autovacuum is running but pg_stat_all_tables empty

Hi,

I'm trying to understand something that is weird on one of my environments. When I query pg_stat_all_tables I see that most of the tables dont have any value in the last_autovacuum/analyze column. In addition the columns autovacuum_count/analyze_count is set to 0. However, when checking the logs, I see that on some of those tables autovacuum run. I think that there is something wrong with the database statistics collector. In addition, the column n_dead_tup and n_live_tup are set and in some of the cases n_dead_tup is more then 20% of the table tuples. In addition, all tables have default vacuum threshold.

Any idea what else I can check ?

The problem isnt only that dead tuples arent deleted (I dont have long running transaction that might cause it) but the fact that the statistics arent accurate/wrong.