--- title: Principles of Mechanical Sympathy | daily.dev description: Mechanical sympathy is the practice of writing software that works with hardware rather than against it. Four core principles are covered: predictable... canonical: https://daily.dev/posts/principles-of-mechanical-sympathy-ktcus6sk5 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Principles of Mechanical Sympathy | daily.dev og:description: Mechanical sympathy is the practice of writing software that works with hardware rather than against it. Four core principles are covered: predictable... og:url: https://daily.dev/posts/principles-of-mechanical-sympathy-ktcus6sk5 og:image: https://api.daily.dev/og/posts/KTcUs6sk5.png og:image:alt: Principles of Mechanical Sympathy og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Principles of Mechanical Sympathy **[Martin Fowler](https://daily.dev/sources/mafo)** · 10 min read · 0 upvotes · 0 comments ## Summary Mechanical sympathy is the practice of writing software that works with hardware rather than against it. Four core principles are covered: predictable sequential memory access (which leverages CPU prefetching), cache line awareness and false sharing (padding variables to avoid contention between threads), the single-writer principle (dedicating one thread per resource to eliminate mutex overhead and enable batching), and natural batching (greedily building batches as data arrives rather than waiting for fixed timeouts or sizes). A practical example of an AI text embedding service illustrates how these principles combine to eliminate head-of-line blocking and improve throughput. The article also emphasizes measuring performance before optimizing. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [The Renaissance, Mechanical Sympathy, and AI Agents](https://daily.dev/posts/the-renaissance-mechanical-sympathy-and-ai-agents-9xgejfdek) · Nx · 2 upvotes · 1 comments - [Hardware Stockholm Syndrome](https://daily.dev/posts/hardware-stockholm-syndrome-wxlbuyh4z) · Hacker News · 2 upvotes · 1 comments - [The Automation of Empathy: How Do You Technically Build Simulated Empathy?](https://daily.dev/posts/the-automation-of-empathy-how-do-you-technically-build-simulated-empathy--7pbluivao) · Codemotion · 0 upvotes · 0 comments - [Software Engineering Principles Help Get More out of AI](https://daily.dev/posts/software-engineering-principles-help-get-more-out-of-ai-g2d3tqsex) · Telerik · 0 upvotes · 0 comments --- Tags: [#performance](https://daily.dev/tags/performance) [View this post on daily.dev](https://daily.dev/posts/principles-of-mechanical-sympathy-ktcus6sk5) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Principles of Mechanical Sympathy","url":"https://daily.dev/posts/principles-of-mechanical-sympathy-ktcus6sk5","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/principles-of-mechanical-sympathy-ktcus6sk5"},"datePublished":"2026-04-07T13:48:44.354Z","dateModified":"2026-04-07T13:49:15.118Z","description":"Mechanical sympathy is the practice of writing software that works with hardware rather than against it. 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