Struct S3FifoCache 

pub struct S3FifoCache<K, V, S = RandomState> { /* private fields */ }

A sharded, weighted, thread-safe S3-FIFO cache backed directly by quick_cache.

Implementations

impl<K, V, S> S3FifoCache<K, V, S>

pub const DEFAULT_SHARDS: usize = 256

Default power-of-two shard count used by S3FifoCache::new.

impl<K, V> S3FifoCache<K, V, RandomState>

where K: Eq + Hash + Clone, V: CacheEntry + Clone,

pub fn new(total_capacity_bytes: usize) -> Self

Creates a cache with Self::DEFAULT_SHARDS shards.

pub fn with_shards(total_capacity_bytes: usize, num_shards: usize) -> Self

Creates a cache with an explicit shard count.

Panics

Panics if num_shards == 0 or if num_shards is not a power of two.

impl<K, V, S> S3FifoCache<K, V, S>

where K: Eq + Hash + Clone, V: CacheEntry + Clone, S: BuildHasher + Clone,

pub fn with_hasher( total_capacity_bytes: usize, num_shards: usize, hash_builder: S, ) -> Self

Creates a cache with an explicit shard count and hash builder.

Because quick_cache uses equal-capacity shards internally, the actual backend capacity may round up when total_capacity_bytes is not evenly divisible by num_shards.

Panics

Panics if num_shards == 0 or if num_shards is not a power of two.

pub fn insert(&self, key: K, value: V)

Inserts or replaces key with value.

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

Looks up key and returns a clone of the stored value.

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

Removes key if present and returns the removed value.

pub fn remove_if<F>(&self, predicate: F)

where F: Fn(&K) -> bool,

Removes all entries matching predicate and returns the number removed.

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

Returns true if key is currently present.

pub fn len(&self) -> usize

Returns the current number of live entries.

pub fn total_charge(&self) -> usize

Returns the current total weighted charge.

pub fn total_capacity(&self) -> usize

Returns the backend’s configured total weighted capacity.

This may be larger than the requested constructor argument when the requested total capacity is not evenly divisible across shards.

pub fn shard_count(&self) -> usize

Returns the number of backend shards.

Trait Implementations

impl<K, V, S> BufferCache<K, V> for S3FifoCache<K, V, S>

where K: Eq + Hash + Clone + Send + Sync + 'static, V: CacheEntry + Clone + Send + Sync + 'static, S: BuildHasher + Clone + Send + Sync + 'static,

fn as_any(&self) -> &dyn Any

Returns this backend as Any for backend-specific downcasts.

fn strategy(&self) -> BufferCacheStrategy

Returns the eviction strategy used by this cache.

fn insert(&self, key: K, value: V)

Inserts or replaces key with value.

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

Looks up key and returns a clone of the stored value.

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

Removes key if it is present and returns the removed value.

fn remove_if(&self, predicate: &dyn Fn(&K) -> bool)

Removes every entry whose key matches predicate.

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

Returns true if key is currently resident.

fn len(&self) -> usize

Returns the number of resident entries.

fn total_charge(&self) -> usize

Returns the total resident weight.

fn total_capacity(&self) -> usize

Returns the configured total weight capacity.

fn shard_count(&self) -> usize

Returns the number of shards used by this backend.

fn is_empty(&self) -> bool

Returns true if the cache has no resident entries.