congee
Congee
A Rust implementation of ART-OLC concurrent adaptive radix tree. It implements the optimistic lock coupling with proper SIMD support.
It only supports (and is optimized for) 8 byte key; due to this specialization, congee has great performance – basic operations are faster than most hash tables, range scan is an order of magnitude faster.
| The code is extensively tested with [{address | leak} sanitizer](https://doc.rust-lang.org/beta/unstable-book/compiler-flags/sanitizer.html) as well as libfuzzer. |
Why Congee?
- Fast performance, faster than most hash tables.
- Concurrent, super scalable, it reaches 150Mop/s on 32 cores.
- Super low memory consumption. Hash tables often have exponential bucket size growth, which often lead to low load factors. ART is more space efficient.
Why not Congee?
- Not for arbitrary key size. This library only supports 8 byte key.
Example:
use congee::Art;
let art = Art::new();
let guard = art.pin(); // enter an epoch
art.insert(0, 42, &guard); // insert a value
let val = art.get(&0, &guard).unwrap(); // read the value
assert_eq!(val, 42);
let mut scan_buffer = vec![(0, 0); 8];
let scan_result = art.range(&0, &10, &mut scan_buffer, &guard); // scan values
assert_eq!(scan_result, 1);
assert_eq!(scan_buffer[0], (0, 42));
History
Congee was originally developed in the Alchemy project to fullfil its need for a concurrent, scalable, and low memory footprint range index.