CDA3101 Test 3 Topics
Below is an outline of the major topics that may appear on the final test. Make sure you are comfortable with all of the points below, as well as the exercises done in class and in the review problem set. Also make sure that you are comfortable with the material of the second project.
There will be a bonus question on the test pertaining to the previous unit, specifically pipelining.
• Lecture 11: Memory Hierarchy
– Desirable properties of memory: quick access and large size.
∗ Why can’t we optimize both at the same time?
∗ How does a memory hierarchy simulate having large amounts of fast memory?
– Temporal and Spatial Locality
∗ What are they?
∗ How are they exploited in a memory hierarchy?
– General Memory Hierarchy Concepts
∗ Multiple levels of memory with varying speed and size.
∗ All data found in one level is found in the next lower level.
– Four technologies used in memory.
– Differences between SRAM and DRAM.
– Memory Hierarchy Terms
∗ Hit, Miss
∗ Miss time, Miss Penalty
∗ Hit Rate, Miss Rate
∗ Block
– Caches
∗ Direct-Mapped, Set Associative, Fully Associative
∗ Offset, Index, Tag – know how to calculate bit width and find values.
∗ Relationships between cache attributes (e.g. block size and miss rate).
∗ Block replacement strategies (random and LRU).
∗ Write-through vs. Write-back.
∗ Write allocation vs. No write allocate.
∗ Cache miss categories: compulsory, capacity, and conflict.
· Be able to define and describe these.
· How can these be reduced?
∗ Techniques for reducing miss penalites: critical word first and early restart.
∗ Multi-level caches.
∗ General techniques for improving cache performance (and their drawbacks).
– Examples from class and exercises posted.
• Lecture 12: Virtual Memory
– What are the two motivations for virtual memory?
1

– General Virtual Memory Concepts
∗ Each process is compiled into its own virtual address space.
∗ Virtual addresses are translated into physical addresses at run time.
– Virtual Memory Terms: page, page fault.
– Partitioning of virtual and physical address.
– Process of translation from virtual to physical address.
– Common design choices for virtual memory systems.
– Page table concepts.
– TLB concepts.
– Multiprogramming with virtual memory.
– Examples from class and exercises posted.
• Lecture 13: I/O
– Magnetic Disk Organization concepts.
– Know steps for accessing data on disk.
– Be able to calculate average access time for disk configuration.
– What is RAID? What are the goals of implementing RAID?
∗ Improves performance, availability, and provides redundancy.
– Be able to describe/diagram RAID 0 and RAID 1.
2