Struct PlanCache 

pub struct PlanCache { /* private fields */ }

LRU plan cache with TTL-based expiry

Implements a manual LRU cache using a HashMap for O(1) lookups and a VecDeque to track access order for eviction. Thread-safe via parking_lot::Mutex.

Implementations

impl PlanCache

pub fn new(config: PlanCacheConfig) -> Self

Create a new plan cache with the given configuration

pub fn get(&self, key: &CacheKey) -> Option<PhysicalPlan>

Look up a cached plan by its cache key.

Returns Some(PhysicalPlan) if a fresh (non-expired) entry exists, otherwise returns None. Updates LRU order and hit/miss statistics.

pub fn insert( &self, key: CacheKey, plan: PhysicalPlan, normalized_query: String, )

Insert a plan into the cache, evicting the LRU entry if at capacity.

pub fn invalidate_all(&self)

Invalidate all cached plans

pub fn invalidate_prefix(&self, prefix: &str)

Invalidate all cached plans whose normalized query starts with the given prefix (e.g., a collection name).

pub fn cache_stats(&self) -> CacheStats

Return a snapshot of the current cache statistics

Trait Implementations

impl Debug for PlanCache

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

Formats the value using the given formatter.