Hi,
We've had bugs in pg_upgrade where post-upgrade xid horizons weren't correctly
set. We've had bugs were indexes were corrupted during replay.
The latter can be caught by wal_consistency_checking - but that's pretty
expensive.
It seems $subject would have a chance of catching some of these bugs, as well
as exposing amcheck to a database with a bit more varied content?
Depending on the cost it might make sense to do this optionally, via
PG_TEST_EXTRA?
Greetings,
Andres Freund