Azure Event Grid Egress Limit

Question

For our project we want to understand the Egress limits for sending events to configured subscribers in an Azure Event Grid. Looking at the documentation https://docs.microsoft.com/en-us/azure/azure-resource-manager/management/azure-subscription-service-limits it is not clear as to what is the egress limits in Event Grid ?

What is the difference between:

Publish rate for a custom topic (ingress) of 5,000 events per second per topic

And

Publish requests of 250 per second ?

Thanks

Veikko Veikko · Accepted Answer · 2020-02-26T18:52:53

There is no documented hard limits for EventGrid egress. Quotes from some Microsoft documents:

High throughput - Build high-volume workloads on Event Grid with support for millions of events per second. (from https://docs.microsoft.com/en-us/azure/event-grid/overview#capabilities)

and

Scalability: High: Capable of routing 10,000,000 events per second per region. (from https://docs.microsoft.com/en-us/azure/iot-hub/iot-hub-event-grid-routing-comparison)

If EventGrid scales well over 10M events/s/region, the first practical checkpoint and possible limit would be money: you would run out of free quota (100k events) in 0.01 seconds and after that it would cost you $6/second to handle 10M events/sec. This is a run rate of $6/sec = $360/min = $21.600/hour = $518.4k/day = $15.552.000/month. I personally would be hitting my credit card limit in an hour.

Your second questions about request limits and event limits is easier to answer. Request limit is for publish requests and event limit is for number of events in these requests. You can and should publish events in batches to not hit the 250 publish requests limit. You can batch 1-5000 events in one publish request. More info on batching can be found here:

EventGrid egress is not normally a limiting constraint with EventGrid. I hope this helps you architect your solution.

Azure Event Grid Egress Limit

1 Answers