Re: Replication slot stats misgivings

Hi,

On 2021-03-26 07:58:58 +0530, Amit Kapila wrote:
> On Fri, Mar 26, 2021 at 1:17 AM Andres Freund <andres(at)anarazel(dot)de> wrote:
> > I suggest we wait doing anything about this until we know if the shared
> > stats patch gets in or not (I'd give it 50% maybe). If it does get in
> > things get a good bit easier, because we don't have to deal with the
> > message loss issues anymore.
> >
>
> Okay, that makes sense.

Any chance you could write a tap test exercising a few of these cases?
E.g. things like:

- create a few slots, drop one of them, shut down, start up, verify
stats are still sane
- create a few slots, shut down, manually remove a slot, lower
max_replication_slots, start up

IMO, independent of the shutdown / startup issue, it'd be worth writing
a patch tracking the bytes sent independently of the slot stats storage
issues. That would also make the testing for the above cheaper...

Greetings,

Andres Freund