Re: doc: Improve description of io_combine_limit and io_max_combine_limit GUCs

> On Nov 5, 2025, at 21:58, Karina Litskevich <litskevichkarina@gmail.com> wrote:
> 
> 
> 
> I'm attaching these changes as a separate patch just in case. You can
> squash them if you like. Not sure what to do with the commitfest entry.
> Should I change it back to Needs review?
> 
> Best regards,
> Karina Litskevich
> Postgres Professional: http://postgrespro.com/
> <v2-0002-doc-Fix-description-of-GUCs-with-PGC_POSTMASTER-c.patch><v2-0001-doc-Improve-description-of-io_combine_limit-and-i.patch>

```
-        This parameter can only be set in the <filename>postgresql.conf</filename>
-        file or on the server command line.
+        This parameter can only be set at server start.
```

I think this change will lose information. Actually, I think that even the original message is not accurate enough. For PGC_POSTMASTER parameters, there are 3 ways to update their values:

* Editing postgres.conf
* server command line 
* ALTER SYSTEM, updating postgres.auto.conf

But all require a server restart. The original doc misses “ALTER SYSTEM”, and your change just hides all methods. So I would suggest:

```
This parameter can only be set at server start (for example, in postgresql.conf, via ALTER SYSTEM, or on the server command line).
```

Fujii-san, what do you think?

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/