Winter 2014 SPO600 Weekly Schedule

From CDOT Wiki
Revision as of 01:00, 5 September 2014 by Chris Tyler (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search
This page may be obsolete.
It contains historical information. For current information, please see the Current SPO600 Weekly Schedule.

Summary Table

This is a summary/index table. Please follow the links in each cell for additional detail -- especially for the Deliverables column.

Week Week of... Tuesday - Class Friday - ALC/Lab Deliverables
1 Jan 6 Introduction to Software Porting, Portability, Benchmarking, and Optimization How is Code Accepted? - Analyze code submissions in two separate open source projects Blog a commentary on code reviews in two communities (Lab 1)
2 Jan 13 Computer Architecture Overview Hello World - Compile a basic C program and analyze the resultant binary Set up a Fedora system and the ARMv8 Foundation Model / Blog on binary analysis (Lab 2)
3 Jan 20 Introduction to Assembly Language x86_64 and Aarch64 Assembley Language Blog about writing in assembly language (Lab 3)
4 Jan 27 Lab 3 results, inline assembler, and compiler optimizations Analyzing a codebase for assembler and non-portable code Blog post about codebase analysis
5 Feb 3 Memory Barriers and Atomics Potential Project Analysis Blog about your selected projects
6 Feb 10 Architecture-specific Code for Performance Group hack session - Porting Identify the assembler in your projects and contact your upstream communities.
7 Feb 17 Portability - Removing platform-specific code Group hack session - Portability Remove platform-specific code from your projects
Study Week Feb 24 Study Week
8 Mar 3 Project Work Project Work Get code into review
9 Mar 10 Status Update Foundation Models Install and Test With Foundation Model
10 Mar 17 Profiling Baseline Profiling Post baseline stats for your software
11 Mar 24 Optimizing Code Group hack - Profiling and optimizing Code review update
12 Mar 31 Using complier optimizations Project Work Code review update
13 Apr 7 Final Presentations (No class - Exams start) Code accepted upstream
Exam Week Apr 14 Exam Week - No exam in this course!


Category Percentage Evaluation Dates
Communication 20% Jan 31, Feb 28, March 31, April 13
Quizzes 10% May be held during any class. A minimum of 5 one-page quizzes will be given. Lowest 3 scores will not be counted.
Labs 10% See deliverables column above.
Project work 60% Feb 28, March 31, April 13

Week 1

Tuesday (Jan 7)

  • Introduction to the Problem
    • Most software is written in a high-level language which can be compiled into machine code for a specific architecture. However, there is a lot of existing code that contains some architecture-specific code fragments written in Assembly Language.
    • Reasons for writing code in Assembly Langauge include:
      • Performance
      • Atomic Operations
      • Direct access to hardware features, e.g., CPUID registers
    • Most of the historical reasons for including assembler are no longer valid. Modern compilers can out-perform most hand-optimized assembly code, atomic operations can be handled by libraries or compiler intrinsics, and most hardware access should be performed through the operating system or appropriate libraries.
    • A new architecture has appeared: Aarch64, which is part of ARMv8. This is the first new computer architecture to appear in several years.
    • There are over 1400 software packages/modules present in GNU Linux systems which contain architecture-specific assembly language code. Most of these packages cannot be built on Aarch64 systems without modification.
  • In this course, you will:
    1. Select two software packages from a list compiled by Steve Macintyre of Linaro. Each of the packages on this list contains assembly language code which is platform-specific.
    2. Prepare a fix/patch for the software so that it will run on 64-bit ARM systems (aarch64). This may be done at either of two levels:
      1. Port - Add additional assembly language code for aarch64 (basic solution).
      2. Make Portable - Remove architecture-specific code, replacing it with compiler intrinsics or high-level code so that the software will successfully build on multiple platforms.
    3. Benchmark - Prove that your changes do not cause a performance regression on existing platforms, and that (ideally) it improves performance.
    4. Upstream your Code - Submitting your code to the upstream (originating) software project so that it can be incorporated into future versions of the software. This will involve going through a code review to ensure that your code is compatible with and acceptable to the upstream community.
  • Optional: You can participate in the Linaro Code Porting/Optimization contest. For details, see the YouTube video of Jon "maddog" Hall and Steve Mcintyre at Linaro Connect USA 2013.
  • Course details:
    • Course resources are linked from the CDOT wiki, starting at (Quick find: This page will usually be Google's top result for a search on "SPO600").
    • Coursework is submitted by blogging.
    • Quizzes will be short (1 page) and will be held without announcement at any time. Your lowest three quiz scores will not be counted, so do not worry if you miss one or two.
    • Course marks:
      • 60% - Project Deliverables
      • 20% - Communication (Blog and Wiki writing)
      • 20% - Labs and Quizzes
    • Friday classes will be held in an "Active Learning Classroom". You are encouraged to bring your own laptop to these classes.
    • For more course information, refer to the SPO600 Weekly Schedule (this page), the Course Outline, and SPO600 Course Policies.

