Why is throwing exceptions so slow?
They are telling us not to use exceptions to control flow of our programs because throwing exceptions is slow. I have never heard any explanation why is throwing exceptions so slow.
So the question is:
What is the mechanism of throwing exceptions and what are particular operations involved which may have performance impact?
Some clarification: I would like to hear what extra work is need by operation system to handle throwing exceptions. Is there some switching between user and kernel mode which are that costly? Or maybe constructing exception object is costly? Or maybe there is something with switching program flow what I am missing? My question is programming language agnostic (I hope so, but prove me wrong). However If you need some anchor then I am interest the most in .NET internals related with this topic.
I don't have any issues with exceptions performance. I just would like to understand internals of this mechanism.
Made my question more clear.
First of all, I'm not trying to be critical of anyone here or saying that all .Net programmers are this way. But I'm definitely noticing a trend: .Net programmers seem to avoid exceptions like they're
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