KLklaussilveira·Nov 24, 2025Submission
Libcuckoo: A high-performance, concurrent hash table
3 points · Open discussionefficient
libcuckoo
C++2016–2025
efficient / libcuckoo
libcuckoo
A high-performance, concurrent hash table
6Distinct people
6Mentions
0Explicit recommenders
1.8KGitHub stars
What to know before exploring
What it is
A high-performance, concurrent hash table
GitHub
Where it is used
No documented product use has been verified yet.
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This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 12:54:37 PM UTC.
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Mentions over time
HN mentions by year6 dated mentions
Observed mentions: 2016-05-01 18:25:50 UTC to 2025-11-24 21:25:28 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2016 | 2016-01-01 00:00:00 UTC | 2017-01-01 00:00:00 UTC | 1 | 1 | 0 |
| 2017 | 2017-01-01 00:00:00 UTC | 2018-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2018 | 2018-01-01 00:00:00 UTC | 2019-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2019 | 2019-01-01 00:00:00 UTC | 2020-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2020 | 2020-01-01 00:00:00 UTC | 2021-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 1 | 1 | 0 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 1 | 1 | 0 |
What Hacker News says
6 sourcesLibcuckoo: A high-performance concurrent hash table
1 points · Open discussionhttps://github.com/efficient/libcuckoo
There's the related cuckoo filter as well: https://github.com/efficient/cuckoofilter
In Why Hashbrown Does a Double Lookuphttps://blog.acolyer.org/2016/11/03/algorithmic-improvements...
https://github.com/efficient/libcuckoo
In Why Hashbrown Does a Double LookupOne nit, as one of the authors of libcuckoo: Of the tested tables, libcuckoo is the only one that's a concurrent hash table. I'm glad that without modification, our single-threaded performance is still doing well, but this isn't the primary use case of libcuckoo.
If you want to compare it against a thread-unsafe table, it's a bit more honest to use the locked_table class, which grants ownership to all locks in the table in advance. It's a fair bit faster.
It doesn't change the memory use - I've created a stripped-down version in the past that elides all the locks, which is better for memory efficiency - but that's not really our goal.
For more on using the locked_table interface, see: https://github.com/efficient/libcuckoo/blob/master/tests/uni...
(Also, for hashing strings, please make sure you've got libcuckoo configured to use city
Read the rest
hash for string hashing, as you had "opic", to make the comparison equivalent.)
In fairness to the OP, however, it's worth noting that this is a pretty new addition to libcuckoo (February), and we haven't documented or pushed it hard.
Libcuckoo – high-performance, concurrent hash table
1 points · Open discussion