Page 61 - DCAP403_Operating System

Operating System

Notes This state transition is:

Time-Run-Out: Running? Ready.
Dispatch: It occurs when all other processes have had their share and it is time for the fi rst
process to run again
This state transition is:

Dispatch: Ready? Running.
Wakeup: It occurs when the external event for which a process was waiting (such as arrival of
input) happens.

This state transition is:
Wakeup: Blocked? Ready.
Admitted: It occurs when the process is created.
This state transition is:
Admitted: New? Ready.
Exit: It occurs when the process has fi nished execution.

This state transition is:
Exit: Running? Terminated.
Figure 4.4: Process State Transitions

New Terminated
Exit
Admitted
Dispatch
Ready Running

I/O or event I/O or
completion wait event
Blocked

Ready queue
Processor

Blocked queue

54 LOVELY PROFESSIONAL UNIVERSITY