Benchmarking code with a StopWatch or similar

Question

I'm trying to use Go package "time" to benchmark a function in my program. Been searching around, and people seem to use time.NanoSeconds() - but I think this function is no longer in the time package?

What I need is an easy way to start and stop a timer, and print out the value.

Answer 1

Use the existing functionality of the testing package inside your *_test.go:

func BenchmarkMyFunc(b *testing.B) {
    for i := 0; i < b.N; i++ {
        myBecnhmarkedFunction()
    }
}

and invoke go test -bench RE (RE is a regexp to select the benches, like B as it means *B*) typically inside the package/tool directory

Or explicitly from any place in your code - use the Benchmark function.