On fast hardware the SLEEP statement do not act correctly

[dbenoit]

Hello,

I noticed on several installations that the Sleep statment causes CPU issues when the customer hardware is a powerfull one.

For example: 

While 1

    Sleep(5000)

Wend

Shall cost 0% CPU

But is the hardware is fast the Sleep(5000) costs 3 % CPU when included into a loop.

So, if 50 users start this script concurrent it overkill the CPU (which is not good of course).

In such cases, the workaround I am using is to set a much longuer delay fo such specific case, but this is not a good solution

because the script behavior is unpredictable.

Can you help me on that specific problem?

Kind regards

Dominique Benoit

 

 

[BrewManNH]

That would never cause a CPU to use 3% of anything, you're just sleeping the script for 5 seconds, which uses no CPU resources. Even on a fast computer that wouldn't cause a 3% usage, whatever a fast computer means to you.

[Turkishuser]

Autoit Script  have this problem at

My Patch

CPU %0
 

try it

$dll=DLlOpen("ntdll.dll")
while 1

_HighPrecisionSleep(100000,$dll)
WEnd



Func _HighPrecisionSleep($iMicroSeconds,$hDll=False)
    Local $hStruct, $bLoaded
    If Not $hDll Then
        $hDll=DllOpen("ntdll.dll")
        $bLoaded=True
    EndIf
    $hStruct=DllStructCreate("int64 time;")
    DllStructSetData($hStruct,"time",-1*($iMicroSeconds*10))
    DllCall($hDll,"dword","ZwDelayExecution","int",0,"ptr",DllStructGetPtr($hStruct))
    If $bLoaded Then DllClose($hDll)
EndFunc

Edited October 8, 2013 by Turkishuser

[BrewManNH]

Try it with a Sleep(100), you'll see the same results. There's no reason to use a timer like that just to get the script to sleep for a few milliseconds to limit CPU activity.

[dbenoit]

Hello,

I review my code.

In fact within the loop, of course I am doing something.

I had If ProcessExists($pid) Then ExitLoop

 

While 1

    If ProcessExists($pid) Then ExitLoop

    Sleep(5000)

Wend

 

I have replace it by 

 

$exitloop = False

While 1

 

$list = ProcessList()          ; hopping that this will use less CPU

   For $I = 1 To $list[0][0]

       If $pid = $list[$I][1] Then 

            $exitloop = True

            ExitLoop

       EndIf

   Next

    Sleep(5000)

If $exitloop the ExitLoop

Wend

 

So I feel that the point is the CPU usage of ProcessExists statement

We 50 concurrent script running concurrently you load the CPU by checking the processes every 5 seconds per user

I hope that the processlist statement will use less CPU

I will know it tomorrow

Thank you for you inputs

I do appreciate

Dominique Benoit

[KaFu]

Would it be possible to replace the ProcessExists() call with a WinExists() call? I've done this replacement in the past because I noticed that the ProcessExists() calls produce tons and tons of paging errors.