6.846 Parallel Computing (H)

Spring 2008

Classroom Change: 6.846 now held in 32-155

Professor Anant Agarwal
agarwal@mit.edu
Course webpage: http://cag.csail.mit.edu/classes/6.846

Meeting Times: Tuesday & Thursday, 2:30-4pm in room 32-155
Prerequisite: 6.004 or permission of instructor
Units: 3-0-9, H-level grad credit

Underground Guide Evalution

We encourage you to fill out a course evaluation at this website (https://sixweb.mit.edu/student/evaluate/6.846-s2008). This link will become active on May 7th.

Final Project Presentations

5/13/2008 - Final presentations are on Thursday. 

· Class will meet from 1-5 in the 7th floor lounge of 32 G (Gates tower of the stata center).  We know that not everyone can make it for the entire time, but please attend as much as possible.  Also, if possible please email me an electronic copy of your slides by noon on Thursday.  We will try to minimize laptop changes during the presentations and hopefully speed everyone along.

5/09/2008 – There is no report due for the final project. You only need to turn in a copy of the slides you present in class. The sign up sheet for the demo is available in class and in office hours.

As of 4/29/2008 - The presentation on the final project will be split into two parts.  The first part will be done in class and the second part will be a demo presented to me.  Here are some more details on each of the two parts:

• In class presentation:
• Every team member must present some part of the in class portion.
• Teams of one person can take 6 minutes.
• Teams of >=2 should allocate up to 4 minutes per team member
• We recommend three slides per team member
• Each team member must include at least one slide covering their individual contribution to the work
• Please bring 2 hard copies of the slides to class
• Demo to the TA
• This is a chance to show off what you have done in more depth and go into a more rigorous explanation
• These presentations will be done in 15 minute blocks
• They should demo the software for the project and cover any additional information not covered in class
• These will be done by appointment in the last week of class
• I will create a sign up sheet as we get closer to the end of class

Design Project News/Notes

Last updated 5/13/2008…

• Here are the values for C we will be using in evaluating the design contest:
• For the rawtile, C = 10,000.
• For the 10010 node list, C = 1024
• For the 2505 node list, C = 64
• For the 103 node list, C = 100
• We will not be pinning any nodes for the evaluation, so there are no restrictions on where you place the nodes.
• As Anant described in class, you should produce a chart showing the sum of the total wire length as a function of time in cycles.  You may start timing the program at the point when your program has finished parsing the input file.  You should collect data points at a wide range of cycles to clearly illustrate the curve.  When you are collecting data please highlight the points at 42, 84, and 210 Billion cycles past the start time.  (That is 1, 2, and 5 minutes past the time when your program has completed reading the file.) 
• Update on design contest requirements:
• In the DesignContest-v2.ppt file, we have the constraint:

The difference between the maximum number of nodes per cell and the minimum number of nodes per cell should not exceed 0.01 x N/C.

• Some folks have noted that given the typical values of N=100000 and C=1000, .01 x N/C = 1, which is a stricter constraint than we intended.
• In terms of the load balancing between cells, your program should be able to handle any reasonable constraint, whether it is 0.01 N/C or 0.05 N/C. The main thing is that the program should be parameterized to handle values that are similar, but not exactly equal to the typical values presented in the spec.
• The design project slides have been updated to reflect that here.
• Some example inputs are available from this website.  These examples only contain one file b the one specifying the graph.  It is assumed that people can experiment with their own text files specifying immovable nodes.
• Here is an example with 103 nodes.
• Here is an example with 2505 nodes.
• Here is an example with 10010 nodes.
• Note that these three examples were generated electronically.  Let the TA know if there are any issues.

Course News and Announcements

4/29/2008 - Project status reports are due May 1^st in class.

4/4/2008 - If you received feedback on your project proposals, please respond to that feedback by April 10^th.

4/4/2008 - Updated details on the design project are available here. The update includes an example of the input file formats we will use for the final input.        

4/4/2008 - TILE64 hardware is available to the class.

3/16/2008 - Class project news:

Proposals for the class project are due 3/20/2008

Proposals should be 1-2 pages and should include the following information:           

      Who is working on the project?

