Re: BUG #15912: The units of `autovacuum_vacuum_cost_delay` settingshould be documented

> On 16 Jul 2019, at 18:26, PG Bug reporting form <noreply@postgresql.org> wrote:
>
> The following bug has been logged on the website:
>
> Bug reference:      15912
> Logged by:          Basil Bourque
> Email address:      basil.bourque@gmail.com
> PostgreSQL version: 12beta2
> Operating system:   macOS
> Description:
>
> The `autovacuum_vacuum_cost_delay` setting:
>
> https://www.postgresql.org/docs/devel/runtime-config-autovacuum.html#GUC-AUTOVACUUM-VACUUM-COST-DELAY
>
> …does not specify its units (seconds? milliseconds?) explicitly.

The description of the setting contains "The default value is 2 milliseconds.”
which to me implies that the unit is measured in milliseconds.  If we want to
spell it out, we could add the unit like how many other on the same page does:

-        Specifies the cost delay value that will be used in automatic
+        Specifies the cost delay value (in milliseconds) that will be used in automatic

cheers ./daniel