Diferencia entre revisiones de «Solución de los ejercicios de memoria virtual»
De Wiki de Sistemas Operativos
(→Sustitución por envejecimiento) |
(→Corrección de ejercicio con NRU (3ª oportunidad)) |
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| Línea 6: | Línea 6: | ||
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | ||
| 1 | = | = | = | = | = | = | = | = | = | = | = | | | 1 | = | = | = | = | = | = | = | = | = | = | = | | ||
| − | Marco 1 | R=1 | = | = | = | = | = | = | | + | Marco 1 | R=1 | = | = | = | = | = | = | R=0 | = | = | = | R=0 | |
| − | | M=0 | = | = | = | = | = | | + | | M=0 | = | = | = | = | = | M=1 | = | = | M=1 | = | M=0 | |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | ||
| − | | | 3 | = | = | = | = | = | = | = | = | = | | + | | | 3 | = | = | = | = | = | = | = | = | = | 4 | |
| − | Marco 2 | | R=1 | = | = | = | = | = | | + | Marco 2 | | R=1 | = | = | = | = | = | R=0 | = | = | R=1 | R=1 | |
| − | | | M=0 | M=1 | = | = | = | = | | + | | | M=0 | M=1 | = | = | = | = | M=0 | = | = | = | M=0 | |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | ||
| − | | | | | | 4 | = | = | 2 | = | = | = | | + | | | | | | 4 | = | = | 2 | = | = | = | 2 | |
| − | Marco 3 | | | | | R=1 | = | = | R=1 | = | = | = | R= | + | Marco 3 | | | | | R=1 | = | = | R=1 | = | = | = | R=0 | |
| | | | | M=0 | = | = | M=1 | = | = | = | M=0 | | | | | | | M=0 | = | = | M=1 | = | = | = | M=0 | | ||
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | ||
| | | | | | 5 | = | = | = | = | = | = | | | | | | | | 5 | = | = | = | = | = | = | | ||
| − | Marco 4 | | | | | | R=1 | = | | + | Marco 4 | | | | | | R=1 | = | R=0 | R=1 | = | = | R=0 | |
| − | | | | | | | M=0 | = | | + | | | | | | | M=0 | = | M=0 | M=1 | = | = | M=0 | |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+ | ||
Fallo | | | | | | | | | | | | | | Fallo | | | | | | | | | | | | | | ||
Revisión del 16:04 20 dic 2016
NRU
Acceso
a 1(R) 3(R) 3(W) 3(R) 4(R) 5(R) 1(R) 2(W) 5(W) 1(W) 3(R) 4(R)
página
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| 1 | = | = | = | = | = | = | = | = | = | = | = |
Marco 1 | R=1 | = | = | = | = | = | = | R=0 | = | = | = | R=0 |
| M=0 | = | = | = | = | = | M=1 | = | = | M=1 | = | M=0 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| | 3 | = | = | = | = | = | = | = | = | = | 4 |
Marco 2 | | R=1 | = | = | = | = | = | R=0 | = | = | R=1 | R=1 |
| | M=0 | M=1 | = | = | = | = | M=0 | = | = | = | M=0 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| | | | | 4 | = | = | 2 | = | = | = | 2 |
Marco 3 | | | | | R=1 | = | = | R=1 | = | = | = | R=0 |
| | | | | M=0 | = | = | M=1 | = | = | = | M=0 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
| | | | | | 5 | = | = | = | = | = | = |
Marco 4 | | | | | | R=1 | = | R=0 | R=1 | = | = | R=0 |
| | | | | | M=0 | = | M=0 | M=1 | = | = | M=0 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Fallo | | | | | | | | | | | | |
de | x | x | | | x | x | | x | | | | x |
página | | | | | | | | | | | | |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Tiempo 1 2 3 4 5 6 7 8 9 10 11 12
nº fallos de página 6
Tasa de fallos de página = --------------------- = ---- = 0,5
nº accesos a páginas 12
Sustitución por envejecimiento
Periodo = 4
Registro R de 3 bits.
En caso de empate = LRU
Acceso
a 2 3 3 1 - 4 5 4 1 - 5 2 3 4
página
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Marco 1 | 2 | = | = | = | = | = | 5 | = | = | = | = | = | = | = |
Bit R | 100 | = | = | = | 010 | = | 100 | = | = | 010 | 110 | = | = | = |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Marco 2 | | 3 | = | = | = | = | = | = | = | = | = | 2 | = | = |
Bit R | | 100 | = | = | 010 | = | = | = | = | 001 | = | 100 | = | = |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Marco 3 | | | | 1 | = | = | = | = | = | = | = | = | = | 4 |
Bit R | | | | 100 | 010 | 010 | = | = | 110 | 011 | = | = | = | 100 |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Marco 4 | | | | | | 4 | = | = | = | = | = | = | 3 | = |
Bit R | | | | | | 100 | = | = | = | 010 | = | = | 100 | = |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Fallo | | | | | | | | | | | | | | |
de | x | x | | x | - | x | x | | | - | | x | x | x |
página | | | | | | | | | | | | | | |
+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
Tiempo 1 2 3 4 - 5 6 7 8 - 9 10 11 12
Periodo 4 3 2 1 0 4 3 2 1 0 4 3 2 1
8
nº fallos de página 8
Tasa de fallos de página = --------------------- = ---- = 0,6666666666666667
nº accesos a páginas 12
