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Re: IOProc limitations
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Re: IOProc limitations

on 5/30/01 9:24 PM, Jeff Moore at email@hidden wrote:

> The HAL doesn't touch other thread's priorities. It's IOThreads are Mach
> real-time threads. As such, they are the highest priority threads in the
> system, capable of pre-empting just about everything.

I had thought that OSX kernel did priority inversion, so that any thread
holding a mutex required by a high priority thread would get bumped to the
same priority. (not by the HAL but by the kernel scheduler.)


> As a general rule, it is a really bad idea to stall the IOThread by waiting
> on a mutex or something like that. You'll really hose your timing if the

OK. But how do you sync your threads? If you cannot use a mutex then you
cannot implement a semaphore or a condition. It would seem that you would
only have polling to fall back on to check the ioproc's progress.


--- james mccartney email@hidden <http://www.audiosynth.com>
SuperCollider - a real time synthesis programming language for the PowerMac.
<ftp://www.audiosynth.com/pub/updates/SC2.2.10.sea.hqx>

References: 
 >Re: IOProc limitations (From: Jeff Moore <email@hidden>)



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