KEEP_RESTORE_POINTS <N> allows the server to maintain information about the last N Restore Points. This is somewhat like the KEEP_LOGS keyword. The last N Restore Points are referred to as the "Active Restore Points." It is possible to set N to zero which means there will be no Active Restore Points. If there are no Active Restore Points, then automatic recovery cannot rollback to a quiet transaction state. The list of Active Restore Points is stored in each checkpoint. In the case of a Checkpoint Restore Point, the checkpoint includes itself as the last Active Restore Point.
Note: When N is greater than zero, the server automatically maintains the transactions logs necessary to ensure that a rollback to any of the Active Restore Points is possible. However, KEEP_RESTORE_POINTS does not affect the existence of the Restore Point files. These files are quite small (128 bytes), and are not deleted by the server.