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In the following process state transition diagram for a uniprocessor system, assume that there are always some processes in the ready state:

Now consider the following statements:

1. If a process makes a transition D, it would result in another process making transition A immediately.
2. A process $P_2$ in blocked state can make transition E while another process $P_1$ is in running state.
3. The OS uses preemptive scheduling.
4. The OS uses non-preemptive scheduling.

Which of the above statements are TRUE?

1. I and II
2. I and III
3. II and III
4. II and IV
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1. If a process makes a transition D, it would result in another process making transition A immediately. - This is false. It is not said anywhere that one process terminates, another process immediately come into Ready state. It depends on availability of process to run & Long term Scheduler.
2. A process P2 in blocked state can make transition E while another process P2 is in running state. - This is correct. There is no dependency between running process & Process getting out of blocked state.
3. The OS uses preemptive scheduling. :- This is true because we got transition C from Running to Ready.
4. The OS uses non-preemptive scheduling.Well as previous statement is true, this becomes false.

So answer is C) II and III .

answered by Boss (42.4k points)
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0
If CPU uses preemptive scheduling then only option 2 is possible. But nothing is given about that in the question.?
+1
say in case of transition A it is written as Transition B then the statement  "If a process makes a transition D, it would result in another process making transition B immediately"  would be correct ?
0
since the long term scheduler controls the degree of multiprogramming,if one process terminates ,it should create a new process. correct me if i am wrong?

Answer is C :

The reason why option 1 may be false :If the process terminate ; then the Short time scheduler will bring immediately process from ready to run (not from new to ready ) . The process of bringing a process from new to ready is responsibility is job of Long Term Scheduler (which is called not so frequently as compared to Short Time Scheduler . Hence we named it Long Time Scheduler . the decision taken by it stays for a long time )

answered by Active (1.2k points)
It is C.

The option I is not necessarily true.
answered by Boss (19.7k points)