S3-FIFO Cache
This library contains an implementation for a non-thread-safe S3-FIFO cache as per the paper at https://jasony.me/publication/sosp23-s3fifo.pdf
Here is the abstract from the paper.
As a cache eviction algorithm, FIFO has a lot of attractive properties, such as simplicity, speed, scalability, and flash- friendliness. The most prominent criticism of FIFO is its low efficiency (high miss ratio). In this work, we demonstrate a simple, scalable FIFO- based algorithm with three static queues (S3-FIFO). Evalu- ated on 6594 cache traces from 14 datasets, we show that S3- FIFO has lower miss ratios than state-of-the-art algorithms across traces. Moreover, S3-FIFO’s efficiency is robust — it has the lowest mean miss ratio on 10 of the 14 datasets. FIFO queues enable S3-FIFO to achieve good scalability with 6× higher throughput compared to optimized LRU at 16 threads. Our insight is that most objects in skewed workloads will only be accessed once in a short window, so it is critical to evict them early (also called quick demotion). The key of S3-FIFO is a small FIFO queue that filters out most objects from entering the main cache, which provides a guaranteed demotion speed and high demotion precision.
use ;
// The cached value must be Clone.
// Hash is optional and allows using the S3FIFOKey struct
// Create a cache with a capacity of 128 (small: 12, main: 115, ghost: 115)
let mut cache = S3FIFO new;
let value = Foobar ;
let key = new;
// Check if the item is in the cache before inserting
if let None = cache.get
// If your value is not Hash, then supply a key yourself that implements PartialEq
// let mut hash_cache: S3FIFO<S3FIFOKey<Foobar>, Foobar> = S3Fifo::new(1234);
let mut custom_cache: = new
cache.put;
cache.get;