Struct RollbackPlan 

pub struct RollbackPlan {
    pub recover_to_lsn: u64,
    pub local_frontier: u64,
    pub commit_watermark: u64,
    pub tail_lsns: u64,
}

The computed, side-effect-free rollback plan. Splitting this out lets the boundary invariant be asserted without driving any transport.

Fields

recover_to_lsn: u64

The recover-to-LSN target: the common point with the new primary.

local_frontier: u64

The deposed primary’s local frontier (inclusive tail upper bound).

commit_watermark: u64

The commit watermark — the durable floor that bounds the recover target from below.

tail_lsns: u64

Number of LSNs the tail spans (local_frontier - recover_to_lsn).

Implementations

impl RollbackPlan

pub fn compute(req: &RollbackRequest) -> Result<RollbackPlan, RollbackError>

Compute and validate the rollback plan for req.

Enforces the hard invariant: the recover target (common point) must be at or above the commit watermark, so nothing at or below the watermark is ever rolled back. A common point below the watermark means the election handed us a target that would discard committed data — a contract violation we refuse rather than honour.

pub fn has_divergent_tail(&self) -> bool

Whether there is a divergent tail to roll back. When the local frontier is at or below the common point the node is already on the shared timeline and only needs to rejoin.

Trait Implementations

impl Clone for RollbackPlan

fn clone(&self) -> RollbackPlan

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for RollbackPlan

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

Formats the value using the given formatter.

impl Eq for RollbackPlan

impl PartialEq for RollbackPlan

fn eq(&self, other: &RollbackPlan) -> 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 RollbackPlan