Optimization TechniquesΒΆ
Prerequisites: Algorithm analysis, Basic profiling
Learning ObjectivesΒΆ
- Optimize code based on measured bottlenecks.
- Apply safe and maintainable optimizations.
- Validate gains with benchmarks.
Optimization OrderΒΆ
- Measure current behavior.
- Improve algorithmic complexity first.
- Reduce repeated work with caching/memoization.
- Optimize data structure choice.
- Re-measure and verify no regression.
Useful TechniquesΒΆ
Swapping OperationsΒΆ
Swapping values is a fundamental operation. While using a temporary variable is common and clear, some languages offer atomic or optimized ways to swap. Minimizing unnecessary swaps in sorting algorithms is a key performance win.
Bitwise OperationsΒΆ
Bitwise operations (AND, OR, XOR, shifts) are extremely fast as they operate directly on the binary representation of numbers. They can be used for: - Efficiently checking for odd/even numbers. - Swapping numbers without a temporary variable (XOR swap). - Fast multiplication or division by powers of two.
Memory OptimizationΒΆ
Reducing memory footprint can improve performance by increasing cache hits and reducing garbage collection frequency. - Reuse objects instead of creating new ones. - Choose data structures that use less overhead. - Use primitive types instead of wrapper objects where possible.
SummaryΒΆ
Optimize where it matters most, and always verify with data.