Tag
flame-graphs
- Sep 15, 2026 Comparing Two Profiles to Find a Regression That Is Real A differential flame graph is a difference of two sample sets on a shared layout; the normalisation, the noise floor, and frame identity each decide whether a red bar means anything. performance engineering
- Sep 20, 2025 How Many Samples a Profile Needs Before Its Numbers Mean Anything Sampling profiles are binomial estimates, not measurements; the arithmetic that turns sample counts into confidence intervals, and the differences a run can actually resolve. performance engineering
- Sep 18, 2025 Merging Profiles Across a Fleet Without Losing the Tail Why summing per-host profiles answers a different question than profiling the fleet, how weight normalization changes the answer, and what a merged profile cannot tell you. observability
- Sep 22, 2024 Folded Stacks, Call Trees, and What Aggregation Destroys Two representations of the same samples, what each preserves, and why the choice determines whether a profile can be merged across hosts or read as a flame graph. observability
- Mar 1, 2023 Building a Flame Graph from a Set of Stack Samples Flame graphs are a sorted trie of stack prefixes; the merge, the sort, and the width computation each decide what the picture can and cannot show. performance engineering