Re: PG 17 and GUC variables

On Thu, Jun 20, 2024 at 10:03 PM Michael Paquier <michael@paquier.xyz> wrote:
>
> On Thu, Jun 20, 2024 at 08:01:19PM -0400, Bruce Momjian wrote:
> > FYI, looking at the release notes, I see 15 GUC variables added in this
> > release, and two removed.  That 15 number seemed unusually high so I
> > thought I would report it.
>
> Scanning pg_settings across the two versions, I'm seeing:
> - Removed GUCs between 16 and 17:
> db_user_namespace
> old_snapshot_threshold
> trace_recovery_messages
>
> - Added GUCs between 16 and 17:
> allow_alter_system
> commit_timestamp_buffers
> enable_group_by_reordering
> event_triggers
> huge_pages_status
> io_combine_limit
> max_notify_queue_pages
> multixact_member_buffers
> multixact_offset_buffers
> notify_buffers
> serializable_buffers
> standby_slot_names
> subtransaction_buffers
> summarize_wal
> sync_replication_slots
> trace_connection_negotiation
> transaction_buffers
> transaction_timeout
> wal_summary_keep_time
>

I was looking at trace_connection_negotiation and ran across this
commit removing it's mention from the release notes because it is
undocumented:
https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=95cabf542f04b634303f899600ea62fb256a08c2

Why is the right solution to remove it from the release notes rather
than to document it properly? It's not like people won't notice a new
GUC has popped up in their configs. Also, presumaing I'm unerstanding
it's purpose correctly, ISTM it would fit along side other trace_*
gucs in https://www.postgresql.org/docs/current/runtime-config-developer.html#RUNTIME-CONFIG-DEVELOPER.

Robert Treat
https://xzilla.net