Re: fixed time slices?

AFAIR this is a hardware dependent value. The thread schedule in all NT
based OSes has always behaved this way.

"Don Burn" <burn@xxxxxxxxxxxxxxxxxxxx> wrote in message
news:%23Jeb0DEtHHA.2004@xxxxxxxxxxxxxxxxxxxxxxx
The minimum wait interval unless you explicitly change it is 10ms plus
some overhead for getting in and out of the kernel, etc. So 15ms is about
what I would expect. Use the multimedia timers if you want to go below
10ms.


--
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr
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"Jan Bruns" <testzugang_janbruns@xxxxxxxx> wrote in message
news:467ada27$0$6441$9b4e6d93@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hallo.

I've noticed that my XP computer seems to handle time-slices
difrent from what I think it used to.

The rule I remember it should be is like defined in the SDK:

| If a higher-priority thread becomes available to run, the system
| ceases to execute the lower-priority thread (without allowing it
| to finish using its time slice), and assigns a full time slice
| to the higher-priority thread.

But now, if I create a process/thread that does nothing but this:

repeat
for i := 0 to n do begin
setWaitableTimer(timer,...);
waitForSingleObjectEx(timer,...);
end;
write_time;
unitl false;


it turns out that the minimum wait intervall seems to be 15ms,
and other timer-inveralls are rounded up to something near a
multiple of that minimum wait intervall, even if I set a
high priority to that process and the system is otherwise idle.

The same thing happens using sleep().

What's going on here?

Gruss

Jan Bruns






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Relevant Pages

  • fixed time slices?
    ... | If a higher-priority thread becomes available to run, ... | to finish using its time slice), and assigns a full time slice ... if I create a process/thread that does nothing but this: ... it turns out that the minimum wait intervall seems to be 15ms, ...
    (microsoft.public.win32.programmer.kernel)
  • Re: fixed time slices?
    ... | If a higher-priority thread becomes available to run, ... | to finish using its time slice), and assigns a full time slice ... if I create a process/thread that does nothing but this: ... it turns out that the minimum wait intervall seems to be 15ms, ...
    (microsoft.public.win32.programmer.kernel)