CPU Scheduling Algorithms (1)

CPU Scheduling Algorithms (1)

 

1) Long Term Scheduler
RAM -> CPU

2) Short Term Scheduler

Disk -> RAM

3) Medium Term Scheduler

if RAM is FULL:

    decide what process changed(swaped?) 

RAM -> Disk

 

context switch

 

various times related to a process

 

1) arrival time

RAM -> CPU arrival time

 

2) burst time (also called execution time)

 

3) completion time

 

4) turn-around time

arrival time to completion time

 => (completion time) - (arrival time)

 

5) waiting time

Turn-around time = (burst time) + (i/o time) + (waiting time)

 

6) response time

later...

 

7) I/O time