Trait MergePolicy 

pub trait MergePolicy: Send + Debug {
    // Required method
    fn select_merge(&self, candidates: &[PathBuf]) -> Result<Vec<PathBuf>>;
}

Trait for merge policy implementations (M5.2, Issue #383)

A merge policy decides which SSTables should be compacted together. This trait allows different compaction strategies (STCS, LCS, TWCS, etc.) to be plugged into the WriteEngine.

Required Methods

fn select_merge(&self, candidates: &[PathBuf]) -> Result<Vec<PathBuf>>

Select SSTables for the next compaction

Arguments

• candidates - Available SSTable paths in the data directory

Returns

Paths to SSTables that should be merged, ordered newest to oldest. Returns empty Vec if no compaction is needed.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl MergePolicy for STCSPolicy

Available on crate feature write-support only.