Weighted Load Distribution Calculator
Turn pool member weights into request shares, per-pool request counts and the weighted round-robin cycle length.
Inputs
Weighted Round-Robin Cycle Length
10requests
Share to Member A
50.00%
Share to Member B
30.00%
Share to Member C
20.00%
Requests to Member A
30,000
Requests to Member B
18,000
Requests to Member C
12,000
Step by step
Values used
Weight of pool member A = 5; Weight of pool member B = 3; Weight of pool member C = 2; Requests to distribute = 60,000 requests
Weighted Load Distribution
share of member i = weight_i ÷ Σ weights; requests to member i = total requests × share; the WRR cycle repeats every Σ weights requests.
Weighted Round-Robin Cycle Length
= 10 requests
Share to Member A
= 50.00
Share to Member B
= 30.00
Share to Member C
= 20.00
Requests to Member A
= 30,000
Requests to Member B
= 18,000
How it works
Weighted round robin hands out one request per unit of weight, so a member with weight 5 in a pool summing to 10 receives half the traffic. The pattern repeats once the sum of the weights has been dispensed, which is why the cycle length matters for short bursts. Weights are how you mix server generations in one pool or ramp a canary, but the cycle length means a burst shorter than the sum of the weights will not honour the ratio at all.
Formula
Weighted Load Distribution
share of member i = weight_i ÷ Σ weights; requests to member i = total requests × share; the WRR cycle repeats every Σ weights requests.
- Σ weights
- Sum of all pool member weights, which is also the cycle length
- share
- Long-run proportion of requests a member receives
Frequently Asked Questions
How is Weighted Load Distribution calculated?
share of member i = weight_i ÷ Σ weights; requests to member i = total requests × share; the WRR cycle repeats every Σ weights requests. Weighted round robin hands out one request per unit of weight, so a member with weight 5 in a pool summing to 10 receives half the traffic. The pattern repeats once the sum of the weights has been dispensed, which is why the cycle length matters for short bursts.
Why does Weighted Load Distribution matter?
Weights are how you mix server generations in one pool or ramp a canary, but the cycle length means a burst shorter than the sum of the weights will not honour the ratio at all.
What values do I need to enter?
This calculator takes 4 inputs: Weight of pool member A, Weight of pool member B, Weight of pool member C, Requests to distribute. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.
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