CSE 120 Lecture Notes - Lecture 10: Page Table, Demand Paging, Segmentation Fault
Document Summary
The only time it will not fit is when you have no more physical memory! If my pages are framed as powers of 2 , then the physical address can be in the form (f,i) Where frame is the higher order bits. Page table - assume 1 pt per process. V: valid bit (information in the table is good) Location in memory given by: (i. e. where to find this page table) Page table base register ( ptbr) - in hardware. Page table size register ( ptsr) - also in hardware. Physical address: = frame of p + offset i. I. e. p is valid to index into the pt by comparing to ptsr ( is p < ptsr? ) Extract the frame # in the entry. Check permissions (can we write into the entry?) frame f. N bits for the page # 2 n entries in pt. Need to know: offset i the size of physical memory.