      What problem is the project addressing?

                        What approach is the team taking to tackle this problem? (Just a high-level description is all that is needed here.)

      How is the team dividing the work of the project among team members?

Students looking for partners for the project are encouraged to meet after class on 3/18/2008

Details on the design contest option for the class project can be found here.

3/4/2008 - After a brief stint in 35-225, class has moved again to 32-155

2/28/2008 - 6.846 now available in a new, larger room b specifically 35-225

2/26/2008 - You can download the video demo on acoustic beamforming from todaybs lecture here. (Right click on the link and choose bSave Link As b)

2/14/2008 - first assignment is out, students will be receiving passwords on class machine (blokus.csail.mit.edu) today

2/7/2008 - TA office hours are posted: Wednesday @ 1:00 PM and Friday @ 11:00 AM (Except Friday February  8^th)

Course Project

An overview of the design contest option for the class project can be found here.

Course Description

Course description is here.

Administrative Staff

• Simone Nakhoul, 32-G784A, x3-2629, snakhoul@mit.edu

Teaching Assistant

• Henry (Hank) Hoffmann, 32-G740, x3-0674, hank@cag.csail.mit.edu
• Office Hours: Wednesday @ 1-2 PM and Friday @ 11AM-12PM

Handouts

If there is no link to a handout, it is not available electronically.  You can get hard copy from Hank or Simone in their offices.

• Handout 1 - Course Intro
• Handout 2 - Course Schedule
• Handout 3 - Lecture 1 Notes
• Handout 4 - Iterative Methods
• Handout 5 - The Weather Problem
• Handout 6 -  Solutions to Tridiagonal Systems
• Handout 7 - Lecture 2 Notes
• Handout 8 - Lecture 3 Notes
• Handout 9 - HW1
• Handout 10 - Laboratory Handout 1 b Intro to multicore programming
• Handout 11 - Lecture 4 notes
• Handout 12 - Packet processing paper from Intel
• Handout 13 - Lecture 5a notes b stream problems, networking
• Handout 14 - Lecture 5b notes b stream problems, radar processing
• Handout 15 - Experience with two parallel programs solving the TSP
• Handout 16 - Lecture 6 notes, graph problems
• Handout 17 - Modeling the performance of hypercubes
• Handout 18 - HW2
• Handout 19 - Lecture 7 notes b particle problems
• Handout 20 - h.264 paper
• Handout 21 - Lecture 8 notes b video processing
• Handout 22 - Cell processor paper
• Handout 23 - Intel TRP paper
• Handout 24 - Tilera Interconnect paper
• Handout 25 - Lecture 9 notes b Computational Models
• Handout 26 - RP3 paper
• Handout 27 - Data Parallel Paper
• Handout 28 - Cosmic Cube Paper
• Handout 29 – HW3 grain size
• Handout 30 - Memory requirements for a balanced computer architecture
• Handout 31 - Simplefit Paper
• Handout 32 - Lecture 10&11 b grain size lecture
• Handout 33 - Lecture 12&13 b machines and languages
• Handout 34 - k-ary n-cube paper
• Handout 35 - Limits of interconnection networks
• Handout 36 - HW1 solutions
• Handout 37 – HW2 solutions
• Handout 38 - HW4
• Handout 39 - Lecture 14&15 - Interconnection networks
• Handout 40 - SUN niagara paper
• Handout 41 - L16 performance evaluation of networks
• Handout 42 - Scalar operand networks
• Handout 43 - Scalability paper
• Handout 44 - OpenMP lecture slides
• Handout 45a - MPI lecture slides
• Handout 45b - Mapreduce lecture slides
• Handout 46 - L17a technology primer
• Handout 47 - L18 networks physical constraints
• Handout 48 - L17b scalability
• Handout 49 - Directory paper
• Handout 50 - Per coherence survey paper
• Handout 51 – HW3 solutions
• Handout 52 - L19-20 memory systems, perf-eval
• Handout 53 - Algorithms for Scalable Synchronization on Shared-Memory Multiprocessors
• Handout 54 - Reactive synchronization.
• Handout 55 - Transactional memory paper

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Maintained by: Jason Miller (jasonm@mit.edu)