Performance - How to write efficient systems software

In this chapter we will look at a topic that is near-and-dear to many systems programmers: Performance! Performance is this mythical attribute that a software can have which makes it go fast! Of course there is a bit more to performance than just 'running fast'. In this chapter we will take a look at what it means for a piece of software to have good performance, and how we can achieve this goal.

The topics covered in this chapter are:

• What is performance, and how do we know that we have it?
• Understanding performance through benchmarking and profiling
• Tips for writing efficient code for systems software
• Vectorization