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Re: When or on what condition does "deschedule" happen?


Hello everyone,

Thank you very much for your answers.
I've almost got it.
I only need one more affirmation from you.

If ThreadA does not finish and enter looping state,then isn't there any
way for ThreadC to resume execution ?

Nope. The highest priority runnable thread always runs. All high priority threads need to finish doing what they are doing before a lower priority threads get to run.

Am I correct in thinking that this policy applys also to bitmap scheduler ?

Masahiro Ariga

My question is last part of Deschedule when ThreadC resumes execution.

Am I correct in assuming that among your conditions, only two conditions
should be fullfiled to make it possible
for ThreadC to resume execution ?
1.When the thread blocks.(How does scheduler recognise this ?)

Blocking calls are part of the OS and the scheduler knows about them.


2.When a thread exits.

If ThreadA does not finish and enter looping state,then isn't there any
way for ThreadC to resume execution ?

Nope. The highest priority runnable thread always runs. All high priority threads need to finish doing what they are doing before a lower priority threads get to run.

Andrew





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