Load Balancer
Compare round-robin, least-connections, weighted, and random across backend nodes.
Requests
0
Imbalance
0%
Nodes
4
Slow node
Off
Requests per node
Node 00 · 0.0 inflight
Node 10 · 0.0 inflight
Node 20 · 0.0 inflight
Node 30 · 0.0 inflight
Imbalance is the coefficient of variation of per-node load — 0% is perfectly even. Least-connections and weighted usually beat round-robin once a backend is slow or unevenly weighted.
How this simulator works
A load balancer spreads requests across backends. Round-robin is simple and even; least-connections avoids the busiest node; weighted honors capacity; random is cheap but noisy.
When algorithms differ
- Round-robin and random ignore backend load — turn on the slow node to see them pile work onto it.
- Least-connections routes to the node with the fewest in-flight requests, so it steers around the slow node.
- Weighted divides work in proportion to each node’s weight (here, weight = index + 1).
Reading the bars
Bars show cumulative requests per node; the small number is current in-flight load. Lower imbalance % means a more even spread.