this post was submitted on 30 May 2024
16 points (100.0% liked)

C++

2227 readers
10 users here now

The center for all discussion and news regarding C++.

Rules

founded 2 years ago
MODERATORS
farados@vlemmy.net
Nihili0@programming.dev
lysdexic@programming.dev
16
An Extensive Benchmark of C and C++ Hash Tables | A comparative, extendible benchmarking suite for C and C++ hash-table libraries. (jacksonallan.github.io)
submitted 2 years ago by deadcream@sopuli.xyz to c/cpp@programming.dev
3 comments fedilink hide all child comments
top 3 comments
sorted by: hot top controversial new old
[–] deadcream@sopuli.xyz 6 points 2 years ago (1 children)

tl;dr:

std::unordered_map is one of the worst ones, boost::unordered_flat_map and absl::flat_hash_map are one of the best.

[–] lysdexic@programming.dev 2 points 2 years ago (1 children)

std::unordered_map is one of the worst ones

It should be noted that the benchmark focused on the std::unordered_map implementation from GCC 13.2.0. I'm not sure if/how this conclusion can be extended to other implementations such as msvc or clang.

[–] deadcream@sopuli.xyz 4 points 2 years ago

Well the author claims that it's not possible for std::unordered_map to get close to other implementations because of constraints that the standard imposes on it. I.e. faster implementations simply behave slightly differently (in ways that are not important to most users).