(pg17) monitor logical slot sync

[hunleyd]

Describe the enhancement you are proposing:

pg_replication_slot is changed in pg17 to show if logical slots are in sync or not. would be nice to have a metric around that. see this blog.

[keithf4]

Will review this once PG17 is released and the full feature set of this has been finalized and documented.

Right now, hard to tell if the synced column is something that will periodically change and may be false for periods of time while the slot info is being updated. Might need to have a bit of a delay on this as an alert.

[keithf4]

Will definitely have the new metrics for this in for 5.2. Need to do some further investigation to how the failover and synced columns actually work to make a sane alert for them. But at least they'll be there if someone else wants to try and do that too. Added some additional other slot related metrics too

[keithf4]

Will work on adding alerts for this after the next version is out and the metrics are available. Will be easier to evaluate and test then