Horton

Re: First draft of PG 17 release notes

Bruce Momjian <bruce@momjian.us>

View thread
From: Bruce Momjian <bruce@momjian.us>
To: Andres Freund <andres@anarazel.de>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Melanie Plageman <melanieplageman@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2024-05-18T14:59:47Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Revert support for ALTER TABLE ... MERGE/SPLIT PARTITION(S) commands

  2. When creating materialized views, use REFRESH to load data.

  3. Revert temporal primary keys and foreign keys

  4. Avoid needless large memcpys in libpq socket writing

  5. Enhance nbtree ScalarArrayOp execution.

  6. Introduce a non-recursive JSON parser

  7. Combine freezing and pruning steps in VACUUM

  8. Allow SIGINT to cancel psql database reconnections.

  9. Provide API for streaming relation data.

  10. Add hash support functions and hash opclass for contrib/ltree.

  11. Pull up ANY-SUBLINK with the necessary lateral support.

  12. Read WAL directly from WAL buffers.

  13. Introduce the dynamic shared memory registry.

  14. Add macros for looping through a List without a ListCell.

  15. Support +/- infinity in the interval data type.

  16. Extend ALTER OPERATOR to allow setting more optimization attributes.

  17. Consider cheap startup paths in add_paths_to_append_rel

On Wed, May 15, 2024 at 08:48:02PM -0700, Andres Freund wrote:
> Hi,
> 
> On 2024-05-15 10:38:20 +0200, Alvaro Herrera wrote:
> > I disagree with this.  IMO the impact of the Sawada/Naylor change is
> > likely to be enormous for people with large tables and large numbers of
> > tuples to clean up (I know we've had a number of customers in this
> > situation, I can't imagine any Postgres service provider that doesn't).
> > The fact that maintenance_work_mem is no longer capped at 1GB is very
> > important and I think we should mention that explicitly in the release
> > notes, as setting it higher could make a big difference in vacuum run
> > times.
> 
> +many.
> 
> We're having this debate every release. I think the ongoing reticence to note
> performance improvements in the release notes is hurting Postgres.
> 
> For one, performance improvements are one of the prime reason users
> upgrade. Without them being noted anywhere more dense than the commit log,
> it's very hard to figure out what improved for users. A halfway widely
> applicable performance improvement is far more impactful than many of the
> feature changes we do list in the release notes.

I agree the impact of performance improvements are often greater than
the average release note item.  However, if people expect Postgres to be
faster, is it important for them to know _why_ it is faster?

If we add a new flag to a command, people will want to know about it so
they can make use of it, or if there is a performance improvement that
allows new workloads, they will want to know about that too so they can
consider those workloads.

On the flip side, a performance improvement that makes everything 10%
faster has little behavioral change for users, and in fact I think we
get ~6% faster in every major release.

> For another, it's also very frustrating for developers that focus on
> performance. The reticence to note their work, while noting other, far
> smaller, things in the release notes, pretty much tells us that our work isn't
> valued.

Yes, but are we willing to add text that every user will have to read
just for this purpose?

One think we _could_ do is to create a generic performance release note
item saying performance has been improved in the following areas, with
no more details, but we can list the authors on the item.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

  Only you can decide what is important to you.