Struct GlobalReadWatermark 

pub struct GlobalReadWatermark { /* private fields */ }

A safe snapshot point for a globally consistent cross-range read: a commit watermark per (collection, range) that the read pins itself to.

This is the “explicit safe snapshot/watermark path” the issue requires before a cross-range read may claim to be consistent. A consistent read must find a watermark here for every range it touches; a missing entry means the snapshot does not cover that range and the read cannot be served consistently.

Implementations

impl GlobalReadWatermark

pub fn new() -> GlobalReadWatermark

pub fn with( self, collection: CollectionId, range_id: RangeId, watermark: CommitWatermark, ) -> GlobalReadWatermark

Pin range’s safe read point to watermark (builder form).

pub fn insert( &mut self, collection: CollectionId, range_id: RangeId, watermark: CommitWatermark, )

Record range’s safe read point.

pub fn covers( &self, collection: &CollectionId, range_id: RangeId, ) -> Option<CommitWatermark>

The pinned watermark for a range, or None if the snapshot does not cover it.

Trait Implementations

impl Clone for GlobalReadWatermark

fn clone(&self) -> GlobalReadWatermark

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for GlobalReadWatermark

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

Formats the value using the given formatter.

impl Default for GlobalReadWatermark

fn default() -> GlobalReadWatermark

Returns the “default value” for a type.

impl Eq for GlobalReadWatermark

impl PartialEq for GlobalReadWatermark

fn eq(&self, other: &GlobalReadWatermark) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for GlobalReadWatermark