Outline 2/11/98

• Last time: Working Set, WSClock, PPF, page sizes
• Any questions?
• Administrative: Homework 3 is on webpage
• Today's Objective:
• Finish up memory management issues (page size, alternative page tables)
• Review for midterm

Page Table Space

• Assume a 32 bit address space, 12 bit offsets, 4Kbyte pages, 2**20 pages, each with a 4 byte PTE
• Each process's page table is 4Mbytes
• Solutions:
• Page the page table -2-level paging
• Inverted page table with SW TLB miss handling.

SW TLB & Inverted PT

• Large enough TLBs yield very low miss rates
• miss can be handled in SW
• allows freedom in choosing Page Table structure
• Inverted page table
• one entry for each frame (not page) - resident pages only
• hash virtual page #, match with contents