[[Category:Fall 2014 Winter 2015 SPO600]]{{Chris Tyler Draft}}{{Admon/important|It's Alive!obsolete|This [[Current SPO600Weekly Schedule]] weekly schedule will be updated as the course proceeds - dates and content are subject to change. The cells in the summary table will be linked to relevant resources and labs as the course progresses.}}

== Schedule Summary Table ==

|1||Jan 12||[[#Tuesday (Jan 13)|Introduction to Software Porting, Portability, Benchmarking, and Optimization / How is code accepted into an open source project? (Lab 1)]]||[[#Thursday (Jan 15)|Computer Architecture OverviewBenchmarking and Profiling]]||[[#Week 1 Deliverables|Set up accounts, and blog a comparision of code reviews in two communities (Lab 1).]]

|2||Jan 19||[[#Tuesday (Jan 20)|Compiled C Lab (Lab 2)Working with the code / Building]]||[[#Thursday (Jan 22)|Prepare Build and benchmark a presentation on a selected aspect portion of assembly languagethe LAMP stack (Lab 2)]]||[[#Week 2 Deliverables|Blog a commentary on the Compiled C Lab about your baseline data (Lab 2), and be prepared to give your presentation.]]

|3||Jan 26||[[#Tuesday (Jan 27)|Assembly language presentationsProfiling: Finding the pain points (Lab 3)]]||[[#Thursday (Jan 29)|Assembly language presentationsComputer architecture overview]]||[[#Week 3 Deliverables|Blog about your assembly language presentation.the profiling results and pain points discovered (Lab 3)]]

|4||Feb 2||[[#Tuesday (Feb 3)|Assembly lab Compiled C Lab (Lab 34)]]||[[#Thursday (Feb 5)|Inline assembler / Potential project triage - Scan the potential project list to find out about the packagesCompiler optimizations]]||[[#Week 4 Deliverables|Blog post about a commentary on the assembly lab Compiled C Lab (Lab 34) and what you found in the potential projects.]]

|7||Feb 23 ||[[#Tuesday (Feb 24)|Working with the code / Find the platform-specific code in 3 packages Assembly lab (Lab 45).]]||[[#Thursday (Feb 26)|Group hack session - Picking your packages.Inline assembly lab and Course Projects]]||[[#Week 6 7 Deliverables|Blog about the platform-specific code in 3 packages Assembly Lab (Lab 45) and the packages you selectedstart project investigation.]]

|Study Week||Mar 2||colspan="3" align="center"|Study Week - No classes!Please work on your initial project investigation.

|8||Mar 9||[[#Tuesday (Mar 10)|Project Presentations - Stage 1discussion, and Reading Reference Documentation.]]||[[#Thursday (Mar 12)|Benchmarking and profilingProject presentations - Stage 1]]||[[#Week 7 8 Deliverables|Blog about your project plans progress - this will be used to assign your 1st Project Marksmarks.]]

|9||Mar 16||[[#Tuesday (Mar 17)|Group hack - Baseline builds and benchmarkingUpstreaming]]||[[#Thursday (Mar 19)|Compiler OptimizationsSpinlocks and Tail Call Optimization]]||[[#Week 9 Deliverables|Blog about your baseline dataproject work.]]

|10||Mar 23||[[#Tuesday (Mar 24)|Optimization LabPortable alternatives to Assembler]]||[[#Thursday (Mar 26)|Group Hack Project Presentations - Profiling: Finding the Pain PointsStage 2]]||[[#Week 8 10 Deliverables|Blog about the pain points in your softwareproject progress - this will be used to assign your 2nd Project Marks.]]

|11||Mar 30||[[#Tuesday (Mar 31)|Project Presentations - Stage 2Hack Session]](Professor will not be present)||[[#Thursday (Apr 2)|Group Hack - OptimizationSIMD]]||[[#Week 9 11 Deliverables|Blog about SIMD/vectorization and your project progress - this will be used to assign your 2nd Project Marks.]]

|12||Apr 6||[[#Tuesday (Apr 7)|UpstreamingDiscussion & Hack Session]]||[[#Thursday (Apr 9)|Discussion & Hack SessionVectorization]]||[[#Week 10 12 Deliverables|Blog about your progresswork.]]

