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Risposte Compito di Sistemi Operativi, 30/01/2001

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1. d,g
2. c,h
3. c,e,f,g,h
4. a,d
5. d,g
6.  
7.  
8. Politica Round Robin

 

P1	P3	P1	P4	P3	P2	P1	P5	P4	P2	P1	P5	P4	P5
3-9ms	9-15	15-21	21-27	27-29	29-35	35-41	41-47	47-53	53-54	54-56	56-62	62-64	64-65

                Tempo medio d'attesa: 147/5
                Turn Around medio: 209/5

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9.  
1. ALGORITMO LRU


Pagina Riferita

 

	1	12	3	2	0	10	12	3	9	0	5	2	1	3	9	5	0	9	0	2
0	1	1	1	1	1	10	10	10	10	10	5	5	5	5	5	5	5	5	5	5
1		12	12	12	12	12	12	12	12	12	12	2	2	2	2	2	0	0	0	0
2			3	3	3	3	3	3	3	3	3	3	1	1	1	1	1	1	1	2
3				2	2	2	2	2	9	9	9	9	9	3	3	3	3	3	3	3
4					0	0	0	0	0	0	0	0	0	0	9	9	9	9	9	9
	P	P	P	P	P	P			P		P	P	P	P	P		P			P

                        5 + 9 = 14 page fault
 

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2. ALGORITMO SECOND CHANCE


TurnoMS = 4

 

	1	12	3	2	0	10	12	3	9	0	5	2	1	3	9	5	0	9	0	2
0	11	11	11	11	11	101	101	101	101	101	100	100	100	31	31	31	30	30	30	30
1		121	121	121	121	120	121	121	120	51	51	51	51	51	51	01	01	01	01	01
2			31	31	31	30	30	31	30	30	30	21	21	21	21	21	20	20	20	21
3				21	21	20	20	20	91	91	91	91	90	90	91	91	90	91	91	91
4					01	00	00	00	00	01	00	00	11	11	11	11	10	10	10	10
	P	P	P	P	P	P			P		P	P	P	P			P

                        5 + 7 = 12 page fault

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