The CHECKPOINT statement saves time in a subsequent recovery by creating a point at which all modifications to data and log pages are guaranteed to have been written to disk.When we done operation on SQL SERVER that is not committed directly to the database. All operation must be logged in to Transaction Log files after that they should be done on to the main database. Checkpoint are the point which alert SQL Server to save all the data to main database if no check point is there then log files get full we can use Checkpoint command to commit all data in the SQL SERVER. When we stop the SQL Server it will take long time because Checkpoint is also fired.
Checkpoint [ checkpoint_duration ]
When checkpoint_duration is specified, the SQL Server Database Engine attempts to perform the checkpoint within the requested duration. The checkpoint_duration must be an expression of type int, and must be greater than zero. When this parameter is omitted, SQL Server Database Engine automatically adjusts the checkpoint duration to minimize the performance impact on database applications.