Re: Improve pg_sync_replication_slots() to wait for primary to advance

On Tue, Oct 7, 2025 at 3:24 PM Ajin Cherian <itsajin@gmail.com> wrote:
>
> Hello Hackers,
>
> In an offline discussion, I was considering adding a TAP test for this
> patch. However, testing the pg_sync_replication_slots() API’s wait
> logic requires a delay of at least 2 seconds, since that’s the
> interval the API sleeps before retrying. I’m not sure it’s acceptable
> to add a TAP test that increases runtime by 2 seconds.
> I’m also wondering if 2 seconds is too long for the API to wait?
> Should we reduce it to something like 200 ms instead? I’d appreciate
> your feedback.
>

I feel a shorter nap will be good since it is an API and should finish
fast. But too short a nap may result in too many primary pings
specially when primary-slots are not advancing. But that case should
be a rare one. Shall we have a nap of say 500ms? It is neither too
short nor too long. Thoughts?

thanks
Shveta