Hi, PG: 9.6.11 OS: CentOS Env: AWS EC2
I've faced the following exceptions in PostgreSQL server log: > could not truncate directory "pg_serial": apparent wraparound Sometimes it repeats every 5 min and the longest period was 40 min. In fact, I can't find any suspicious events happening that periods. pg_wait_sampling didn't catch any events, no long queries (more than 60s), Autovacuum workers or transactions in "idle in transaction" state were in action at this time. The only related I could find in archive is: https://www.postgresql.org/message-id/CACjxUsON4Vya3a6r%3DubwmN-4qTDDfZjuwSzjnL1QjdUc8_gzLw%40mail.gmail.com >You should not see the errors you are reporting nor >the warning I mentioned unless a serializable transaction remains >active long enough for about 1 billion transaction IDs to be >consumed. Database age now is just 18.5 millions of transactions. Server has two standbys (sync and async), hot_standby_feedback is off. Please advice what I can do to find a reason of these exceptions.
