Question

I’m trying to measure elapsed time using Stopwatch but consistently get times which are lower ~3.1 times than actual elapsed time. I can’t put my finger on why this happens, code is dead simple. I’ve tried the code on 3 machines and getting same result (although with nearly same hardware and software).

i5-2500k, i5-2500, Windows 7 64 bit, Windows 8 RTM 64 bit

Stopwatch sw = new Stopwatch();
sw.Restart();
DateTime start = DateTime.Now;

for (int i = 0; i < 5; i++)
{
    Thread.Sleep(1000);
}

DateTime end = DateTime.Now;
sw.Stop();

Console.WriteLine("Time passed: " + StringFormatter.ToShortString(sw));
Console.WriteLine("Time passed: " + StringFormatter.ToShortString(end - start));

result is consistently ~3.1 times off.

Time passed: 00:00:01.6347
Time passed: 00:00:05.0600

for 10 sec delays:

Time passed: 00:00:03.2358
Time passed: 00:00:10.0100

Answer 1

Ok, this was stupid. Stopwatch.ElapsedTicks was being used as if it was timespan. Resolution needed to be adjusted for printing logic.