On Mon, Mar 25, 2024 at 1:37 PM Bertrand Drouvot <bertranddrouvot...@gmail.com> wrote: > > Hi, > > Yeah, and I can see last_inactive_time is moving on the standby (while not the > case on the primary), probably due to the sync worker slot acquisition/release > which does not seem right. >
Yes, you are right, last_inactive_time keeps on moving for synced slots on standby. Once I disabled slot-sync worker, then it is constant. Then it only changes if I call pg_sync_replication_slots(). On a different note, I noticed that we allow altering inactive_timeout for synced-slots on standby. And again overwrite it with the primary's value in the next sync cycle. Steps: ==================== --Check pg_replication_slots for synced slot on standby, inactive_timeout is 120 slot_name | failover | synced | active | inactive_timeout ---------------+----------+--------+--------+------------------ logical_slot1 | t | t | f | 120 --Alter on standby SELECT 'alter' FROM pg_alter_replication_slot('logical_slot1', 900); --Check pg_replication_slots: slot_name | failover | synced | active | inactive_timeout ---------------+----------+--------+--------+------------------ logical_slot1 | t | t | f | 900 --Run sync function SELECT pg_sync_replication_slots(); --check again, inactive_timeout is set back to primary's value. slot_name | failover | synced | active | inactive_timeout ---------------+----------+--------+--------+------------------ logical_slot1 | t | t | f | 120 ==================== I feel altering synced slot's inactive_timeout should be prohibited on standby. It should be in sync with primary always. Thoughts? I am listing the concerns raised by me: 1) create-subscription with create_slot=false overwriting inactive_timeout of existing slot ([1]) 2) last_inactive_time set for synced slots may result in invalidation of slot on promotion. ([2]) 3) alter replication slot to alter inactive_timout for synced slots on standby, should this be allowed? [1]: https://www.postgresql.org/message-id/CAJpy0uAqBi%2BGbNn2ngJ-A_Z905CD3ss896bqY2ACUjGiF1Gkng%40mail.gmail.com [2]: https://www.postgresql.org/message-id/CAJpy0uCLu%2BmqAwAMum%3DpXE9YYsy0BE7hOSw_Wno5vjwpFY%3D63g%40mail.gmail.com thanks Shveta