Calculating pending order expiration : Datetime vs Timer

[Diane Minshew]

Would if be better to use datetime and calculate the future date of expiration or count using a timer to delete the pending order?

[Alain Verleyen]

wehsnim:

Would if be better to use datetime and calculate the future date of expiration or count using a timer to delete the pending order?

An expiration date is more reliable as it's executed on server side.