Tutorial Week 10

Questions

Virtual Memory

Q1: What effect does increasing the page size have?


Q2: Why is demand paging generally more prevalent than pre-paging?


Q3: Describe four replacement policies and compare them.

Q4: Translate the following virtual addresses to Physical Addresses using the TLB. The system is a R3000. Indicate if the page is mapped, and if so if its read-only or read/write.

The EntryHi register currently contains 0x00000200.

The virtual addresses are 0x00028123, 0x0008a7eb, 0x0005cfff,0x0001c642, 0x0005b888, 0x00034000.

TLB
EntryHiEntryLo
0x000282000x0063f400
0x000342000x001fc600
0x0005b2000x002af200
0x0008a1000x00145600
0x0005c1000x006a8700
0x0001c2000x00a97600

Q5: What is thrashing? How can it be detected? What can be done to combat it?

Q6: Of the two page table types covered in lectures, which one is most appropriate for a virtual address spaces that are sparsely populated (e.g. many single pages scattered through memory)?


Q7: What is temporal and spatial locality?