Suspended state in process transition diagram

Question

Which one of the following state transition is not possible?

(A) Blocked to Blocked Suspended

(B) Blocked Suspended to Ready Suspended

(C) Blocked Suspended to Blocked

(D) Ready Suspended to Blocked Suspended

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Doubts:

1. What are suspended states? Ready suspended and blocked suspended?
2. Is there any difference between these: waiting, blocked, suspended?
3. Is any other term also used for these?

Comments

(D) ready suspended to blocked suspended is never possible

1) suspended states are states which resides in secondary disk rather than MM, when the process P1 is in ready state waiting for its execution but suddenly some process P2(with high priority) needs to come in ready queue(MM), and ready queue is full, then P1 will be send to ready suspended state(hard disk), same logic in case of blocked suspended

2) waiting and blocked are same, suspend is discussed above.

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there is uni directional edge from suspend wait -> suspend ready  so D is not possible

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when does the transition from suspended wait to suspended ready occur?

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Just want to know, why we move a process from Wait/Block to Suspend Wait? I mean we can have multiple processes in Wait/Block state for I/O (correct me if I am wrong).

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Wait/Block means they were moved out due I/O request

we suspend a process mainly when some higher priority process comes and space is low, due to suspension the process is moved to SM from MM.

Answer 1

option D is correct.

process go to suspend state if they do not satisfy the requirement/ MM is unable to handle more process due to storage then some of the processes go to suspend state(secondary memory) for the finite amount of time. when the resource is sufficient/space is available in MM they are resume & come back to MM.

Comments

yes @nitish but in the image posted by Hira there is a broken edge fron running to suspended ready.

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@ Manu Thakur ,@ joshi_nitish I apologize. I didn't see it properly(ready/running), running to suspended ready is not correct. I draw the broken edge by mistake. I corrected it as soon as possible. Thanx for pointing it

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Adding to above queries, transition from which state to which state will cause the process to preempt? Is it only from running to ready state, or are there any more state transitions that'll cause preemption? What happens when the process moves from running to wait/block? A new process is transitioned to running state from ready state? Does that count as preemption?