1

I'm trying to build a cost model for my distributed system where Event Grid is a key piece.

Event Grid cost is based on millions of operations (0.561€ per million). See documentation.

This is the cost of my Event Grid on one production environment for one month: Event Grid actual cost

These are the metrics for the same month: enter image description here

Published Events + Delivered Events = 67.93M

67.93M * 0.561€ = 38.10€

This is ~3.5 less times than the actual cost. I have run same exercise on other environments with less workload and the result is pretty similar, between 3 and 4 times less than the actual cost.

Does anyone know what am I missing to estimate correctly the cost of my Event Grid instance?

DavidGSola
  • 697
  • 5
  • 17

1 Answers1

0

Assuming that the number you have is the actual number of events.

Then there maybe 3 (at least) reasons that you are being billed for more:

  • Are the events being delivered to multiple endpoints. You pay per delivery.
  • Have some of your systems had an outage? You pay for retry events.
  • Are your events larger than 64KB. For each message you pay per 64KB increment.

See: https://azure.microsoft.com/en-us/pricing/details/event-grid/?cdn=disable

Shiraz Bhaiji
  • 64,065
  • 34
  • 143
  • 252
  • - Yes, most of the events are sent to at least 3 endpoints. But I guess that's already taken into the consideration on the metrics since the `Delivered` are almost three times the `Published`. So `Deliveries` are being taken into consideration on this cost calculations. - Some services might have a low outage but not that high to increase the cost 3 times. - No, I apply claim-check pattern so every event is lower than 64KB. – DavidGSola Jun 16 '23 at 08:49
  • How is your filtering set up can an event be checked against several filters before it is matched? – Shiraz Bhaiji Jun 16 '23 at 09:33
  • No advanced filtering, just filtering by the subject `suffix`. Btw, I'm using Cloud Event Schema, but I don't think it affects. – DavidGSola Jun 16 '23 at 10:32