when autovacuum runs , it will freeze the transaction ID (TXID) of the table it's working on.
This statement is incorrect. A table as a whole does not have a txid. Freezing makes it so individual tuples get assigned an always-in-the-past txid. Then, the table can recompute how far away its furthest back txid is from being considered in-the-future. That gap should increase since the furthest away txids were the ones being frozen.
Inserts might get delayed a brief moment if it just happens the page they want to insert onto is presently being worked on. But the odds there seem low.
David J.
