Converting a non-temporal table into a temporal table is very easy. With two ALTER TABLE statements you get the full temporal table functionality. However, this cannot be completely free. Adding temporal features to a table brings performance overhead in all data modification operations. According to Microsoft, a single update operation against a row in a temporal table is about 30% slower than it would be when the table is non-temporal.

I have performed a simple test where I have updated a different number of rows in a table before it is converted to a temporal table and afterwards. The following graph displays results of this test. For a small amount of rows (<1000), locking, calculating, and inserting data into a history table slows the update down by 50%. Updating 50,000 rows in a temporal table takes about eight times longer than the same operation against the same table when it is implemented as a non-temporal table:

Finally, massive updates (>100K rows) are 10 times slower for temporal tables compared to those against their non-temporal counterparts.