Struct MaglevTable 

pub struct MaglevTable<N> { /* private fields */ }

Maglev consistent hashing table.

Generic over the node type N which must be Hash + Clone + Eq. The table provides O(1) primary lookups and preference-list queries for replica-aware routing.

Implementations

impl<N: Hash + Clone + Eq> MaglevTable<N>

pub fn new(nodes: Vec<N>) -> Self

Build a new Maglev table with default capacity (nodes.len() * 100, rounded up to the nearest prime).

pub fn with_capacity(nodes: Vec<N>, min_capacity: usize) -> Self

Build a new Maglev table with the given minimum capacity.

The actual table size will be the smallest prime ≥ min_capacity. When comparing tables across node set changes (e.g., measuring disruption), use the same capacity for both to ensure keys hash to the same slots.

pub fn get<K: Hash>(&self, key: &K) -> Option<&N>

O(1) lookup of the primary node for a key.

pub fn get_top_k<K: Hash>(&self, key: &K, k: usize) -> Vec<&N>

Return up to k distinct nodes in preference order for the given key.

The first element always matches get(key). Preference order is determined by walking the lookup table from the hashed slot and collecting unique nodes encountered. This ensures consistency with the primary lookup.

pub fn is_match<K: Hash>(&self, key: &K, node: &N, top_k: usize) -> bool

Returns true if node appears in the top-top_k entries of the preference list for key.

Note: when top_k >= self.len() the result is always true (every node appears exactly once in the full preference list). This method is most useful with small top_k values (e.g., checking if a node is one of the top-3 replicas for a key).

pub fn nodes(&self) -> &[N]

Return all nodes in the table.

pub fn capacity(&self) -> usize

Return the table size (the prime M).

pub fn len(&self) -> usize

Return the number of nodes.

pub fn is_empty(&self) -> bool

Return whether the table has no nodes.