Struct SizeTiered

pub struct SizeTiered {
    pub base_size: u32,
    pub level_ratio: u8,
}

Size-tiered compaction strategy (STCS)

If a level reaches a threshold, it is merged into a larger segment to the next level.

STCS suffers from high read and temporary doubled space amplification, but has good write amplification.

Fields

base_size: u32

Base size

level_ratio: u8

Size ratio between levels of the LSM tree (a.k.a fanout, growth rate).

This is the exponential growth of the from one level to the next

A level target size is: base_size * level_ratio.pow(#level + 1)

Implementations

impl Strategy

pub fn new(base_size: u32, level_ratio: u8) -> Self

Creates a new STCS strategy with custom base size

Trait Implementations

impl Clone for Strategy

fn clone(&self) -> Strategy

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl CompactionStrategy for Strategy

fn get_name(&self) -> &'static str

Gets the compaction strategy name.

fn choose(&self, levels: &LevelManifest, config: &Config) -> Choice

Decides on what to do based on the current state of the LSM-tree’s levels

impl Default for Strategy

fn default() -> Self

Returns the “default value” for a type.