Re: PG13 Autovacuum for Insert

Vacuum isn't just used for cleaning up dead rows from updates/deletes. The biggest reason this was likely added was to account for transaction ID exhaustion (aka wraparound). Newly inserted rows still get a new transaction ID and need to be frozen at some point. If vacuum never runs, that never happens until autovacuum_freeze_max_age is reached, which can cause a slightly more expensive autovacuum to run. If many tables all reach that point at the same time, it can cause a higher than usual spike in some pretty heavy vacuuming activity. If normal autovacuum can kick in before that, it can help spread that out better.