Hi,
On 8/2/21 6:01 PM, Andres Freund wrote:
> While working on this I found a, somewhat substantial, issue:
>> If so, do you already have in mind a way to handle this? (I thought you
>> already had in mind a way to handle it so the question)
> Yes. I think we need to add a condition variable to be able to wait for
> WAL positions to change. Either multiple condition variables (one for
> the flush position, one for the replay position), or one that just
> changes more often. That way one can wait for apply without a race
> condition.
>
Thanks for the feedback.
Wouldn't a condition variable on the replay position be enough? I don't
get why the proposed one on the flush position is needed.
>> if not, what kind of additional
tests would you like to see?
> A few catalog rows being removed (e.g. due to DELETE and then VACUUM
> *without* full) and a standby without hot_standby_feedback catching
> that.
Test added in v23 attached.
Thanks
Bertrand