Horton

Re: PG 14 release notes, first draft

Alvaro Herrera <alvherre@alvh.no-ip.org>

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From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Bruce Momjian <bruce@momjian.us>
Cc: Justin Pryzby <pryzby@telsasoft.com>, pgsql-hackers@postgresql.org
Date: 2021-05-20T20:35:07Z
Lists: pgsql-hackers 
On 2021-May-20, Bruce Momjian wrote:

> On Thu, May 20, 2021 at 02:55:18PM -0500, Justin Pryzby wrote:
> > On Thu, May 20, 2021 at 03:44:46PM -0400, Bruce Momjian wrote:
> > > > | Reduce the default value of vacuum_cost_page_miss (Peter Geoghegan) 
> > > > |  This new default better reflects current hardware capabilities. 
> > > > Also say: the previous default was 10.
> > > 
> > > Uh, we didn't report the new value, so why report the old one?
> > 
> > Good point.
> > For symmetry with this one, maybe the old and new values should be included?
> 
> Not sure.  Those values are kind of hard to understand, so I am afraid
> there would be more confusion by mentioning them.
> 
> > |Change checkpoint_completion_target default to 0.9 (Stephen Frost)
> > |The previous default was 0.5.
> 
> Uh, that one is frequently modified by users, to an extent I didn't
> understand why we kept it at 0.5 for so long, which is why I mentioned
> it.

You also mentioned 'md5' in the entry about password_encryption,
remember?  I tend to agree with Justin: if it's not too much extra space
to mention both values, let's just do that.  "Reduce the value of X to Y
from Z.  The new default better reflects ..." seems OK to me.

I prefer "to Y from Z" rather than "from Z to Y", because then the new
value appears first, which seems a tiny improvement in readability,
though the phrase is in the opposite order of traditional.  Also it
seems better than "change value of X to Y.  The previous default was Z"
because it then becomes a little more verbose than really needed.  But
maybe that's OK too.

-- 
Álvaro Herrera                            39°49'30"S 73°17'W
"La fuerza no está en los medios físicos
sino que reside en una voluntad indomable" (Gandhi)

Commits

  1. doc: add mention of +4GB windows file handling in PG14 relnotes

  2. doc: PG 14 relnotes fixes

  3. doc: PG 14 relnote updates

  4. doc: PG 14 relnotes, adjust pg_{read|write}_all_data entry

  5. Update PG 14 relnotes for vacuum_cost_page_miss

  6. doc: update PG 14 release notes with recent feedback

  7. Update replication statistics after every stream/spill.

  8. Add information of total data processed to replication slot stats.

  9. Use NameData datatype for slotname in stats.

  10. Add back vacuum_cleanup_index_scale_factor parameter.

  11. Don't consider newly inserted tuples in nbtree VACUUM.

  12. pgbench: Improve time logic.

  13. Track total amounts of times spent writing and syncing WAL data to disk.

  14. Allow decoding at prepare time in ReorderBuffer.

  15. Extend the output plugin API to allow decoding of prepared xacts.

  16. Fix nbtree cleanup-only VACUUM stats inaccuracies.

  17. Execute invalidation messages for each XLOG_XACT_INVALIDATIONS message

  18. Fix our Windows stat() emulation to handle file sizes > 4GB.

  19. Trigger autovacuum based on number of INSERTs

  20. Speed up planning when partitions can be pruned at plan time.

  21. Remove support for password_encryption='off' / 'plain'.

  22. Increase work_mem and maintenance_work_mem defaults by 4x