lemire.me/blog/2026/10/26/billion-query-per-second-lookup-tables-in-c Billion-query-per-second lookup tables in C++
A header-only C++23 library builds perfect hash tables at compile time, using a gperf-style association table plus SIMD key comparison. Lookups cost about 5 cycles, roughly 1.3 ns, versus 16.6 ns for std::unordered_map and 7.7 ns for gperf on HTTP header names.
— via Daniel Lemire, Daniel Lemire
