Re: Libpq support to connect to standby server as priority

On Sat, Nov 17, 2018 at 4:56 AM Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at>
wrote:

> Tom Lane wrote:
> > > As it is now, the patch doesn't keep two connections open. It
> remembers
> > > the index of the host of the first successful writable connection, but
> > > closes the connection, and opens another one to that host if no
> read-only
> > > host can be found.
> >
> > Oh! The reason I assumed it wasn't doing that is that such a behavior
> > seems completely insane. If the point is to keep down the load on your
> > master server, then connecting only to immediately disconnect is not
> > a friendly way to do that --- even without counting the fact that you
> > might later come back and connect again.
>
> That's why I had argued initially to keep the session open, but you
> seem to dislike that idea as well.
>

Yes, we need either session open or reconnect it approach to find out
the whether server is read-write or read-only.

And also for read-only or prefer-read connection types, once after the
connection establishment is done, later server promotes to read-write,
I feel we can continue the connection, that decision makes the feature
simple, or do we want to stop the connection?

Regards,
Haribabu Kommi
Fujitsu Australia