Re: Cooperative multitasking OS-??

On 2007-11-30, ssubbarayan <ssubba@xxxxxxxxx> wrote:

Sorry if this sounds novice.I would like to really understand
whats meant by Cooperative multitasking OS?

It means that a task runs until it explicitly and voluntarily
yeilds.

From what I understood going through the
discussion,Cooperative to me looks like FIFO scheduling
mechanism.

No. The scheduling algorithm can be anything.

Wikipedia IIRC says,Cooperative multitasking systems existed during
pre win9xOS days and non existant almost in current scenerio.Is this
true?

Yes.

How different is this Cooperative system from roundrobin or FIFO?

You're confusing the scheduling method that decides
who to run next with the method that decides when to switch to
the next task. The two are more-or-less independant.

How does the OS kernel decide which task/process to promote at
any point of time?

Irrelevent to the question of cooperative vs. pre-emptive
multitasking. "Cooperative" refers to the decision on _when_
to switch to the next task. It has nothing to do with deciding
_who_ the next task is going to be.

What sort of applications need cooperative functionality?

Cooperative multi-tasking can have less overhead than
pre-emptive multt-tasking, so it's ofen used in more resource
limited situations.

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