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24 lines
859 B
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24 lines
859 B
Plaintext
This readme refers to the file thr-mach.c.
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Under mach, thread priorities are kinda strange-- any given thread has
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a MAXIMUM priority and a BASE priority. The BASE priority is the
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current priority of the thread and the MAXIMUM is the maximum possible
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priority the thread can assume. The developer can lower, but never
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raise the maximum priority.
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The gcc concept of thread priorities is that they run at one of three
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levels; interactive, background, and low.
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Under mach, this is translated to:
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interactive -- set priority to maximum
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background -- set priority to 2/3 of maximum
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low -- set priority to 1/3 of maximum
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This means that it is possible for a thread with the priority of
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interactive to actually run at a lower priority than another thread
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with a background, or even low, priority if the developer has modified
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the maximum priority.
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