Term
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Definition
| a model for asynchronous data flow with buffered communication |
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Term
| properties of kahn process networks |
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Definition
*each node corresponds to one task/process
*communication is via channels
*for any input the output will always be the same
*send is non-blocking
*receive is blocking
*assume infinite buffer size
*KPNs is deterministic |
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Term
| synchronous data flow model |
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Definition
*synchronous message passing on each channel'
*the same number of messages are being sent per unit as are received |
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Term
| why is configurable needed in rtos |
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Definition
no os will fit all needs of a rtos
*config is needed to remobe unised portions of the os, keeping only the necessary software needed for the ES
*also improves efficiency |
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Term
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Definition
*any proc can call an interrupt
*for a standard os this is a huge source of unreliability |
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Term
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Definition
* timing behavior must be predictable
*upper bound on execution time
*os must be fast |
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Term
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Definition
| fast proprietary kernals, kernels designed to be fast, not predictable |
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Term
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Definition
| use of standard os will not work for es |
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Term
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Definition
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Term
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Definition
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Term
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Definition
*preemption is not allowed
*optimal algorithms will leave the processor idle, to finish tasks with earlier deadlines that arrive later
*to run efficiently, future knowledge is needed to make a good schedule |
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Term
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Definition
*periodic
*average unitilization |
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