boost::unordered map is a new king of data structures

This page summarizes the projects mentioned and recommended in the original post on /r/cpp

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SaaSHub helps you find the best software and product alternatives
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  1. STC

    A modern, user friendly, generic, type-safe and fast C99 container library: String, Vector, Sorted and Unordered Map and Set, Deque, Forward List, Smart Pointers, Bitset and Random numbers. (by stclib)

    When I developed CMAP, (unordered map in C), I made a benchmark comparing with a number of C++ hash maps, and they all perform 2-4 times faster than std::unordered_map. Tessil robin-map is the fastest overall here.

  2. InfluxDB

    InfluxDB – Built for High-Performance Time Series Workloads. InfluxDB 3 OSS is now GA. Transform, enrich, and act on time series data directly in the database. Automate critical tasks and eliminate the need to move data externally. Download now.

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  3. Klib

    A standalone and lightweight C library

  4. parallel-hashmap

    A family of header-only, very fast and memory-friendly hashmap and btree containers.

  5. flat_hash_map

    A very fast hashtable

  6. robin-hood-hashing

    Discontinued Fast & memory efficient hashtable based on robin hood hashing for C++11/14/17/20

  7. Hopscotch map

    C++ implementation of a fast hash map and hash set using hopscotch hashing

  8. robin-map

    C++ implementation of a fast hash map and hash set using robin hood hashing

  9. SaaSHub

    SaaSHub - Software Alternatives and Reviews. SaaSHub helps you find the best software and product alternatives

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  10. unordered_dense

    A fast & densely stored hashmap and hashset based on robin-hood backward shift deletion

    or martinus's https://github.com/martinus/unordered_dense

  11. map_benchmark

    Comprehensive benchmarks of C++ maps

    I've implemented this PoolAllocator which does exactly this: https://github.com/martinus/map_benchmark/blob/master/src/app/pool.h

  12. unordered

    Boost.org unordered module

    Here are the results of our uint32.cpp synthetic benchmark under VS2022 Release x64:

NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.

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