How to kill a Background worker and Its metadata

Hi,

I've created a background worker and I am using Postgresql-9.4. This
bgworker handles the job queue dynamically and goes to sleep if there is no
job to process within the next 1 hour.

Now, I want to have a mechanism to wake the bgworker up in case if someone
adds a new job while the bgworker is in sleep mode. So to do it, I have
created a trigger which initially removes the existing background worker
and then registers a new one. I am using the following two queries inside
it:

select pg_terminate_backend(pid of bgworker);
select worker_spi1_launch(1);

I am retrieving the pid from pg_Stat_activity. The maximum number of
background worker that can run simultaneously is equal to 8. I think even
if I call pg_terminate_backend the metadata of the background worker is not
being deleted and as a result after 8 insert operations I am not able to
register a background worker. Please suggest what can be done here.

Best,
Akash