Re: doc fix for pg_stat_activity.backend_type

On 11/13/18, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> On Tue, Nov 13, 2018 at 12:04 PM John Naylor <jcnaylor(at)gmail(dot)com> wrote:
>>
>> On 11/13/18, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>> > On Tue, Nov 13, 2018 at 5:38 AM Michael Paquier <michael(at)paquier(dot)xyz>
>> > wrote:
>> >>
>> >> On Mon, Nov 12, 2018 at 09:42:45PM +0700, John Naylor wrote:
>> >> > Looks like it. A quick search revealed "parallel worker" and
>> >> > "logical
>> >> > replication worker". src/test/modules/ also show "test_shm_mq" and
>> >> > "worker_spi", but it seems those don't need to be publicly
>> >> > documented.
>> >> > If that sounds right I'll update the patch to include the first two.
>> >>
>> >> Just wondering: do we actually need to include in the docs this list
>> >> at
>> >> all? This is a recipe to forget its update each time a new backend
>> >> type
>> >> is added.
>> >>
>> >
>> > Sure, but how will we justify documenting (autovacuum launcher and
>> > autovacuum worker) and not (logical replication launcher and logical
>> > replication worker)? I think we can document the type of workers that
>> > are part of core-server functionality. We can make some generic
>> > statement on the workers that can be launched by extensions.
>>
>> How about something like the attached?
>>
>
> Don't you need to remove <literal>background worker</literal>?

It's handled in pgstat_get_backend_desc(), so I assumed not. If that's
just a place holder, then it's probably better left out, as in the
attached.

> + In addition, extensions may have additional types.
>
> How about: "In addition, background workers registered by extensions
> may have additional types."?

Sounds good to me -- I've included this language.

-John Naylor