homework 2 sarah diesburg operating systems cop 4610
TRANSCRIPT
![Page 1: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/1.jpg)
Homework 2
Sarah Diesburg
Operating Systems
COP 4610
![Page 2: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/2.jpg)
Why does OS loader set kernel mode? OS needs to run with full privileges
Sets more restrictive user mode bit for user programs
Protects OS from errant user programs
![Page 3: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/3.jpg)
Three Processes
Process A
Process B
Process C
Time
0 100 200 300 400 500 600 700 800
![Page 4: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/4.jpg)
First In, First Out
Process A
Process B
Process C
FIFOTime
0 100 200 300 400 500 600 700 800
BC A
![Page 5: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/5.jpg)
First In, First Out
Process A
Process B
Process C
FIFO
Average response time
= [(300-50) + (500-150) + 0]/3 = 200
Time
0 100 200 300 400 500 600 700 800
BC A
![Page 6: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/6.jpg)
First In, First Out
Process A
Process B
Process C
FIFO
Average wait time
= [(300-50) + (500-150) + 0]/3 = 200
Time
0 100 200 300 400 500 600 700 800
BC A
![Page 7: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/7.jpg)
First In, First Out
Process A
Process B
Process C
FIFO
Average turnaround time
= [(500-50) + (900-150) + (300-0)]/3 = 500
Time
0 100 200 300 400 500 600 700 800
BA BC A
![Page 8: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/8.jpg)
Round Robin (Time slice = 100)
Process A
Process B
Process C
RRTime
0 100 200 300 400 500 600 700 800
C
![Page 9: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/9.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C
![Page 10: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/10.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A
![Page 11: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/11.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A
![Page 12: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/12.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C
![Page 13: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/13.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C
![Page 14: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/14.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B
![Page 15: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/15.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B
![Page 16: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/16.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A
![Page 17: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/17.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A
![Page 18: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/18.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C
![Page 19: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/19.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C
![Page 20: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/20.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C B
![Page 21: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/21.jpg)
Process A
Process B
Process C
RR
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C B
![Page 22: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/22.jpg)
Process A
Process B
Process C
RR
Average response time
= [(100-50) + (300 – 150) + 0]/3 = 66.7
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C B
![Page 23: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/23.jpg)
Process A
Process B
Process C
RR
Average wait time
= {[(100–50) + (400–200)] + [(300–150) + (600–400)]
+ [0 + (200–100) + (500–300)]}/3 = [250 + 350 + 300]/3 = 300
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C B
![Page 24: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/24.jpg)
Process A
Process B
Process CRR
Average turnaround time= [(500 – 50) + (900 – 150) + (600 – 0)]/3 = 600
Round Robin (Time slice = 100)
Time
0 100 200 300 400 500 600 700 800
C A C B A C B
![Page 25: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/25.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C
![Page 26: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/26.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C
![Page 27: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/27.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C A
![Page 28: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/28.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C A
![Page 29: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/29.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C A
![Page 30: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/30.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C A B
![Page 31: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/31.jpg)
Shortest Job Next
Process A
Process B
Process C
SJNTime
0 100 200 300 400 500 600 700 800
C A B
![Page 32: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/32.jpg)
Shortest Job Next
Process A
Process B
Process C
SJN
Average response time
= [(300-50) + (500-150) + 0]/3 = 200
Time
0 100 200 300 400 500 600 700 800
C A B
![Page 33: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/33.jpg)
Shortest Job Next
Process A
Process B
Process C
SJN
Average wait time
= [(300-50) + (500-150) + 0]/3 = 200
Time
0 100 200 300 400 500 600 700 800
C A B
![Page 34: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/34.jpg)
Shortest Job Next
Process A
Process B
Process C
SJN
Average turnaround time
= [(500-50) + (900-150) + (300-0)]/3 = 500
Time
0 100 200 300 400 500 600 700 800
C A B
![Page 35: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/35.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C
![Page 36: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/36.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C
![Page 37: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/37.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C A
![Page 38: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/38.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C A
![Page 39: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/39.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C A C
![Page 40: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/40.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C A C
![Page 41: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/41.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C A C B
![Page 42: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/42.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTFTime
0 100 200 300 400 500 600 700 800
C A C B
![Page 43: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/43.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTF
Average response time
= [0 + (500-150) + 0]/3 = 117
Time
0 100 200 300 400 500 600 700 800
C A C B
![Page 44: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/44.jpg)
Shortest Remaining Time First
Process A
Process B
Process C
SRTF
Average wait time
= [0 + (500 – 150) + (250 – 50)]/3 = 183
Time
0 100 200 300 400 500 600 700 800
C A C B
![Page 45: Homework 2 Sarah Diesburg Operating Systems COP 4610](https://reader030.vdocuments.us/reader030/viewer/2022032518/56649cca5503460f949922a4/html5/thumbnails/45.jpg)
Shortest Remaining Time First
Process A
Process B
Process CSRTF
Average turnaround time= [(250 – 50) + (900 – 150) + (500 – 0)]/3 = 483
Time
0 100 200 300 400 500 600 700 800
C A C B