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 Post subject: Process Transition
PostPosted: Sat Sep 24, 2005 11:00 pm 
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Joined: Sat Sep 24, 2005 11:00 pm
Posts: 5
Every process has three states

1) Running
2) Ready
3) Blocked

According to Process transition, the following are possible:

Running -> Ready
Running -> Blocked

Blocked -> Ready

Ready -> Running.

Besides all these four transitions, is it possible that each stage has 2 transitions, so that the process transitions are 6 ?


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 Post subject: Re: Process Transition
PostPosted: Sat Sep 24, 2005 11:00 pm 
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Joined: Sat Jun 25, 2005 11:00 pm
Posts: 25
what would this mean?

Blocked -> Running
means a process was blocked for IO or something else, then it moved directly into the processor .. this is no good, not everytime a process gets unblocked it should run, it should wait its turn in the ready queue, or otherwise a process that performs frequent short IOs will monopolize the processor.
But, if the process were unblocked and the ready queue were empty then it would turn immediately into the running state :)
Blocked --> Ready --> Running

Ready -> Blocked
what makes a ready process get blocked? blocking happens due to some course of action done by the process which makes it wait for completion .. usually IO

have i answered your question?


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 Post subject: Re: Process Transition
PostPosted: Sat Sep 24, 2005 11:00 pm 
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Joined: Sat Sep 24, 2005 11:00 pm
Posts: 5
Yes, Now I figured out the two missing states. Thankx for the explanation.


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