Method is_catchup_ready

nodedb-cluster/src/migration.rs:144–156

Check if WAL lag is low enough to proceed to cut-over.

(&self)

    /// Check if WAL lag is low enough to proceed to cut-over.
    pub fn is_catchup_ready(&self) -> bool {
        if let MigrationPhase::WalCatchUp {
            current_lsn,
            source_lsn,
            ..
        } = self.phase
        {
            // Sub-millisecond lag = within 10 LSN entries.
            source_lsn.saturating_sub(current_lsn) <= 10
        } else {
            false
        }
    }

    /// Attempt to start Phase 3: Atomic Cut-over.
    ///