Performance Programming

In this lesson, you will learn to write efficient programs. Or at least get a first impulse; only by applying these techniqes in your own code you will truly understand them. It is also not just a set of techniques, but a mind set that you will acquire by using it.

We will deal with efficiency on several different levels:

  • Algorithm: What are the basic steps your program performs and how are the data structures organized?

  • Compiler: What can the compiler do for you, and how can you help it?

  • Hardware: How does a modern processor work, and how can you adapt your program to it?

  • Performance analysis: Does your program run in the way you intended?

We will address these questions in a language and architecture agnostic way as far as possible, with code examples in C (and Fortran, when I have brushed up a bit). Our main architectural example will be the x86 and its implementations.

Prerequisites

Before attending this workshop, please make sure that you have access to a computer with a C or Fortran compiler installed. Linux would be the preferred operating system, but at least the algorithm part should be reasonably OS independent. Performance measurement works best when not run on a virtual machine; a dedicated machine like an ordinary laptop works just fine.

1h 30min

Algorithms

1h 45min

Compilers

4h

Architecture

4h

Tuning

Reference

Who is the course for?

This lesson material is targeted towards students, researchers, engineers, and developers who write programs that they would like to run faster. The focus of the course is on mid level languages like C, C++, Fortran and so on, but most of the issues discussed are relevant for assebly code, and at least the algorithm part can be useful for code written in high level languages such as Julia and Haskell.

The course assumes familiarity with C or Fortran syntax which is used for the code examples, but no knowledge of computer architecture or complexity theory is needed.

About the course

This lesson material is developed by the EuroCC National Competence Center Sweden (ENCCS) and taught in ENCCS workshops. Each lesson episode has clearly defined learning objectives and includes multiple exercises along with solutions, and is therefore also useful for self-learning. The lesson material is licensed under CC-BY-4.0 and can be reused in any form (with appropriate credit) in other courses and workshops. Instructors who wish to teach this lesson can refer to the Instructor’s guide for practical advice.

See also

Credits

The lesson file structure and browsing layout is inspired by and derived from work by CodeRefinery licensed under the MIT license. We have copied and adapted most of their license text.

Instructional Material

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Software

Except where otherwise noted, the example programs and other software provided with this repository are made available under the OSI-approved MIT license.