> - Full vacuum does not touch XIDs - use freeze or just normal vacuum, Don't think that's right. copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OID

> - Full vacuum does not touch XIDs - use freeze or just normal vacuum, Don't think that's right. copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex, bool verbose, bool *pSwapToastByContent, TransactionId *pFreezeXid, MultiXactId *pCutoffMulti) ... /* * Compute xids used to freeze and weed out dead tuples and multixacts. * Since we're going to rewrite the whole table anyway, there's no reason * not to be aggressive about this. */ vacuum_set_xid_limits(OldHeap, 0, 0, 0, 0, &OldestXmin, &FreezeXid, NULL, &MultiXactCutoff, NULL); /* * FreezeXid will become the table's new relfrozenxid, and that mustn't go * backwards, so take the max. */ if (TransactionIdPrecedes(FreezeXid, OldHeap->rd_rel->relfrozenxid)) FreezeXid = OldHeap->rd_rel->relfrozenxid; i.e. the cutoff is computed in copy_heap_data(). And then in void rewrite_heap_tuple(RewriteState state, HeapTuple old_tuple, HeapTuple new_tuple) { ... /* * While we have our hands on the tuple, we may as well freeze any * eligible xmin or xmax, so that future VACUUM effort can be saved. */ heap_freeze_tuple(new_tuple->t_data, state->rs_freeze_xid, state->rs_cutoff_multi);