Struct S3Fifo 

pub struct S3Fifo<K, V> { /* private fields */ }

S3-FIFO cache with scan-resistant eviction.

Implementations

impl<K, V> S3Fifo<K, V>

where K: Hash + Eq + Clone,

pub fn new(capacity: usize) -> Self

Create a new S3-FIFO cache with the given total capacity.

The capacity is split: 10% small, 90% main. Ghost capacity matches small capacity. Minimum total capacity is 2.

pub fn get(&mut self, key: &K) -> Option<&V>

Look up a value by key, incrementing the frequency counter on hit.

pub fn insert(&mut self, key: K, value: V) -> Option<V>

Insert a key-value pair. Returns the evicted value if an existing entry with the same key was replaced.

pub fn remove(&mut self, key: &K) -> Option<V>

Remove a key from the cache.

pub fn len(&self) -> usize

Number of entries in the cache.

pub fn is_empty(&self) -> bool

Whether the cache is empty.

pub fn capacity(&self) -> usize

Total capacity.

pub fn stats(&self) -> S3FifoStats

Cache statistics.

pub fn clear(&mut self)

Clear all entries and reset statistics.

pub fn contains_key(&self, key: &K) -> bool

Check if the cache contains a key (without incrementing freq).

Trait Implementations

impl<K, V> Debug for S3Fifo<K, V>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.