Why 99% of C++ Microbenchmarks Lie - and How to Write the 1% that Matter!

Learn why most C++ microbenchmarks provide misleading results and discover how to create reliable performance measurements in this comprehensive conference talk from CppCon 2025. Explore the fundamental flaws in typical benchmarking approaches that focus solely on throughput while ignoring critical factors like branch prediction, cache effects, and pipeline stalls. Master the use of C++23 features including hardware performance counters, processor tracing, and machine code analysis to create meaningful benchmarks. Understand when and what to benchmark, distinguishing between latency and throughput measurements, and learn to choose appropriate tools for different scenarios. Examine real-world examples of deceptive benchmarks that appear to show optimizations but actually degrade performance in production environments. Gain practical skills in statistical analysis and visualization techniques to extract actionable insights from hardware performance data. Discover how to detect and eliminate misleading benchmark results while successfully transferring microbenchmarking insights to production code through top-down microarchitecture analysis and proper measurement methodologies.