|13||Apr 13||[[#Tuesday (Apr 14)|Discussion and hack sessionProject Presentations - Stage 3]]||[[#Thursday (Apr 16)|Wrap-up Session]]||[[#Week 11 13 Deliverables|Upstream Blog about your work and blog about itproject progress - this will be used to assign your 3rd project marks.]]

|Project work||align="right"|60%||March 13 16 (15%), April 3 March 31 (20%), April 22 (25%)

==== Introduction to the Problem Problems ====

===== Porting and Portability =====* Most software is written in a '''high-level language''' which can be compiled into [[Machine Language|machine code]] for a specific computer architecture. In many cases, this code can be compiled for multiple architectures. However, there is a lot of existing code that contains some architecture-specific code fragments written in [[Assembly Language]] (or, in some cases, machine-specific high-level code).

* There are over 1400 At this point, most key open source software (the software packages/modules typically present in GNU a Linux systems which contain distribution such as Ubuntu or Fedora, for example) now runs on AArch64. However, it may not run as well as on older architectures (such as x86_64). ===== Benchmarking and Profiling =====Benchmarking involves testing software performance under controlled conditions so that the performance can be compared to other software, the same software operating on other types of computers, or so that the impact of a change to the software can be gauged. Profiling is the process of analyzing software performance on finer scale, determining resource usage per program part (typically per function/method). This can identify software bottlenecks and potential targets for optimization. ===== Optimization =====Optimization is the process of evaluating different ways that software can be written or built and selecting the option that has the best performance tradeoffs. Optimization may involve substituting software algorithms, altering the sequence of operations, using architecture-specific [[Assembly Language|assembly language code]] , or altering the build process. It is important to ensure that the optimized software produces correct results and does not cause an unacceptable performance regression for other use-cases, system configurations, operating systems, or have architectures. The definition of "performance" varies according to the target system and the operating goals. For example, in some contexts, low memory or storage usage is important; in other cases, fast operation; and in other portability issuescases, low CPU utilization or long battery life may be the most important factor. It is often possible to trade off performance in one area for another; using a lookup table, for example, can reduce CPU utilization and improve battery life in some algorithms, in return for increased memory consumption.  Most advanced compilers perform some level of optimization, and the options selected for compilation can have a significant effect on the trade-offs made by the compiler, affecting memory usage, execution speed, executable size, power consumption, and debuggability. ===== Build Process =====Building software is a complex task that many developers gloss over. The simple act of these compiling a program invokes a process with five or more stages, including pre-proccessing, compiling, optimizing, assembling, and linking. However, a complex software system will have hundreds or even thousands of source files, as well as dozens or hundreds of build configuration options, auto configuration scripts (cmake, autotools), build scripts (such as Makefiles) to coordinate the process, test suites, and more. The build process varies significantly between software packages cannot . Most software distribution projects (including Linux distributions such as Ubuntu and Fedora) use a packaging system that further wraps the build process in a standardized script format, so that different software packages can be built on Aarch64 systems without modificationusing a consistent process. In order to get consistent and comparable benchmark results, you need to ensure that the software is being built in a consistent way. Altering the build process is one way of optimizing software. Note that the build time for a complex package can range up to hours or even days!

# Select two software packages from a list compiled by Steve Macintyre Test the performance of all or part of Linarothe LAMP stack. Each # Determine how the performance of one specific part of the packages stack could be improved, either specifically on AArch64 systems (without detriment to other systems) or on this list contains assembly language code which is platform-specificall systems.# Prepare a fix/patch for the software so to implement that it will run on 64-bit ARM systems (aarch64). This may be done at either of two levels:## Port - Add additional assembly language code for aarch64 (basic solution).## Make Portable - Remove architecture-specific code, replacing it with compiler intrinsics or high-level code so that the software will successfully build on multiple platformsperformance improvement.# Benchmark - Prove that your changes do not cause a any unacceptable performance regression on existing platforms, and that regressions (ideallyNote: there might be performance regressions which are considered acceptable!) it improves performance.# Upstream your Code - Submitting Submit 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.

* Background for the [[SPO600 Code Review Lab|Code Review Lab (Lab 1)]].

