Tutorial Week 9

Questions

Memory Management

Q1: Describe internal and external fragmentation.?

Q2: What are the problems with multiprogrammed systems with fixed-partitioning?

Q3: Assume a system protected with base-limit registers. What are the problems with such a protected system (compared to a paged or segmented VM system)?

Q4: A program is to run on a multiprogrammed machine. Describe at which points in time during program development to execution time where addresses within the program can be bound to the actual physical memory it uses for execution? What are the implication of using each of the three binding times?

Q5: Describe four algorithms for allocating regions of contiguous memory, and comment on their properties.


Q6: What is compaction? Why would it be used?


Virtual Memory

Q7: What is swapping?


Q8: What is Paging?


Q9: Why do all virtual memory system page sizes have to be a power of 2? Draw a picture.


Q10: What is a TLB? What is its function?


Q11: Given a two-level page table (in physical memory), what is the average number of physical memory accesses per virtual memory access in the case where the TLB has a 100% miss ratio, and the case of a 95% hit ratio


Q12: What are the two broad categories of events causing page faults? What other event might cause page faults?