Обсуждение: Re: Parallelizing startup with many databases

On Sat, 3 Jan 2026 at 20:09, Andreas Karlsson <andreas@proxel.se> wrote:
>
> On 1/3/26 1:58 AM, Jelte Fennema-Nio wrote:
> > PS It took me way to long to find that setting. I think we should move
> > it from the error handling docs page to the page with all of the other
> > recovery settings. https://www.postgresql.org/docs/current/runtime-
> > config-wal.html#RUNTIME-CONFIG-WAL-RECOVERY <https://www.postgresql.org/
> > docs/current/runtime-config-wal.html#RUNTIME-CONFIG-WAL-RECOVERY>
>
> I agree that it is currently not in exactly a great location but the
> issue is that the "Recovery" section is a subsection of the "WAL"
> section, and syncing the data directory is only loosely related to WAL.
> One could argue it is related to WAL as in that it is something done
> before replaying WAL but it is not an obvious location either. Or is it?

<Moving this discussion to pgsql-docs, with accompanying patch>

While the setting is not strictly related to WAL it still seems a much
more natural place than the "Error handling" page. Especially because of
the description of this subheading:

> This section describes the settings that apply to recovery in general,
> affecting crash recovery, streaming replication and archive-based
> replication.

The only recovery related GUC that exists that's not on the WAL page is
recovery_min_apply_delay, which is under the Replication->Standby
section. Since that GUC is only valid on standbys that seems like a
sensible choice.

On 1/4/26 12:26 AM, Jelte Fennema-Nio wrote:
> <Moving this discussion to pgsql-docs, with accompanying patch>
If we move the GUC in the documentation shouldn't we also move it in 
postgresql.conf.sample? The sections in the documentation and the 
sections in the sample config file seem to be the same.

Andreas

Andreas Karlsson <andreas@proxel.se> writes:
> On 1/4/26 12:26 AM, Jelte Fennema-Nio wrote:
>> <Moving this discussion to pgsql-docs, with accompanying patch>

> If we move the GUC in the documentation shouldn't we also move it in 
> postgresql.conf.sample? The sections in the documentation and the 
> sections in the sample config file seem to be the same.

You would also need to change the group that the GUC is assigned to
in guc_parameters.dat.  So this isn't really a docs-only patch.
(I agree that the GUC seems misclassified as-is.)

            regards, tom lane

On Sun Jan 4, 2026 at 1:02 AM CET, Tom Lane wrote:
> Andreas Karlsson <andreas@proxel.se> writes:
>> On 1/4/26 12:26 AM, Jelte Fennema-Nio wrote:
>>> <Moving this discussion to pgsql-docs, with accompanying patch>
>
>> If we move the GUC in the documentation shouldn't we also move it in
>> postgresql.conf.sample? The sections in the documentation and the
>> sections in the sample config file seem to be the same.
>
> You would also need to change the group that the GUC is assigned to
> in guc_parameters.dat.  So this isn't really a docs-only patch.
> (I agree that the GUC seems misclassified as-is.)

Good points. Attached an updated patch that changes
postgresql.conf.sample and the group too.

I didn't move the thread back to pgsql-hackers though, since changing
the location once more seemed counterproductive. Especially since it's
still a docs change at heart.