performance Code-Behind vs. Class File

I was wondering which of these two is better from the aspect of performance.

I was thinking that possibly Class files stored in App_Code works faster because they are sort of pre-compiled but i am not 100% sure.

Specifically i am overriding onInit event on each page using some functions that i am not certain where to place.


Not that i complaint on the speed but i want to be sure that i am doing the right thing.


Thanks

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