The issue I see is that n_ins_since_vacuum should only reflect the number of newly inserted rows that are eligible for freezing, as described in pgstat_report_vacuum [0]
/* * It is quite possible that a non-aggressive VACUUM ended up skipping * various pages, however, we'll zero the insert counter here regardless. * It's currently used only to track when we need to perform an "insert" * autovacuum, which are mainly intended to freeze newly inserted tuples. * Zeroing this may just mean we'll not try to vacuum the table again * until enough tuples have been inserted to trigger another insert * autovacuum. An anti-wraparound autovacuum will catch any persistent * stragglers.
*/
What work do you believe the word "mainly" does in that paragraph? The presence of the word "mainly" rather than "only" somewhat cuts against your argument that we should only be counting tuples that get inserted without aborting.
