Measuring execution time with Date()

Question

I want to compare to different implementation of a function:

let start1 = Date()
_ = funcImplA()   
let end1 = Date()

let start2 = Date()
_ = funcImplB()
let end2 = Date()

let time1 = end1.timeIntervalSince(start1)
let time2 = end2.timeIntervalSince(start2)
print("ImplA = \(time1 ), ImplB = \(time2)")

The results I'm getting is that the first measure is always slower than the second one ( time1 > time2 ). Meaning that if I'm switching between the calls, fist measure funcImplB() and then funcImplA , I'm still get that time1 > time2 . What might be the reason?

Answer 1

You could test this in unit tests and use measure block

Please also consider running this on real device, not simulator