* [[Computer Architecture]] overview (see also the [[:Category:Computer Architecture|Computer Architecture Category]])Benchmarking* Profiling

# Add yourself to the [[Fall 2014 Winter 2015 SPO600 Participants]] page (leave the projects columns blank).

# Optional but recommended: [[SPO600 Host Setup|Set up a personal Fedora 20 system]].

{{Admon/tip|Bring Your Laptop|Classes are held in a [[Active Learning Classroom]]. If you have a laptop or other device with a VGA or HDMI output (such as a smartphone!) please bring it. You'll need either a local linux environment or an [[SSH ]] client -- which is built-in to Linux, Mac, and Chromebook systems, and readily available for Windows, Android, and iOS devices.}} Status Check* Introductions around the Room** Name** Program** Perform Interest in the course** Results of <code>gzip</code> benchmarking and most interesting thing you observed* Check the [[SPO600 Compiled C LabServers|Compiled C Lab server accounts]] that were set up with your [[SSH]] keys* Sheets from Last Week** Open Source Student Agreement** Survey (Lab Optional) Working with the Code* Getting Code** In a tarball** From git*** Git basics** Working with other version control systems* Building the Code** Make** Configuration tools (autotools, cmake)** The compiler toolchain*** Preprocessor*** Compiler*** Assembler*** Linker** Debug vs. Non-debug/Stripped binaries Looking at How Distributions Package the Code* Using fedpkg ==== Resources ====* [https://sourceware.org/binutils/docs-2).16/gprof/ GProf Manual]* [http://www.thegeekstuff.com/2012/08/gprof-tutorial/ Profiling with GProf] in groups.

 * [[Winter 2015 SPO600 Assembly Language PresentationBaseline Builds and Benchmarking Lab|Select Baseline Builds and prepare to teach the class about a specific small topic related to assembly language / machine language programmingBenchmarking Lab (Lab 2)]].

