Lecture 13

Learning objectives

After this class, you should be able to:

1. Define the prefix operation.
2. Mention applications of parallel prefix.
3. Analyze the time complexity of the simple parallel prefix algorithm and identify potential reasons for poor performance.

Reading assignment

1. Read UIUC Lecture 13, and UIUC Lecture 14 slides 1-7.
2. Chapter 9 of text, sections 9.1 - 9.3.

Exercises and review questions

• Exercises and review questions on current lecture's material
  1. Exercise 9.1.
  2. Why is double buffering needed in the shared memory of the algorithm in figure 9.2. Post an example on the discussion board to show errors that can happen without it.

• Preparation for the next lecture
  1. Discuss situations when work-efficiency is not relevant and situations where it is.
  2. How does an exclusive scan differ from an inclusive scan?

---

Last modified: 19 Feb 2013