Re: Retry Cached Remote Connections for postgres_fdw in case remote backend gets killed/goes away

On Wed, Sep 30, 2020 at 11:32 PM Fujii Masao
<masao(dot)fujii(at)oss(dot)nttdata(dot)com> wrote:
>
> > And another way, if we don't want to use wait_pid() is to have a
> > plpgsql stored procedure, that in a loop keeps on checking for the
> > backed pid from pg_stat_activity, exit when pid is 0. and then proceed
> > to issue the next foreign table query. Thoughts?
>
> +1 for this approach! We can use plpgsql or DO command.
>

Used plpgsql procedure as we have to use the procedure 2 times.

>
> >
> > mypid = -1;
> > while (mypid != 0)
> > SELECT pid INTO mypid FROM pg_stat_activity WHERE backend_type =
> > 'client backend' AND application_name = 'fdw_retry_check';
>
> Or we can just wait for the number of processes with
> appname='fdw_retry_check' to be zero rather than checking the pid.
>

Done.

Attaching v7 patch with above changes. Please review it.

With Regards,
Bharath Rupireddy.
EnterpriseDB: http://www.enterprisedb.com