Solución de los ejercicios de memoria virtual
De Wiki de Sistemas Operativos
NRU
En caso de empate, se emplea LRU.
accesos a páginas | r | r | w | r | r | r | r | w | w | w | r | r | ------------------------------------------------------------------------------------------------- | 1 | 3 | 3 | 3 | 4 | 5 | 1 | 2 | 5 | 1 | 3 | 4 | --------------------------------------------------------------------------------------------------------- | 1 | 1 | = | = | = | = | = | = | = | = | = | = | = | | |-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------| | R | M | 1 | 0 | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | --------------------------------------------------------------------------------------------------------- marcos | 2 | | 3 | 3 | = | = | = | = | = | = | = | = | = | | |-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------| | R | M | | | 1 | 0 | 1 | 1 | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | = | --------------------------------------------------------------------------------------------------------- | 3 | | | | | 4 | = | = | 2 | = | = | = | 4 | | |-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------| | R | M | | | | | | | | | 1 | 0 | = | = | = | = | 1 | 1 | = | = | = | = | = | = | 1 | 0 | --------------------------------------------------------------------------------------------------------- | 4 | | | | | | 5 | = | = | 5 | = | = | = | | |-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------|-------| | R | M | | | | | | | | | | | 1 | 0 | = | = | = | = | 1 | 1 | = | = | = | = | = | = | --------------------------------------------------------------------------------------------------------- fallo | X | X | | | X | X | | X | | | | X | página ------------------------------------------------------------------------------------------------- tiempo -> 6 talla de fallos de página = ------ = 0,5 12
Sustitución por envejecimiento
Periodo de 4, registro R de 3 bits, desempate: LRU
_________________accesos a página__________________ |_2_|_3_|_3_|_1_||_4_|_5_|_4_|_1_||_5_|_2_|_3_|_4_| ====================================================== 1 | 2 | = | = | = || 2 | 5 | = | = || 5 | = | = | = | |100| = | = | = ||010|100| = | = ||110| = | = | = | m---|---|---|---|---||---|---|---|---||---|---|---|---| a 2 | | 3 | = | = || 3 | = | = | = || 3 | 2 | = | = | r | |100| = | = ||010| = | = | = ||001|100| = | = | c---|---|---|---|---||---|---|---|---||---|---|---|---| o 3 | | | | 1 || 1 | = | = | 1 || 1 | = | = | 4 | s | | | |100||010| = | = |110||011| = | = |100| ---|---|---|---|---||---|---|---|---||---|---|---|---| 4 | | | | || 4 | = | = | = || 4 | = | 3 | = | | | | | ||100| = | = | = ||010| = |100| = | --------------------------------------------------------> t x x x x x x x x 8 tasa fallos pág = ---- 12