The Treacherous Optimization (2006)
The author attempts to optimize Hex Fiend's string searching to surpass grep's performance but initially fails. They adopt grep's optimization technique, achieving slight improvements while questioning the trade-offs involved.
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The article discusses the author's attempt to optimize the string searching capabilities of Hex Fiend, a hex editor, to outperform the well-known tool grep. The author sets an ambitious goal to exceed grep's performance by 30% but initially finds that their implementation is significantly slower. They explore the Boyer-Moore algorithm for string searching, which allows for skipping sections of the text based on mismatches. Despite their efforts, including vectorization and loop unrolling, the author struggles to match grep's speed. Eventually, they discover that grep employs a "treacherous optimization" technique that sacrifices performance in worst-case scenarios for better average-case performance. By adopting a similar approach, the author manages to improve Hex Fiend's performance slightly, but they reflect on the trade-offs involved in such optimizations. The article concludes with a contemplation of whether the benefits of this optimization are worth the potential drawbacks in performance during less favorable conditions.
- The author aimed to optimize Hex Fiend's string searching to outperform grep.
- Initial attempts using the Boyer-Moore algorithm resulted in slower performance than grep.
- Grep's optimization technique improves average-case performance at the cost of worst-case performance.
- The author successfully implements a similar optimization, achieving a slight performance gain.
- The article raises questions about the value of optimization strategies that may compromise performance in certain scenarios.
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1 commentsThe Treacherous Optimization (2006) - https://news.ycombinator.com/item?id=21533301 - Nov 2019 (7 comments)
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