Struct lsm_tree::BlockCache

pub struct BlockCache { /* private fields */ }

Block cache, in which blocks 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 block cache between multiple trees

use lsm_tree::{Tree, Config, BlockCache};
use std::sync::Arc;

// Provide 10'000 blocks (10'000 * 4 KiB = 40 MB) of cache capacity
let block_cache = Arc::new(BlockCache::with_capacity_blocks(10_000));

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

Implementations

impl BlockCache

pub fn with_capacity_blocks(n: usize) -> Self

Creates a new block cache with roughly n blocks of capacity

Multiply n by the block size to get the approximate byte count

pub fn len(&self) -> usize

Returns the number of cached blocks

Multiply n by the block size to get the approximate byte count

pub fn is_empty(&self) -> bool

Returns true if there are no cached blocks