import time

def compute_resolution(func):
    resolution = None
    points = 0
    timeout = time.monotonic() + 1.0
    previous = func()
    while time.monotonic() < timeout or points < 3:
        for loop in range(10):
            t1 = func()
            t2 = func()
            dt = t2 - t1
            if 0 < dt:
                break
        else:
            dt = t2 - previous
            if dt <= 0.0:
                continue
        if resolution is not None:
            resolution = min(resolution, dt)
        else:
            resolution = dt
        points += 1
        previous = func()
    return resolution

def format_duration(dt):
    if dt >= 1e-3:
        return "%.0f ms" % (dt * 1e3)
    if dt >= 1e-6:
        return "%.0f us" % (dt * 1e6)
    else:
        return "%.0f ns" % (dt * 1e9)

def test_clock(name, func):
    print("%s:" % name)
    resolution = compute_resolution(func)
    print("- efffective resolution: %s" % format_duration(resolution))


clocks = ['time', 'perf_counter', 'monotonic']
for name in clocks:
    func = getattr(time, name)
    test_clock("%s()" % name, func)
    info = time.get_clock_info(name)
    print("- implementation: %s" % info.implementation)
    print("- resolution: %s" % format_duration(info.resolution))
    print()