* Blog your conclusion baseline data from the [[SPO600 Baseline Builds and Benchmarking Lab|Baseline Builds and Benchmarking lab (Lab 2)]].  == Week 3 == === Tuesday (Jan 27) === Profiling* Profiling with <code>gprof</code>** Build with profiling enabled (use the option <code>-pg</code> with both gcc and ld)** Run the profile-enabled executable** Analyze the data in the <code>gmon.out</code> file*** <code>gprof ''nameOfBinary''</code> # Displays text profile including call graph*** <code>gprof ''nameOfBinary'' | gprof2dot | dot | display -</code> # Displays visualization of call graph* Other profiling tools** OProf, SystemTap, and others* [[SPO600 Profiling Lab]] (Lab 3) === Thursday (Jan 29) === * [[Computer Architecture]] overview (see also the [[:Category:Computer Architecture|Computer Architecture Category]]) === Week 3 Deliverables === * Complete and blog your conclusions to the [[SPO600_Compiled_C_LabSPO600 Profiling Lab|Profiling Lab (Lab 3)]].  == Week 4 == === Tuesday (Feb 3) ===* [[SPO600 Compiled C Lab|Compiled C Lab (Lab 24)]] === Thursday (Feb 5) ===* [[Compiler Optimizations]] === Week 4 Deliverables ===* Blog your [[SPO600 Compiled C Lab|Compiled C Lab (Lab 4)]]results. Be sure to include a reflective section on what you learned.* Select your topic for the [[Winter 2015 SPO600 Platform Specific Code Presentation|Platform-Specific Code Presentation]]. == Week 5 ==* Prepare your [[Winter 2015 SPO600 Platform Specific Code Presentation|Platform-Specific Code Presentation]]. === Week 5 Deliverables ===* Be prepared ready to give [[Winter 2015 SPO600 Platform Specific Code Presentation|present]]. == Week 6 ===== Tuesday (Feb 17) ===* Introduction to the [http://www.96boards.org/products/hikey/ HiKey] board and the [http://www.96boards.org/ 96Boards] project.* [[Winter 2015 SPO600 Platform Specific Code Presentation|Presentations on platform-specific code]] === Thursday (Feb 19) ===* [[Winter 2015 SPO600 Platform Specific Code Presentation|Presentations on platform-specific code]] === Week 6 Deliverables ===* Blog about your presentation. == Week 7 ===== Tuesday (Feb 24) ===* [[SPO600 Assembler Lab|Assembly language lab (Lab 5)]] === Thursday (Feb 26) ===* Remaining [[Winter 2015 SPO600 Platform Specific Code Presentation|Presentations on platform-specific code]]* [[Inline Assembly Language Presentation]]* [[Winter 2015 SPO600 Project|Course Projects]] === Week 7 Deliverables ===* Blog your conclusion to the [[SPO600 Assembler Lab|assembly language lab (Lab 5)]] - See the ''Deliverables'' section in the lab instructions for details on what to include in your blog post. == Week 8 == === Tuesday (Mar 10) ===* Project discussion** Discussion of project ideas and fine-tuning of project plans** Next steps** Addressing Problem Areas* Accessing and Reading Reference Documentation** AArch64 ISA === Thursday (Mar 12) ===* Project presentations** Provide a very short (2 minute) overview of your project. Include:*** Which piece of software you are working on*** What area of that software needs optimization/performance tuning*** How you are going to perform the optimization/tuning (algorithm replacement, platform-specific code, removing platform-specific code, build options, and so forth)*** Plans for the next step*** Engagement with the upstream community* Use this project presentation to tell the class what you're working on and incorporate feedback into your blog post === Week 8 Deliverables ===* Blog about your project and plans, incorporating feedback from your presentation* Add your project to the [[Winter 2015 SPO600 Participants|Participants and Project Table]] . == Week 9 == === Tuesday (Mar 17) ===* Upstreaming** Git Discussion** Creating a Patch** Various open source community workflows === Thursday (Mar 19) ===* Spinlocks** The need for Atomics in Spinlocks** Using Intrinsics for Atomic Operations* Tail Call Optimization (TCO)** gcc will perform TCO at -O2 and higher** Important to ensure that gcc recognizes code patterns that permit TCO to be applied === Week 9 Deliverables ===* Blog at least once (and ideally more than once) about your Project** Frequent shorter posts are better than rare long ones** Aim to make steady progress on your project, a bit each day** Blog about your evolving project plan and the steps you're making along the way** Keep the work short, and focus on narrowing the scope of work as early as possible** Keep talking to the community == Week 10 == === Tuesday (Mar 24) ===* Discussion of GCC Intrinsics** Where to find documentation: [https://gcc.gnu.org/onlinedocs/ GCC Manual]** __atomic vs __sync intrinsic families* Examination of Build Files** Differential analysis of successful and unsuccessfull build === Thursday (Mar 26) ===* Project Presentations - Stage 2** At this point, you should have a proposed patch that you're working to get upstream === Week 10 Deliverables ===* Blog posts about your project** Include information about your patch(es)** Include links to discussion about the patch(es) with the community (e.g., link to bug/issue tracker entries or email archives)** If you don't have patches and/or have not pushed them upstream yet, describe the state of your project and your plan to get changes upstream.* Blogs will be marked Monday for Stage 2 project work (20%) == Week 11 == === Tuesday (Mar 31) ===Your professor will be away. You are welcome to use the classroom for a project hacking time and collaboration with your colleagues. === Thursday (Apr 2) ===* Single Instruction / Multiple Data (SIMD)** Brief look at x86_64 & AArch64 implementations of next SIMD === Week 11 Deliverables ===* Blog about your ongoing project work. Please post at least 1-2 entries per week. == Week 12 == === Tuesday (Apr 7) ===* Discussion & Hacking Session === Thursday (Apr 9) ===* Vectorization** Using Intrinsics** Using Auto-Vectorization === Week 12 Deliverables ===* Blog about your ongoing project work. Please post at least 1-2 entries per week.* You should have patches (code, makefiles, documentation, or tests) in the upstream review process at or before this point.* Blog about vectorization - specifically:** What -O level and/or options are needed to turn on the auto-vectorizer in GCC** At least three limitations -- conditions under which the vectorization will not be performed** The significance of alignment and non-overlapping pointers for vectorization == Week 13 == === Tuesday (Apr 14) ===* Informal Project Presentations - Phase 3 === Thursday (Apr 16) ===* Wrap-up Session === Week 13 Deliverables ===* Blog about your ongoing project work. Your patches should be through the upstream review process.* Final date for posting about your project: April 22.