Tag
cost-models
- Dec 1, 2025 Asymptotic Notation as Sets of Functions, Not Growth Rates Big-O names a set of functions fixed by a constant and a threshold. What those witnesses promise for two-input bounds, for logarithms, and for small n. algorithms
- Apr 2, 2025 Ranking Optimization Candidates by Expected Payoff How to combine a measured cost share, a realistic achievable factor, and the probability that a change survives review into one comparable score per candidate. performance engineering
- Mar 25, 2025 PRAM Variants and the Cost of Ignoring Memory What the EREW, CREW, and CRCW models permit, how work and depth carry over from the DAG, and why a model with free memory access mispredicts real parallel time. algorithms
- Nov 23, 2024 Removing Work Before Making It Faster Why eliminating an operation dominates optimizing it, how redundant computation and over-fetching hide in ordinary code, and what changes when work is removed rather than accelerated. performance engineering
- May 26, 2024 Amdahl's Law as a Ceiling on Optimization Returns How the fraction of time a change addresses bounds its total payoff, why the bound is a filter rather than a forecast, and where the fixed-workload assumption breaks. performance engineering
- Dec 27, 2023 Tile Selection: Cost Models Against Measurement A fused kernel still needs a tile shape and a loop order, and the compiler must choose them either by estimating cost or by measuring candidates on the device. inference systems
- Apr 7, 2023 Instruction Selection as Tree Tiling How a back end maps an intermediate representation onto machine instructions by covering expression trees with patterns, and why legality and cost are separate questions. compilers
- Jul 27, 2022 The Break-Even Hit Rate for Adding a Cache A cache costs a lookup on every access and pays back only on hits, which gives a hit-rate threshold below which the cache makes the system slower. performance engineering