4 backends with random service times. Watch distribution and queue depths.

What you're seeing

Round-robin: simple, ignores backend load. Least connections: routes to least busy. Random: stateless, statistically OK. Weighted: respects backend capacity.

Real load balancers (Envoy, HAProxy, NLB) often combine algorithms with health checks. Least-conn with EWMA latency is the modern default.

★ KEY TAKEAWAY
Round-robin: simple, blind. Least-conn: smart, slow under spikes. Random: stateless, decent. Weighted: respects backend capacity.
▶ WHAT TO TRY
  • Click Burst 30 requests.
  • Switch algorithms — see which keeps backends balanced.
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