3rd Largest Element: SIMD Edition
6 hours ago
- #Performance Optimization
- #AVX2
- #SIMD
- The article explores SIMD-accelerated implementations for finding the third largest element in an array, focusing on performance improvements.
- SIMD implementations are discussed for small k (k<=8), leveraging AVX2 registers to optimize insertion operations.
- Different AVX2 variants are presented: naive, least (inserts first qualifying element), and peel (processes all qualifying elements).
- Performance analysis shows AVX2 implementations are significantly faster (5-7x) for random and reverse-sorted inputs but slower for sorted inputs.
- The article highlights the trade-offs between SIMD optimizations and scalar implementations, with nth_element() performing better on sorted data.
- Source code is available on GitHub for further exploration and experimentation with AVX512 or multi-register approaches.