Re: Why does logical replication launcher set application_name?

On Tue, Apr 11, 2017 at 8:11 PM, Michael Paquier
<michael(dot)paquier(at)gmail(dot)com> wrote:
> On Wed, Apr 12, 2017 at 3:40 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> I notice looking at pg_stat_activity that the logical replication launcher
>> sets its application_name to "logical replication launcher". This seems
>> inconsistent (no other standard background process sets application_name),
>> redundant with other columns that already tell you what it is, and an
>> unreasonable consumption of horizontal space in the tabular output.
>> Can we drop that? If we do have to have something like that, what about
>> putting it in the "query" field where it's much less likely to be
>> substantially wider than any other entry in the column?
>
> It seems to me that the logic behind that is to be able to identify
> easily the logical replication launcher in pg_stat_activity, so using
> the query field instead sounds fine for me as we need another way than
> backend_type to guess what is this bgworker.

Wait, why do we need two ways?

--
Robert Haas
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