Struct Fifo

pub struct Fifo {
    pub limit: u64,
    pub ttl_seconds: Option<u64>,
}

FIFO-style compaction

Limits the tree size to roughly limit bytes, deleting the oldest segment(s) when the threshold is reached.

Will also merge segments if the amount of segments in level 0 grows too much, which could cause write stalls.

Additionally, a (lazy) TTL can be configured to drop old segments.

Caution

Only use it for specific workloads where:

1. You only want to store recent data (unimportant logs, …)
2. Your keyspace grows monotonically (e.g. time series)
3. You only insert new data (no updates)

Fields

limit: u64

Data set size limit in bytes

ttl_seconds: Option<u64>

TTL in seconds, will be disabled if 0 or None

Implementations

impl Strategy

pub fn new(limit: u64, ttl_seconds: Option<u64>) -> Self

Configures a new Fifo compaction strategy

Trait Implementations

impl Clone for Strategy

fn clone(&self) -> Strategy

Returns a duplicate of the value.

const 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