Vantage · tool

Flow spool calculator

How fast a sensor’s local spool grows per second of traffic, and how many hours of collector outage a given cap absorbs. Everything is computed in your browser: nothing you type here leaves your machine.

Parameters — flow rate

220 B is what one record takes as uncompressed JSON, exactly as the sensor writes it to the spool.

Move this to see what share of the cap an outage that long would take.

Growth
1,58GB/h
Per day
38,0GB/day
Time to fill the cap
25,3h
Coverage
1,1days of outage

Spool usage at the simulated outage HEALTHY

0 GB0 %40 GB

Reference scenarios

ScenarioNew flowsGB/hCoverage with 40 GB

These are not measurements of any deployment: they are stated assumptions — 800 B packets, 20 packets per flow, 220 B per record — computed with the same formulas as this page. Press "use" to load one into flow-rate mode and adjust it.

The maths is simple and in plain sight: bytes per second = flows per second × bytes per record. What it does not model is compression at rest, nor how fast the collector drains the spool once it returns — which is why it gives the pessimistic case, the one worth sizing against.