
> > https://momjian.us/pgsql_docs/release-17.html
>
> Great work!
>
> There are two commits that I think would benefit from being listed
> (but maybe they are already listed and I somehow missed them, or they
> are left out on purpose for some reason):

I looked at both of these. In both cases I didn't see why the user
would need to know these changes were made:

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> - c4ab7da60617f020e8d75b1584d0754005d71830

commit c4ab7da6061
Author: David Rowley <drowley(at)postgresql(dot)org>
Date: Sun Apr 7 21:20:18 2024 +1200

Avoid needless large memcpys in libpq socket writing

Until now, when calling pq_putmessage to write new data to a libpq
socket, all writes are copied into a buffer and that buffer gets flushed
when full to avoid having to perform small writes to the socket.

There are cases where we must write large amounts of data to the socket,
sometimes larger than the size of the buffer. In this case, it's
wasteful to memcpy this data into the buffer and flush it out, instead,
we can send it directly from the memory location that the data is already
stored in.

Here we adjust internal_putbytes() so that after having just flushed the
buffer to the socket, if the remaining bytes to send is as big or bigger
than the buffer size, we just send directly rather than needlessly
copying into the PqSendBuffer buffer first.

Examples of operations that write large amounts of data in one message
are; outputting large tuples with SELECT or COPY TO STDOUT and
pg_basebackup.

Author: Melih Mutlu
Reviewed-by: Heikki Linnakangas
Reviewed-by: Jelte Fennema-Nio
Reviewed-by: David Rowley
Reviewed-by: Ranier Vilela
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/CAGPVpCR15nosj0f6xe-c2h477zFR88q12e6WjEoEZc8ZYkTh3Q@mail.gmail.com

> - cafe1056558fe07cdc52b95205588fcd80870362

commit cafe1056558
Author: Robert Haas <rhaas(at)postgresql(dot)org>
Date: Tue Apr 2 10:26:10 2024 -0400

Allow SIGINT to cancel psql database reconnections.

After installing the SIGINT handler in psql, SIGINT can no longer cancel
database reconnections. For instance, if the user starts a reconnection
and then needs to do some form of interaction (ie psql is polling),
there is no way to cancel the reconnection process currently.

Use PQconnectStartParams() in order to insert a cancel_pressed check
into the polling loop.

Tristan Partin, reviewed by Gurjeet Singh, Heikki Linnakangas, Jelte
Fennema-Nio, and me.

Discussion: http://postgr.es/m/D08WWCPVHKHN.3QELIKZJ2D9RZ@neon.tech

--
Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

Only you can decide what is important to you.