Struct TreeNodeCache 

pub struct TreeNodeCache { /* private fields */ }

In-process LRU cache of TreeNode postcard-encoded bytes. Keyed by BLAKE3 hash; bytes-bounded eviction.

Caller wraps this in a Mutex for shared access. Single- owner hot loops can use it unsynchronised.

Implementations

impl TreeNodeCache

pub fn new() -> Self

Construct a cache with the default 64 MiB cap.

pub fn with_capacity_bytes(cap_bytes: usize) -> Self

Construct a cache with an explicit byte cap. cap_bytes == 0 disables caching — every get misses, every insert is a no-op. Useful for ablation testing or for callers that want explicit cache disable.

pub fn get(&mut self, hash: &[u8; 32]) -> Option<Bytes>

Look up hash. On hit, returns a Bytes clone of the cached entry (Bytes::clone is one atomic refcount bump, not a memcpy of the node payload) and promotes the entry to most-recently-used. On miss, returns None.

pub fn len(&self) -> usize

Number of entries currently cached.

pub fn is_empty(&self) -> bool

true iff no entries are cached.

pub fn bytes(&self) -> usize

Current total byte payload across all cached entries.

pub fn cap_bytes(&self) -> usize

Configured byte cap.

pub fn hits(&self) -> u64

Lifetime hit counter.

pub fn misses(&self) -> u64

Lifetime miss counter.

pub fn hit_ratio(&self) -> f64

Hit ratio in [0.0, 1.0], or 0.0 when no accesses have happened. Useful for operator dashboards.

pub fn clear(&mut self)

Drop every entry. Resets hit / miss counters.

pub fn remove(&mut self, hash: &[u8; 32])

Drop a single entry by hash. Used by the chunk-delete / GC sweep paths to keep the cache in sync with the on-disk chunk store: a manifest node whose chunk file just went away must not survive in cache, otherwise subsequent fetch_range walks descend through the cached node and only discover the missing chunks at the leaf, confusing operator error attribution. Cache integrity (bytes hash to key) is preserved either way — this fix is for error- path clarity, not for soundness.

No-op if the hash isn’t cached.

Trait Implementations

impl Debug for TreeNodeCache

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

Formats the value using the given formatter.

impl Default for TreeNodeCache

fn default() -> Self

Returns the “default value” for a type.