42 lines
1.0 KiB
ReStructuredText
42 lines
1.0 KiB
ReStructuredText
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==================================================================
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Effects of Disabling Interrupts or Pre-Emption on Response Latency
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==================================================================
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Rate Monotonic Scheduling
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=========================
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**Assumption**
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No resource sharing (processes do not share resources, e.g. a hardware
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resource, a queue, or any kind of semaphore blocking or non-blocking
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(busy-waits)).
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Wikipedia “Rate Monotonic Scheduling”
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**Real world**
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We must protect shared resources with locks of some kind. The most aggressive:
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#. Disabling interrupts, and
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#. Disabling pre-emption.
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What are the effects of real-time performance when this assumptions is violated?
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Normal Interrupt Processing
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---------------------------
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.. figure:: normal_interrupt.png
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:align: center
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Effect of Disabling Interrupts
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------------------------------
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.. figure:: disabling_interrupts.png
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:align: center
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Effect of Disabling Pre-emption
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-------------------------------
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.. figure:: disabling_preemption.png
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:align: center
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