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Re: UpTime() in IOKit ?

Hi Markus,

> We use to do polling with a timeout of some hundreds of microseconds.
> With a loop with IOSleep or IODelay inside we lose performance.
>
> What do you think ?

IODelay would be bad, yes.

IOSleep would be reasonable if your hardware or driver is doing nothing
else in the meantime.

Otherwise, add an IOTimerEventSource to your work loop to schedule a
callback at a later time.

Dan

On Monday, February 11, 2002, at 12:25 PM, Markus Bollinger wrote:

> Hi Garth!
>
> During the protocol with our card we have to wait on some bits in one
> of the
> cards registers.
> We use to do polling with a timeout of some hundreds of microseconds.
> With a loop with IOSleep or IODelay inside we lose performance.
>
> What do you think ?
>
>
> ----- Original Message -----
> From: "Garth Cummings" <email@hidden>
> To: "Markus Bollinger" <email@hidden>
> Cc: <email@hidden>
> Sent: Monday, February 11, 2002 6:14 PM
> Subject: Re: UpTime() in IOKit ?
>
>
>> Hi Markus,
>>
>> Before answering this, could you please provide more context on what
>> you
>> need to poll? Polling is strongly discouraged on Mac OS X since it
>> wastes CPU cycles that could be used to do real work for the user.
>>
>> Thanks,
>> --gc
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References: 
 >Re: UpTime() in IOKit ? (From: "Markus Bollinger" <email@hidden>)



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