On Wed, Jun 10, 2020 at 08:57:17PM +0300, Alexey Kondratov wrote:
> New test reproduces this issue well. Left it running for a couple of hours
> in repeat and it seems to be stable.
Thanks for testing. I have been thinking about the minimum xmin and
LSN computations on advancing, and actually I have switched the
recomputing to be called at the end of pg_replication_slot_advance().
This may be a waste if no advancing is done, but it could also be an
advantage to enforce a recalculation of the thresholds for each
function call. And that's more consistent with the slot copy, drop
and creation.
> we can safely use $current_lsn used for pg_replication_slot_advance(), since
> reatart_lsn is set as is there. It may make the test a bit simpler as well.
We could do that. Now I found cleaner the direct comparison of
pg_replication_slots.restart before and after the restart. So I have
kept it.
--
Michael