Struct GhostTable 

pub struct GhostTable { /* private fields */ }

Ghost table for a single vShard.

Tracks ghost stubs left behind after node migration. The anti-entropy sweeper runs periodically to purge stale ghosts.

Implementations

impl GhostTable

pub fn new() -> Self

pub fn insert(&mut self, stub: GhostStub)

Insert a ghost stub after a node is migrated away.

pub fn get(&self, node_id: &str) -> Option<&GhostStub>

Look up a ghost stub by node ID.

pub fn decrement_ref(&mut self, node_id: &str) -> bool

Decrement refcount for a ghost (when a local edge is deleted). Returns true if the ghost was purged (refcount reached zero).

pub fn increment_ref(&mut self, node_id: &str)

Increment refcount for a ghost (when a local edge to a ghost node is added).

pub fn sweep<F>(&mut self, verify_fn: F) -> SweepReport

where F: Fn(&str, u16) -> SweepVerdict,

Run anti-entropy sweep.

For each ghost stub, the caller must verify against the target shard:

1. Does the target shard acknowledge the node exists?
2. Do any local edges still reference this ghost?

verify_fn takes (node_id, target_shard) and returns SweepVerdict. The sweeper runs at lowest I/O priority and is rate-limited.

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn total_purged(&self) -> u64

pub fn last_sweep_ms(&self) -> u64

pub fn stubs(&self) -> impl Iterator<Item = &GhostStub>

All ghost stubs (for metrics/debugging).

pub fn resolve(&self, node_id: &str) -> Option<u16>

Resolve a node lookup: if the node is a ghost, return the target shard for scatter-gather. Otherwise return None.

impl GhostTable

pub fn to_bytes(&self) -> Vec<u8>

Serialize all ghost stubs for persistence.

Returns MessagePack bytes that can be stored in the cluster catalog.

pub fn from_bytes(data: &[u8]) -> Option<Self>

Restore ghost stubs from persisted bytes.

Called on startup to recover ghost state from the cluster catalog.

Trait Implementations

impl Clone for GhostTable

fn clone(&self) -> GhostTable

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for GhostTable

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

Formats the value using the given formatter.

impl Default for GhostTable

fn default() -> Self

Returns the “default value” for a type.