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Amdahl's law

What it is

Speedup = 1 / (s + p/N), where s is the serial fraction. Maximum speedup is 1/s no matter how many cores.

Where it lives

Parallelisation budgets. Why "make it parallel" doesn't scale forever.

The key insight

A 5% serial fraction caps speedup at 20×. Twice as many cores can give less than twice the throughput.

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Across the foundations

VI AEAD Cryptographic foundations VII P vs NP Computational complexity VII NP-completeness Computational complexity VII Approximation algorithms Computational complexity VII Reductions Computational complexity VIII Central Limit Theorem Statistics & inference VIII Hypothesis testing & p-values Statistics & inference VIII Confidence intervals Statistics & inference

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