Round Robin Distribution Calculator

Show exactly how round-robin splits requests across a pool, including the remainder servers and the resulting per-server load.

Inputs

Requests in the measurement windowrequests

Servers in the poolservers

Request rate at peakrps

Capacity per serverrps

Requests per Server

14,285

Servers Taking One Extra Request

Peak Load per Server

2,000.0rps

Server Utilisation at Peak

80.0%

Distribution Imbalance

0.007%

Utilisation After Losing One Server

93.3%

Step by step

Values used
Requests in the measurement window = 100,000 requests; Servers in the pool = 7 servers; Request rate at peak = 14,000 rps; Capacity per server = 2,500 rps
Round Robin Distribution
requests per server = floor(requests ÷ servers); the first (requests mod servers) servers take one extra request; per-server rate = request rate ÷ servers.
Requests per Server
= 14,285
Servers Taking One Extra Request
= 5
Peak Load per Server
= 2,000.0 rps
Server Utilisation at Peak
= 80.0
Distribution Imbalance
= 0.007
Utilisation After Losing One Server
= 93.3

How it works

Round robin walks the pool in order, so each server receives the integer quotient of the request count and the first few servers absorb the remainder. Because the split ignores server capability, the per-server rate is simply the total divided by the pool size. Round robin only balances load when every server is identical and every request costs the same — the failover column is the one that decides whether the pool survives a node loss.

Formula

Round Robin Distribution

requests per server = floor(requests ÷ servers); the first (requests mod servers) servers take one extra request; per-server rate = request rate ÷ servers.

serversWithExtra: requests mod servers — the remainder of the division
failoverUtilisation: Load per server once the pool is one member short

Frequently Asked Questions

How is Round Robin Distribution calculated?

requests per server = floor(requests ÷ servers); the first (requests mod servers) servers take one extra request; per-server rate = request rate ÷ servers. Round robin walks the pool in order, so each server receives the integer quotient of the request count and the first few servers absorb the remainder. Because the split ignores server capability, the per-server rate is simply the total divided by the pool size.

Why does Round Robin Distribution matter?

Round robin only balances load when every server is identical and every request costs the same — the failover column is the one that decides whether the pool survives a node loss.

What values do I need to enter?

This calculator takes 4 inputs: Requests in the measurement window, Servers in the pool, Request rate at peak, Capacity per server. 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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