Benchmarking Perfect Hashing in C++
Benchmarking perfect hashing functions in C++ using clang++-19 and g++-13 reveals mph as the fastest with limitations. Various hash function implementations are compared for lookup time, build time, and size, aiding system optimization.
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The provided information discusses benchmarking perfect hashing functions in C++ using various compilers like clang++-19 and g++-13 with different optimization flags. The benchmarks cover different hash function implementations like if_else, switch_case, map, unordered_map, boost_unordered_flat_map, gperf, frozen, and mph, each with its characteristics and performance considerations. The measurements include lookup time, build time, and binary size for different scenarios like integer to integer and string_view to integer mappings. Additionally, the parameters affecting the benchmarks, such as element size, range, length, probability, and seed, are detailed. The fastest lookup is achieved with mph, although it has specific limitations and hardware requirements. The summary also includes code snippets for mph lookup and find functions with corresponding assembly code snippets for g++. The information provides insights into optimizing system configurations for running benchmarks efficiently.
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