5.10. Parallel Computing

This lesson focuses on parallel and distributed computing.

CSP Framework
Big Idea 4: Computing Systems and Networks (CSN)
Enduring Understanding CSN-2: Parallel and distributed computing leverage multiple computers to more quickly solve complex problems or process large data sets.
Learning Objective CSN-2.A.a: For sequential, parallel, and distributed computing: a. Compare problem solutions. Learning Objective CSN-2.A.b: For sequential, parallel, and distributed computing: b. Determine the efficiency of solutions.
Skill 1.D CSN-2.A.1 CSN-2.A.2 CSN-2.A.3 CSN-2.A.4 CSN-2.A.5 CSN-2.A.6 CSN-2.A.7 Essential Knowledge CSN-2.A.1: Sequential computing is a computational model in which operations are performed in order one at a time. Essential Knowledge CSN-2.A.2: Parallel computing is a computational model where the program is broken into multiple smaller sequential computing operations, some of which are performed simultaneously. Essential Knowledge CSN-2.A.3: Distributed computing is a computational model in which multiple devices are used to run a program. Essential Knowledge CSN-2.A.4: Comparing efficiency of solutions can be done by comparing the time it takes them to perform the same task. Essential Knowledge CSN-2.A.5: A sequential solution takes as long as the sum of all of its steps. Essential Knowledge CSN-2.A.6: A parallel computing solution takes as long as its sequential tasks plus the longest of its parallel tasks. Essential Knowledge CSN-2.A.7: The speedup of a parallel solution is measured in the time it took to complete the task sequentially divided by the time it took to complete the task when done in parallel.
Learning Objective CSN-2.B: Describe benefits and challenges of parallel and distributed computing.
Skill 1.D CSN-2.B.1 CSN-2.B.2 CSN-2.B.3 CSN-2.B.4 CSN-2.B.5 Essential Knowledge CSN-2.B.1: Parallel computing consists of a parallel portion and a sequential portion. Essential Knowledge CSN-2.B.2: Solutions that use parallel computing can scale more effectively than solutions that use sequential computing. Essential Knowledge CSN-2.B.3: Distributed computing allows problems to be solved that could not be solved on a single computer because of either the processing time or storage needs involved. Essential Knowledge CSN-2.B.4: Distributed computing allows much larger problems to be solved quicker than they could be solved using a single computer. Essential Knowledge CSN-2.B.5: When increasing the use of parallel computing in a solution, the efficiency of the solution is still limited by the sequential portion. This means that at some point, adding parallel portions will no longer meaningfully increase efficiency.

Professional Development

The Student Lesson: Complete the activities for Mobile CSP Unit 5: Lesson 5.9 Parallel Computing.

Materials

• Text version of the student lesson - This document should be broken into several parts and interspersed with activities, as described below.
  
• Video Clip: Distributed Computing  with Folding @ Home (4:57)
• A deck of playing cards for every group of 4 students
• Alternatively, you can use PlayingCards.io (scroll down and click 'Other')
• Computer lab with projection system

5.10.1. Learning Activities

Estimated Length: 45 minutes

• Hook/Motivation (5 minutes): Take this time to review the searching and sorting algorithms (from earlier in this unit) with students as well as review how algorithms are analyzed by their efficiency. 
• Experiences and Explorations (35 minutes):
  • Part 1 - Parallel Computing: Introduce the concepts of sequential, parallel, and distributed computing. Explain how the speedup of a parallel solution is determined.
  • POGIL Activity #1 - Searching: Divide the class into groups of four. Give each group a deck of playing cards and have them complete the tasks.
  • Part 2 - Benefits and Challenges of Parallel Computing: Share and discuss some of the benefits and challenges of using parallel computing.
  • POGIL Activity #2 - Sorting: Divide the class into groups of four. Give each group a deck of playing cards and have them complete the tasks. By doing this activity students should gain an understanding that the speed is controlled by dividing and merging the deck.
  • Part 3 - Distributed Computing: Use the diagram to explain the differences between parallel and distributed computing. Then watch the distributed computing video (if you are running low on time, you may choose to show parts of the video).
• Rethink, Reflect and/or Revise (5 minutes): Have students complete the interactive exercises and portfolio reflections.

AP Classroom

The College Board's AP Classroom provides a question bank and Topic Questions. You may create a formative assessment quiz in AP Classroom, assign the quiz (a set of questions), and then review the results in class to identify and address any student misunderstandings.The following are suggested topic questions that you could assign once students have completed this lesson.

Suggested Topic Questions:

• Topic 4.3 - Parallel and Distributed Computing

Assessment Opportunities and Solutions

Solutions Note: Solutions are only available to verified educators who have joined the Teaching Mobile CSP Google group/forum in Unit 1.

• Quizly Solutions
• Portfolio Reflection Questions Solutions

Assessment Opportunities

You can examine students’ work on the interactive exercise and their reflection portfolio entries to assess their progress on the following learning objectives. If students are able to do what is listed there, they are ready to move on to the next lesson.

• Interactive Exercises:
• Portfolio Reflections:
  LO X.X.X - Students should be able to ...

Differentiation: More Practice

If students are struggling with lesson concepts, have them review the following resources:

Differentiation: Enrichment

Background Knowledge

Teaching Tips

5.10.2. Professional Development Reflection

Discuss the following questions with other teachers in your professional development program.

I am confident I can teach this lesson to my students.
• 1. Strongly Agree
• 2. Agree
• 3. Neutral
• 4. Disagree
• 5. Strongly Disagree