Re: DateTime Ticks/Milliseconds Question (possibly Thread.Sleep () related - ?)

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

The resolution of the system clock isn't 1/1000 second, but rathter something like 1/62 second. There is an interrupt that increases an integer value 62 (?) times a second, this integer value is then converted to a time value when you use DateTime.Now.

Every time you see the time change, the interrupt has increased the integer value by one, and that translates to an increase in time of about 16 ms.

Mr Bounce wrote:
Hi,

Slightly dim question, possibly. I dunno. When i run the following c#:

for (int i = 0; i < 100; i++)
{
System.Diagnostics.Debug.WriteLine
(DateTime.Now.Millisecond.ToString ());
System.Threading.Thread.Sleep (1);
}

I would expect the output to increment by at least 1 every line (since
I am asking my thread to sleep for 1 millisecond).

The output generated, however, looks like this:

627
409
409
409
424
424
440
440
440
456
456
456
456

(etc)

surely this is impossible?

I also noticed a similar thing when using Ticks instead of Milliseconds

Is there something im missing? I thought maybe it was something i hadnt
encountered before to do with thread scheduling (ie: none others to be
scheduled, so its not sleeping), but if i change the interval to 100ms
there is a visible (and seemigly regular) pause, and the output number
increments by slightly more than 100 each time round.

If anyone can shed some light on this i would be grateful - I'm now
wondering if its something to do with the clock speed of my PC...?

Thanks,

Chris

.

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