The Hardware Knowledge That Every Programmer Should Know
6 hours ago
- #hardware
- #performance
- #optimization
- Programmers need hardware knowledge to optimize high-performance code.
- Cache behavior affects performance: row-major iteration is faster than column-major due to cache line efficiency.
- Random array traversal is slower than column-major due to prefetcher inefficiency.
- Cache associativity impacts performance; strides that are powers of 2 cause spikes in runtime.
- False sharing occurs when threads modify variables on the same cache line, reducing efficiency.
- Memory alignment can prevent false sharing by ensuring variables are on separate cache lines.
- Branch prediction affects pipeline efficiency; sorted arrays perform better than shuffled ones.
- Data dependence between iterations reduces pipeline efficiency and prevents vectorization.
- Independent iterations allow for better compiler optimizations like vectorization.