Lecture 20

Learning objectives

After this class, you should be able to:

1. Explain the ideal cache model.
2. Derive the cache complexity of the two simple matrix multiplication algorithms discussed in class, and of the cache aware algorithm discussed in class.
3. Given an algorithm, derive its cache complexity.
4. Given an algorithm that is cache-inefficient, modify it to make it more efficient.

Reading assignment

1. Handout on cache aware and cache oblivious algorithms.

Exercises and review questions

• Questions on current lecture's material
  1. If matrices were stored in column major order, then show two simple algorithms, one which has a cache complexity of theta(n³) and one with cache complexity of theta(n³/L).

• Questions on next lecture's material
  1. None.