M10 Performance

This skill helps you make your code run faster and use fewer resources. You will learn to find the real bottleneck before making changes. The most important step is to measure first with tools like profiling and benchmarks. Guessing is never a good idea. Once you know the problem, you can choose the right fix.

Techniques include reducing memory allocations, improving cache use, and adding parallelism. For example, pre-allocating space with with_capacity avoids many small allocations. Using contiguous data like Vec instead of HashMap helps the CPU cache work better. You can also avoid copying data by using references. The goal is to trade small complexity for big speed gains.

Common mistakes are optimizing without profiling or benchmarking in debug mode. The skill lists clear priorities. Algorithm changes give the biggest improvement, then data structures, then allocations, then cache tuning. Use the quick reference to pick the right tool like cargo bench or perf. This skill is for anyone who wants to make their programs faster and more efficient.