Struct FrnIndex 

pub(super) struct FrnIndex {
    ids: Vec<EntryId>,
    covers: u32,
}

Fields

ids: Vec<EntryId>

EntryIds ordered by (masked record number, id). Appended entries always carry the largest ids, so equal keys read old-before-new.

covers: u32

Entries [0, covers) are represented; later ids are found by the tail scan until Self::merge_appended runs (end of USN batch).

Implementations

impl FrnIndex

pub(super) fn build(frn: &[u64], flag: &[u8]) -> Self

Build from scratch over every live entry (initial scan finish, snapshot restore).

pub(super) fn lookup( &self, key: RecordNo, frn: &[u64], flag: &[u8], ) -> Option<EntryId>

The live entry for key (a record number), if any.

pub(super) fn merge_appended(&mut self, frn: &[u64], flag: &[u8])

Fold the appended entries into sorted order — live ones only; anything tombstoned before its first merge can never be looked up again. In place: each batch pair binary-searches its insertion point and the segments between insertion points move once (copy_within) — O(batch·log n) comparisons, no reallocation (ADR-0008). Equal keys keep old-before-new order; liveness never depends on that order anyway (at most one live pair per key).

pub(super) fn compact(&self, remap: &[EntryId], new_len: u32) -> Self

Remapped copy for compaction: dead ids drop out, survivors renumber. Keys (masked record numbers) are copied unchanged by the caller and the remap preserves relative id order, so the (key, id) order — and with it lookup’s binary search — survives without a re-sort.

pub(super) const fn bytes(&self) -> u64

pub(super) fn shrink_to_fit(&mut self)

Trait Implementations

impl Default for FrnIndex

fn default() -> FrnIndex

Returns the “default value” for a type.