Friday (Jan 10)

Bring Your Laptop
Friday classes are held in a Active Learning Classroom. If you have a laptop or other device with an HDMI or VGA output (such as a smartphone!) please feel free to bring it.

Week 1 Deliverables

  1. Set up a blog and add it to Planet CDOT.
  2. Blog your conclusion to the SPO600 Code Review Lab.
  3. Add yourself to the Winter 2014 SPO600 Participants page (leave the projects columns blank).
  4. Sign and return the Open Source Professional Option Student Agreement.

Week 2

Tuesday (Jan 14)

Friday (Jan 17)

Week 2 Deliverables

Week 3

Tuesday (Jan 21)

Friday (Jan 24)

Week 3 Deliverables

Week 4

Tuesday (Jan 28)

Friday (Jan 31)

Week 4 Deliverables

  • Reminder: Week 1-3 blog posts are due for marking on Friday, January 31.
  • Blog about the Codebase Analysis Lab

Week 5

Tuesday (Feb 4)

Platform-specific code is often utilized for Memory Barriers and Atomics Operations.

Memory Barriers

Memory Barriers ensure that memory accesses are sequenced so that multiple threads, processes, cores, or IO devices see a predictable view of memory.


Atomics are operations which must be completed in a single step (or appear to be completed in a single step) without potential interruption.

Friday (Feb 7)

Hack Session: Potential Project Analysis

Select a project from the Winter 2014 SPO600 Software List and perform these steps:

  1. Edit that page to put your name in the "Claimed by" column.
  2. Investigate the package to determine:
    • If the current version has been built for ARM (e.g., exists in the Fedora aarch64 port - fastest way to test is to use 'yum' inside the arm64 emulation environment on Ireland)
    • What the platform-specific code in the software does
    • Whether portable work-arounds exist
    • The need for an aarch64 port or for platform-specific code elimination
    • Opportunities for optimization
    • The amount of work involved in porting and optimizing, and your skills for performing that work
  3. Based on the result of your investigation, decide on your interest in the project.
    • If you wish to choose this project for yourself, place it on your row in the Participants page.
    • If you do not wish to choose this project, remove your name from the "Claimed by" column in the Software List page.
  4. Repeat until you have two packages.
It is strongly recommended that you choose two projects with a total scope sum of 0-1. If you wist to try a higher or lower sum, or more or less than two projects, please talk to your professor.
RPM Packages
For sofware that is present in the rpmfusion repositories but not in Fedora, you can use yumdownloader --source packagename to grab the source RPM and then examine it using the RPM tools. See RPM Packaging Process for information.

Week 5 Deliverables

  • Blog about your two selected projects, including your detailed initial analysis of them.
    • You may want to break this into a couple of posts - e.g., post about your first package while you're working on your second.
    • Feel free to also blog about why you did not choose particular packages, too.

Week 6

Tuesday (Feb 11)

  • Architecture-specific code for Performance
    • Sometimes assembler is used in a C/C++ program for performance. However, modern versions of C/C++ (such as C++11) and recent compilers provide portable ways of accessing high-performance processor capabilities, such as Single Instruction/Multiple Data (SIMD) instructions (called "marketing names" such as SSE, Neon, MMX, 3DNow, or AltaVec on various processors).
    • Linaro enginener Matthew Gretton-Dann gave a good presentation on Porting and Optimizing Code for aarch64. The vectorization portion, beginning at 28:10, provides a good introduction to SIMD and autovectorization using GCC on aarch64 (Note that the earlier portion of the presentation includes good information about Atomics).
    • Note that in the presentation above, Matthew takes the code beyond portability without straying into assembler (e.g., using compiler-specific, architecture-specific intrinsics). It is possible to achieve almost all of the performance gains without becoming arch-specific, and most of those can be attained without becoming compiler-specific as well.
  • For full details on the SIMD instructions in aarch64, refer to the ARMv8 Instruction Set Overview, particularly section 5.7.

Week 6 Deliverables

  • Complete your analysis of your two selected software projects (if you haven't already) - see Week 5. Blog in detail about your findings.
  • Identify the upstream communities that develop and maintain the software you have selected to work on. Figure out how they are structured, how they communicate, how code is maintained, and how patches are accepted. Introduce yourself to each of the two communities (one for each of the two software projects you have selected). Blog about your findings.

Week 7

  • Project Work

Week 8

Week 9

Tuesday (March 11)

  • Status updates
  • Update from Linaro Connect
  • Discussion of useful tools
    • screen
    • time

Friday (March 14)


Week 9 Deliverables

  • Set up the Foundation Model
  • Upstream your proposed code changes
  • Blog about your work

Week 10

Tuesday (March 18)

  • Profiling with gprof
    • Build with profiling enabled (-pg)
    • Run the profile-enabled executable
    • Analyze the data in the gmon.out file
      • gprof nameOfBinary # Displays text profile including call graph
      • gprof nameOfBinary | gprof2dot | dot | display - # Displays visualization of call graph


Friday (March 21)

  • Gather baseline statistics for your software

Week 10 Deliverables

  • Blog your baseline benchmark results