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Re: PlayThru (was: AudioUnit for default input device)
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Re: PlayThru (was: AudioUnit for default input device)

on 11/20/01 11:44 AM, Jeff Moore at email@hidden wrote:

> on 11/20/01 6:03 AM, James McCartney <email@hidden> wrote:
>
>> I've still not heard how we
>> are supposed to guarantee that we do not suffer a page fault in the IOProc.
>
> There is no guarantee that this won't happen. The kernel doesn't provide any
> mechanism in user space to wire down memory.
>
> The good news is that your IOProc should keep the memory pretty hot so the
> likelihood of taking a page fault is pretty low.

I think it might be easily possible for a user to read in a huge sound file
and random access pieces of it in a fashion such that parts of it get paged
out. I suppose I could write a "memory heater" thread to touch all pages of
loaded sample ram periodically. Sounds like a bad kludge compared to the
kext scheme, but at least portable.

> I suppose an enterprising developer could write a kernel extension to give
> them the ability to allocate wired memory. It wouldn't be too difficult I
> imagine. I'm pretty sure the kernel guys would want my head for even
> suggesting this though =)



--- 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: PlayThru (was: AudioUnit for default input device) (From: Jeff Moore <email@hidden>)



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