Struct DefragOptions 

#[non_exhaustive]
pub struct DefragOptions {
    pub sparse_threshold: f64,
    pub max_values: usize,
}

Knobs for a defrag pass.

sparse_threshold: fill-density fraction (live_slots / stored_slots) below which a page is treated as sparse and its values are relocated (e.g. 0.25 = pages less than 25% dense are compacted). Consumed by TransactionManager::sparse_data_pages during step 2 of the sweep. Dense pages above the threshold are left alone — per R3, the cost of re-packing a mostly-full page exceeds the benefit. Values <= 0 disable the sweep entirely (the sparse set comes back empty).

max_values: soft cap on work per call, so a very large database can be defragged incrementally across several transactions. 0 means no limit. The cap counts values relocated, not pages touched. Breaking the loop early leaves the transaction in a valid state; the caller chooses commit vs rollback.

I36 (ISSUES.md, 2026-05-22): #[non_exhaustive] so a future tuning knob (e.g. a per-page time cap, a pages-vs-values-priority toggle) is not a breaking change. External callers construct via DefragOptions { ..Default::default() } rather than a full struct literal.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

sparse_threshold: f64

max_values: usize

Implementations

impl DefragOptions

pub fn sparse_threshold(self, threshold: f64) -> Self

pub fn max_values(self, cap: usize) -> Self

Trait Implementations

impl Clone for DefragOptions

fn clone(&self) -> DefragOptions

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DefragOptions

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for DefragOptions

fn default() -> DefragOptions

Returns the “default value” for a type.