Struct Cache

pub struct Cache { /* private fields */ }

Cache, in which blocks or blobs are cached in-memory after being retrieved from disk

This speeds up consecutive queries to nearby data, improving read performance for hot data.

Examples

Sharing cache between multiple trees

// Provide 40 MB of cache capacity
let cache = Arc::new(Cache::with_capacity_bytes(40 * 1_000 * 1_000));

let tree1 = Config::new(folder).use_cache(cache.clone()).open()?;
let tree2 = Config::new(folder).use_cache(cache.clone()).open()?;

Implementations

impl Cache

pub fn with_capacity_bytes(bytes: u64) -> Self

Creates a new block cache with roughly n bytes of capacity.

pub fn size(&self) -> u64

Returns the amount of cached bytes.

pub fn capacity(&self) -> u64

Returns the cache capacity in bytes.

pub fn len(&self) -> usize

Returns the number of cached blocks.

pub fn is_empty(&self) -> bool

Returns true if there are no cached blocks.