Hi why, backend_xmin from pg_stat_replication is not updated, although used related replication slot effectively use something like this and blocks removing dead tuples?
postgres=# select slot_name, age(xmin) from pg_replication_slots; -[ RECORD 1 ]--------- slot_name | readonly01 age | 11162 -[ RECORD 2 ]--------- slot_name | readonly02 age | 196 postgres=# select * from pg_stat_replication; -[ RECORD 1 ]----+------------------------------ pid | 7715 usesysid | 16597 usename | repmgr application_name | walreceiver client_addr | xxxxx.2 client_hostname | client_port | 56266 backend_start | 2025-02-20 01:05:50.015719+01 backend_xmin | state | streaming sent_lsn | E154/773EA620 write_lsn | E154/773EA620 flush_lsn | E154/773EA620 replay_lsn | E154/773EA620 write_lag | 00:00:00.00024 flush_lag | 00:00:00.000625 replay_lag | 00:00:00.000754 sync_priority | 0 sync_state | async reply_time | 2025-05-29 07:03:48.827431+02 -[ RECORD 2 ]----+------------------------------ pid | 4097782 usesysid | 16597 usename | repmgr application_name | walreceiver client_addr | xxxxx.1 client_hostname | client_port | 42806 backend_start | 2025-05-28 05:12:43.210414+02 backend_xmin | state | streaming sent_lsn | E154/4F31E000 write_lsn | E154/4F000000 flush_lsn | E154/4F000000 replay_lsn | E154/2141B1C8 write_lag | 00:02:06.153229 flush_lag | 00:02:06.153229 replay_lag | 00:02:48.65516 sync_priority | 0 sync_state | async reply_time | 2025-05-29 07:03:48.818324+02 It is a little bit confusing. Regards Pavel
