Multiprocessing aims that maximum of the CPU should be utilized.Whenever some process is waiting ,at that time cpu is free and os give cpu to some other process.
Almost all cpu resources all scheduled before their use.
Ready queue : A newly arrived process is stored in ready queue from where CPU allocation is done by os to execute the process
PCB stores this ready , wait or active status of process.
The entry of all the PCBs of the current processes is in : Process table
Non Pre-emptive scheduling:
1)process switches from running to wait
2)process terminate
A new process must be executed in non preemptive scheduling.
Pre emptive scheduling:
1-When a process switches from the running state to the ready state (for
example, when an interrupt occurs)
2-When a process switches from the waiting state to the ready state (for
example, at completion of I/0)
Windows 95 onwards and mac uses preemptive scheduling
Almost all cpu resources all scheduled before their use.
Ready queue : A newly arrived process is stored in ready queue from where CPU allocation is done by os to execute the process
PCB stores this ready , wait or active status of process.
The entry of all the PCBs of the current processes is in : Process table
Non Pre-emptive scheduling:
1)process switches from running to wait
2)process terminate
A new process must be executed in non preemptive scheduling.
Pre emptive scheduling:
1-When a process switches from the running state to the ready state (for
example, when an interrupt occurs)
2-When a process switches from the waiting state to the ready state (for
example, at completion of I/0)
Windows 95 onwards and mac uses preemptive scheduling
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