Struct AdaptiveLoadBalancer 

pub struct AdaptiveLoadBalancer {
    pub algorithm: LbAlgorithm,
    pub peers: Vec<LbPeer>,
    pub rr_index: usize,
    pub virtual_nodes: usize,
    pub total_requests: u64,
    pub total_errors: u64,
    /* private fields */
}

Production-grade, multi-algorithm load balancer with dynamic weight adjustment and consistent-hash support.

Fields

algorithm: LbAlgorithm

Active routing algorithm.

peers: Vec<LbPeer>

Ordered list of registered peers (insertion order is preserved).

rr_index: usize

Round-robin cursor (index into peers after filtering healthy ones).

virtual_nodes: usize

Number of virtual nodes per peer in the consistent-hash ring.

total_requests: u64

Total requests successfully routed by this balancer instance.

total_errors: u64

Total errors recorded via record_completion.

Implementations

impl AdaptiveLoadBalancer

pub fn new(algorithm: LbAlgorithm) -> Self

Creates a new, empty balancer using the given algorithm. virtual_nodes defaults to 150.

pub fn add_peer(&mut self, peer: LbPeer)

Register a peer. If a peer with the same id already exists it is replaced with the new record.

pub fn remove_peer(&mut self, peer_id: &str) -> bool

Remove a peer by id. Returns true if the peer was found and removed.

pub fn select(&mut self, request: &LbRequest, now: u64) -> Option<LbDecision>

Route a request to the best available peer.

Returns None when no healthy peers are available.

pub fn record_connection_start(&mut self, peer_id: &str) -> bool

Increment active_connections for a peer. Returns false if unknown.

pub fn record_completion( &mut self, peer_id: &str, latency_ms: f64, success: bool, _now: u64, ) -> bool

Record completion of a request.

• Decrements active_connections (saturating at 0).
• Updates avg_latency_ms with EMA alpha = 0.2.
• Increments total_errors (per-peer and global) on failure.

Returns false when the peer is not registered.

pub fn mark_healthy(&mut self, peer_id: &str, healthy: bool) -> bool

Set a peer’s healthy flag. Returns false if the peer is unknown.

pub fn adjust_weights_by_latency(&mut self)

Auto-tune weights based on current latency estimates.

Formula: weight[i] = max(1, round(1000.0 / avg_latency_ms)) Peers with avg_latency_ms == 0 are skipped (latency not yet measured).

pub fn healthy_peers(&self) -> Vec<&LbPeer>

Returns references to all healthy peers.

pub fn peer_count(&self) -> usize

Total number of registered peers.

pub fn healthy_peer_count(&self) -> usize

Number of healthy peers.

pub fn stats(&self) -> AdaptiveLbStats

Aggregate statistics snapshot.