Re: Why does logical replication launcher set application_name?

On 4/18/17 12:37, Tom Lane wrote:
> Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com> writes:
>> I think showing bgw_name as backend_type always sounds reasonable. No
>> need to treat external implementations differently.
>
> That's definitely an approach we could use. It would encourage people
> to use short bgw_names, which is a constraint that wasn't especially
> apparent before, but I don't think that's a bad thing.

Actually, bgw_name is probably not food for
pg_stat_activity.backend_type, since it's often not the same for all
background workers of the same kind. For example, it might be "parallel
worker for PID %d". Ideally, a background worker would have a bgw_type
field and perhaps a bgw_name_extra field. However, a background worker
might also want to update some part of that dynamically, to change the
process title. Many details depend on the particular background workers.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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