Struct MigrationState 

pub struct MigrationState {
    pub vshard_id: u16,
    pub source_group: u64,
    pub target_group: u64,
    pub source_node: u64,
    pub target_node: u64,
    pub phase: MigrationPhase,
    pub write_pause_budget_us: u64,
    pub started_at: Option<Instant>,
}

Full state of a vShard migration.

Fields

vshard_id: u16

vShard being migrated.

source_group: u64

Source Raft group.

target_group: u64

Target Raft group.

source_node: u64

Source node (current owner).

target_node: u64

Target node.

phase: MigrationPhase

Current phase.

write_pause_budget_us: u64

Maximum write-pause budget in microseconds.

started_at: Option<Instant>

When migration was initiated.

Implementations

impl MigrationState

pub fn new( vshard_id: u16, source_group: u64, target_group: u64, source_node: u64, target_node: u64, write_pause_budget_us: u64, ) -> Self

pub fn start_base_copy(&mut self, bytes_total: u64)

Start Phase 1: Base Copy.

pub fn update_base_copy(&mut self, bytes_transferred: u64)

Update base copy progress.

pub fn start_wal_catchup(&mut self, start_lsn: u64, source_lsn: u64)

Transition to Phase 2: WAL Catch-up.

pub fn update_wal_catchup(&mut self, current_lsn: u64, source_lsn: u64)

Update WAL catch-up progress.

pub fn is_catchup_ready(&self) -> bool

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

pub fn start_cutover(&mut self, estimated_pause_us: u64) -> Result<()>

Attempt to start Phase 3: Atomic Cut-over.

Returns Err if the estimated pause would exceed the budget.

pub fn complete(&mut self, actual_pause_us: u64)

Complete the migration.

pub fn fail(&mut self, reason: String)

Mark migration as failed. Source remains authoritative.

pub fn is_active(&self) -> bool

pub fn elapsed(&self) -> Option<Duration>

Elapsed time since migration started.

pub fn vshard_id(&self) -> u16

pub fn phase(&self) -> &MigrationPhase

Trait Implementations

impl Clone for MigrationState

fn clone(&self) -> MigrationState

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MigrationState

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

Formats the value using the given formatter.