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Un-suspending the scheduler is slow?

Posted by Alain Mouette on August 11, 2009
Hi Richard,

in FreeRTOS manual it says: "but resuming (or 'un-suspending') the scheduler has the potential of being a potentialy lengthy operation..."

Could you elaborate on this, please? Am I right in assuming that it can be lengthy in case of a task-switch? Would it not be a time that had to be lost anyway?


RE: Un-suspending the scheduler is slow?

Posted by Dave on August 11, 2009
Tick interrupts that occur while the scheduler is suspended are held pending and instead processed when the scheduler is un suspended. I think this is what it is referring to. It should not really be a long operation unless the scheduler has been suspended for a long time and there are a lot of pending ticks to process, but that would be bad practice anyway. The scheduler should only be suspended for very short periods.

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