Previously i've reported BUG # 16620. But there is no answer on my new mails, so i have to open this new report.
Currently we have to restart postgresql 12.3 every 5-7 days to make it work properly on 5 terabyte cluster with ~ 50 databases. The problem is that autovacuum stops to process certain databases and cycles on the only one... Until we restart cluster.
We've made a trigger and now detecting very situation when it happen. And it happen every 5-7 day. So postgresql is loosing actual statistic, we see not effecttive plans, we need to restart postgresql and also we have to run vacuum full explicitly frequently. So this all is huge headake.
please, check open transactions. Restart, close all sessions, all transactions.
Did you check pg_stat_activity if there are some sessions in state "idle in transactions" before restart?
