Struct SemanticEmbeddingCache 

pub struct SemanticEmbeddingCache { /* private fields */ }

A tick-based embedding cache with LRU batch eviction and TTL expiry.

Implementations

impl SemanticEmbeddingCache

pub fn new(config: EmbeddingCacheConfig) -> Self

Create a new cache with the given configuration.

pub fn put(&mut self, key: &str, embedding: Vec<f64>, ttl: Option<u64>)

Insert an embedding into the cache.

If ttl is None the default TTL from the config is used. When the cache exceeds max_entries after insertion the least-recently used entries (by access_count, then oldest computed_tick) are evicted in a batch.

pub fn get(&mut self, key: &str) -> Option<&[f64]>

Retrieve the embedding for key if it exists and has not expired.

Increments the entry’s access_count and records a hit. Returns None (and records a miss) when the key is absent or the entry has expired.

pub fn contains(&self, key: &str) -> bool

Check whether key is present and not expired without updating the entry’s access_count.

pub fn invalidate(&mut self, key: &str) -> bool

Remove a specific entry. Returns true if the entry existed.

pub fn invalidate_prefix(&mut self, prefix: &str) -> usize

Remove all entries whose key starts with prefix. Returns the number of entries removed.

pub fn tick_cleanup(&mut self)

Advance the internal tick counter by one and remove all expired entries.

pub fn entry_count(&self) -> usize

Return the current number of entries in the cache.

pub fn hit_rate(&self) -> f64

Return the hit rate as a value in [0.0, 1.0].

Returns 0.0 when no lookups have been performed.

pub fn memory_estimate(&self) -> usize

Estimate the memory footprint of all cached entries in bytes.

Each entry contributes key.len() + embedding.len() * 8 bytes (the heap portion of the key string plus the heap portion of the Vec<f64>).

pub fn stats(&self) -> EmbeddingCacheStats

Return a snapshot of the cache statistics.