Jon Chery
496303471d
---ci--- project: atelier phase: 7 milestone: v0.1 status: complete phase_role: final milestone_complete: true requirements: covered: [ATELIER-01, ATELIER-02, ATELIER-03, ATELIER-04, ATELIER-05, ATELIER-06, ATELIER-07, ATELIER-08, ATELIER-09, ATELIER-10, ATELIER-11, ATELIER-12, ATELIER-13, ATELIER-14, ATELIER-15, ATELIER-16, ATELIER-17, ATELIER-18, ATELIER-19, ATELIER-20, ATELIER-21, ATELIER-22, ATELIER-23, ATELIER-24, ATELIER-25, ATELIER-26, ATELIER-27, ATELIER-28, ATELIER-29, ATELIER-30, ATELIER-31, ATELIER-32, ATELIER-33, ATELIER-34, ATELIER-35] partial: [] ship: milestone: v0.1 type: NFR tag: v0.0.7 merge: milestone/v0.1-atelier -> main release: https://git.cloudinit.dev/cloudinit-bot/atelier/releases/tag/v0.0.7 ---/ci--- Milestone v0.1 — Initial Framework (NFR, complete). 8 core principles (C1-C8), 11 domains, 110 domain principles, 27 derived docs, 4 good + 3 bad examples, 4 language docs, full matrix, 3 review docs. All 35 requirements covered. 7 patches (v0.0.0 pre-execution through v0.0.7 final). v0.0.7 IS the v0.1.0 milestone release.
40 lines
1.1 KiB
Markdown
40 lines
1.1 KiB
Markdown
# Performance — First Principles
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## 1. The Principles
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### P1. Measure First
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No optimization without measurement. Intuition about performance is
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usually wrong.
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### P2. Critical Path Focus
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Optimize what users actually wait for. The 95th percentile matters
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more than the average.
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### P3. Complexity Awareness
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Algorithmic cost is known. Big-O is a design conversation, not an
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afterthought.
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### P4. Resource Bounds
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Memory, CPU, I/O, network — all bounded. Unbounded growth is a bug.
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### P5. Caching with Intent
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Cache what is expensive, stable, and read often. Invalidation is
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designed, not bolted on.
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### P6. Lazy by Default
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Compute only when needed. Pay only for what is used.
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### P7. Async When Independent
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Work that does not depend on other work runs in parallel.
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### P8. Budget Discipline
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Performance is a design constraint. The budget is set, not negotiated
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after the fact.
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### P9. Perceived Performance
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What the user feels is what matters. A 200ms perceived response beats
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a 50ms measured one with no feedback.
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### P10. Regression Prevention
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Performance tests catch what functional tests miss. The slow path
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is tested as a path. |