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Risposte Compito di Sistemi Operativi, 16/01/2001

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

 

P1	P4	P1	P3	P4	P2	P1	P5	P3	P2	P1	P5	P3	P5
0-6ms	6-12	12-18	18-24	24-26	26-32	32-38	38-44	44-50	50-51	51-53	53-59	59-60	60-61

                Tempo medio d'attesa: 146/5
                Turn Around medio: 207/5=36

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9.  
1. ALGORITMO LRU


Pagina Riferita

 

	10	11	6	9	12	3	6	11	10	12	3	9	0	5	2	1	3	9	5	0
0	10	10	10	10	10	3	3	3	3	3	3	3	3	3	3	1	1	1	1	1
1		11	11	11	11	11	11	11	11	11	11	11	0	0	0	0	0	9	9	9
2			6	6	6	6	6	6	6	6	6	9	9	9	9	9	3	3	3	3
3				9	9	9	9	9	10	10	10	10	10	5	5	5	5	5	5	5
4					12	12	12	12	12	12	12	12	12	12	2	2	2	2	2	0
	P	P	P	P	P	P			P			P	P	P	P	P	P	P		P

                        5 + 10 = 15 page fault
 

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2. ALGORITMO SECOND CHANCE

 

	10	11	6	9	12	3	6	11	10	12	3	9	0	5	2	1	3	9	5	0
0	101	101	101	101	101	31	31	31	30	30	31	30	30	30	21	20	20	20	20	01
1		111	111	111	111	110	110	111	110	110	110	91	90	90	90	90	31	30	30	30
2			61	61	61	60	61	61	60	60	60	60	01	00	00	00	00	91	91	90
3				91	91	90	90	90	101	101	101	100	100	100	100	11	10	10	10	10
4					121	120	120	120	120	121	121	120	120	51	50	50	50	50	51	50
	P	P	P	P	P	P			P			P	P	P	P	P	P	P		P

                        5 + 10 = 15 page fault

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