CPU SCHEDULING Algorithms

• Usage
• FCFS (First-Come, First-Served)
• SJF (Shortest Job First)
• PSJF (Preemptive Shortest Job First)
• RR (Round-Robin)
• Linux Kernel add Syscall (Ubuntu)

Usage

$ make                                       // compile all program
$ sudo ./time                                // calaulate the period of a time unit
$ sudo ./scheduler < data/FCFS_1.txt         // test the first data of FCFS
$ ./calc < data/FCFS_1.txt                   // calculate the the preiod of the first data of FCFS
$ sudo sh time.sh                            // calculate the period of all ideal cases and real cases
$ python ganttChart_plot.py                  // plot the gantt chart of all scheduling algorithms
$ 

FCFS

FCFS_1

Process	Arrive time	Burst time
P1	0	1000
P2	0	1000
P3	0	1000
P4	0	1000
P5	0	1000

FCFS_2

Process	Arrive time	Burst time
P1	0	80000
P2	100	5000
P3	200	1000
P4	300	1000

FCFS_3

Process	Arrive time	Burst time
P1	0	8000
P2	200	5000
P3	300	3000
P4	400	1000
P5	500	1000
P6	500	1000
P7	600	4000

FCFS_4

Process	Arrive time	Burst time
P1	0	2000
P2	500	500
P3	500	200
P4	1500	500

FCFS_5

Process	Arrive time	Burst time
P1	0	8000
P2	200	5000
P3	200	3000
P4	400	1000
P5	400	1000
P6	600	1000
P7	600	4000

SJF

SJF_1

Process	Arrive time	Burst time
P1	0	5000
P2	0	2500
P3	200	1000
P4	300	2000

SJF_2

Process	Arrive time	Burst time
P1	100	100
P2	100	4000
P3	200	200
P4	200	4000
P5	200	7000

SJF_3

Process	Arrive time	Burst time
P1	100	3000
P2	100	5000
P3	100	7000
P4	200	10
P5	200	10
P6	300	4000
P7	400	4000
P8	500	9000

SJF_4

Process	Arrive time	Burst time
P1	0	3000
P2	1000	1000
P3	2000	4000
P4	5000	2000
P5	7000	1000

SJF_5

Process	Arrive time	Burst time
P1	0	2000
P2	500	500
P3	1000	500
P4	1500	500

PSJF

PSJF_1

Process	Arrive time	Burst time
P1	0	5000
P2	0	2500
P3	200	1000
P4	300	2000

PSJF_2

Process	Arrive time	Burst time
P1	0	3000
P2	1000	1000
P3	2000	4000
P4	5000	2000
P5	7000	1000

PSJF_3

Process	Arrive time	Burst time
P1	0	2000
P2	500	500
P3	1000	500
P4	1500	500

PSJF_4

Process	Arrive time	Burst time
P1	0	7000
P2	0	2000
P3	100	1000
P4	200	4000

PSJF_5

Process	Arrive time	Burst time
P1	100	100
P2	100	4000
P3	200	200
P4	200	5000
P5	200	7000

RR

RR_1

Process	Arrive time	Burst time
P1	0	1000
P2	0	1000
P3	0	1000
P4	0	1000
P5	0	1000

RR_2

Process	Arrive time	Burst time
P1	600	4000
P2	800	5000

RR_3

Process	Arrive time	Burst time
P1	1200	5000
P2	2400	4000
P3	3600	3000
P4	4800	7000
P5	5200	6000
P6	5800	5000

RR_4

Process	Arrive time	Burst time
P1	0	8000
P2	200	5000
P3	300	3000
P4	400	1000
P5	500	1000
P6	500	1000
P7	600	4000

RR_5

Process	Arrive time	Burst time
P1	0	8000
P2	200	5000
P3	200	3000
P4	400	1000
P5	400	1000
P6	600	1000
P7	600	4000

Linux Kernel

• linux-4.10.13

Reference

https://sls.weco.net/node/21325

https://github.com/wangyenjen/OS-Project-1

https://blog.kaibro.tw/2016/11/07/Linux-Kernel%E7%B7%A8%E8%AD%AF-Ubuntu/