Depending on the speed of the host computer, it should not be more than a couple milliseconds.
Wrong. This is expensive process. Some transactions have very many inputs and SIGOPs.
Verifying them takes much more time even with secp265k1 lib
OK, mr smart ass, let me rephrase.
If the transaction has less than 30 single-signature inputs, verifying it should not
* take more than a couple milliseconds, on a $100+ CPU with secp265k1 lib.
Feeling better now?
* - by
should not I mean that you haven't fucked up your code and it's aspiring to be optimal (e.g. by using parallel threads or not fetching the inputs from some slow database).