Struct Prefetcher 

pub struct Prefetcher {
    pub strategy: PrefetchStrategy,
    /* private fields */
}

A prefetcher that warms a Cache based on the configured PrefetchStrategy.

Call trigger_prefetch each time a key is accessed; the prefetcher will synchronously insert placeholder entries for predicted future keys that are not already present.

Thread safety

Prefetcher is Clone and thread-safe when the inner cache is Send + Sync. The pending queue is protected by a Mutex.

Fields

strategy: PrefetchStrategy

Strategy driving key prediction.

Implementations

impl Prefetcher

pub fn new(strategy: PrefetchStrategy, cache: Arc<dyn Cache>) -> Self

Create a new Prefetcher with the given strategy and cache.

Uses a no-op loader that inserts empty-byte placeholder entries.

pub fn with_loader<F>( strategy: PrefetchStrategy, cache: Arc<dyn Cache>, loader: F, ) -> Self

where F: Fn(&str) -> Vec<u8> + Send + Sync + 'static,

Create a Prefetcher with a custom value loader function.

The loader receives the key and returns the bytes that should be stored in the cache for that key (e.g. reads from disk or network).

pub fn with_max_pending(self, max: usize) -> Self

Set the maximum number of pending prefetch requests.

pub fn trigger_prefetch(&self, current_key: &str)

Trigger a prefetch based on current_key.

Predicts the next keys using the configured strategy and immediately inserts them into the cache via the loader if they are not already present. Predictions that cannot be determined (e.g. key does not match the expected pattern) are silently ignored.

pub fn pending_count(&self) -> usize

Return the number of keys currently in the pending queue.

pub fn drain_pending(&self) -> Vec<String>

Drain the pending queue and return all queued keys.

This can be used by a background worker to post-process prefetch completions.

pub fn cache(&self) -> &Arc<dyn Cache>

Return a reference to the underlying cache.

Trait Implementations

impl Debug for Prefetcher

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

Formats the value using the given formatter.