Multistack and dynamic scheduling

Forum related to ERIKA Enterprise and RT-Druid version 2

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Nautilus85

Multistack and dynamic scheduling

Post by Nautilus85 »

Hello

can anyone explain what a multistack is and what dynamic scheduling is because it stands in the erika brochoure.

best regards
paolo.gai
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Joined: Thu Dec 07, 2006 12:11 pm

Re:Multistack and dynamic scheduling

Post by paolo.gai »

Hi,

ERIKA Enterprise has been designed with low code and data footprint in mind.

To do that, ERIKA implements immediate priority ceiling, stack resource policy and preemption thresholds.

For that reason, ERIKA provides two ways of operation:
- Monostack : all the threads share the same stack, no blocking primitives are allowed.
- Multistack : the system handles different stacks, typically one for each extended task, one for ISRs, and one for all the absic tasks.

The idea is that a monostack configuration is more efficient compared with a multistack configuration, in terms of footprint (from around 1100 bytes to 800), registers to be saved (monstack configuration does not save the registers for the CPU context), overhead (1-4 usec per call).

With dynamic scheduling we intend the fact that ERIKA implements an optimized version of Earliest Deadline First (EDF).

I hope this helps...

Paolo
Nautilus85

Re:Multistack and dynamic scheduling

Post by Nautilus85 »

hey
thank`s that helps :)
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