There is almost certainly a performance and battery life hit. Each pointer dereference will trigger a lookup in the MTE tag table, and a comparison between the

There is almost certainly a performance and battery life hit. Each pointer dereference will trigger a lookup in the MTE tag table, and a comparison between the pointer's tag and the table's tag. So you have a decently sized chunk of RAM set aside for the tag table, more memory bandwidth used up by table lookups, and the cost of the actual tag checks.