I encountered a problem when using the slowly changing dimension (SCD) in large databases. SCD is easy and fast when it comes to less number of records. therefore I used following mechanism to speed up the process using available SSIS components.
First record set is send through Lookup command. in there we are checking that item is already available with the table.
If yes we are redirecting to UPDARE Command and If not we are redirecting to Insert Command.
But make sure following redirect option (Redirect rows to no match output) is set in the lookup component.