[理工] 作業系統pagetable、轉換位址、pagefault
有一題是這樣問的
The page table shown below is for a system with 16 bit logical and physical
address and with 192 bytes pages.
The reference bit is set to 1 when the page has been referenced.
The page replacement is localized second chance, next victim is page 0,
and the order is from 0 to 7. All numbers are decimal.
Then the process access the following address (in hexadecimal) sequentially,
0x2145, 0x5A13, and 0x78B2.
(a) convert the addresses to physical addresses.
(b) draw the page table after these three memory accesses.
page frame valid/invalid reference bit
0 3 v 1
1 2 v 0
2 0 v 0
3 0 i 0
4 5 v 0
5 6 v 1
6 0 i 0
7 0 i 0
這題是以virtual memory的概念下去處理但是好像又將memory management
的原理全部都含括進來去做logical轉physical位址...
所以只要是invalid加上bit為0的優先當做victim嗎?該怎麼解這題?
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