Config Rollout Time Calculator

Work out config rollout time instantly with clear inputs, formula shown and shareable results.

About Config Rollout Time Calculator

Rolling a configuration change trades speed against blast radius. Small batches limit how many nodes a bad change can break at once but multiply the number of bake intervals, so 800 nodes in batches of 40 takes 20 batches and nearly an hour. The right batch size is the largest whose failure you could absorb, not the largest the tooling allows.

Formula

Rolling update

batches = ceil(nodes / batch size); total = batches x per-batch time + (batches - 1) x bake time; blast radius = batch size / nodes

Worked example

With the default values below, Config Rollout Time Calculator returns Total rollout time of 2,940. Change any input above and every figure here is recalculated in your browser.

Inputs used

Nodes to updateminimum 1: 800
Nodes per batchminimum 1: 40
Time per batch including verificationminimum 0.1 s: 90 s
Bake time between batchesminimum 0 s: 60 s

Results

Total rollout time: 2,940 s
Batches: 20
Rollout time in minutes: 49.0 min
Maximum blast radius per batch: 5.00%

Step by step

1Values used
2Rolling update
3Total rollout time= 2,940 s
4Batches= 20
5Rollout time in minutes= 49.0 min
6Maximum blast radius per batch= 5.00

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Should batch size grow through the rollout?

Yes, that is the exponential pattern: start with one node, then a small percentage, then larger batches once confidence is established. It gives both safety and speed.

What should the bake time verify?

Error rate and latency on the updated nodes specifically, compared against the un-updated ones. Comparing against the global average hides a problem affecting only the new batch.