Axon Server Buffer is full Error

We are using shared Axon Server with free version in our non-prod environment. We had encountered the following error on 18th Jan;

org.axonframework.axonserver.connector.AxonServerException: Buffer is full, slow down.
	at org.axonframework.axonserver.connector.ErrorCode.lambda$static$26( ~[axon-server-connector-4.6.1.jar:4.6.1]

Could you please help me to understand what’s this Error is about, throughput limit etc for free version?

Indeed, its throughput limit for the free version (Axon Cloud), all contexts on shared SaaS have this limitation. Limit allows you to hold 1000 commands and 1000 queries in the internal cache, meaning, you can have 1000 commands and 1000 queries running at the same time. Unless you are having really really high throughput, problem might be that your message handlers are too slow, and they don’t get executed in time, which fills in this buffer.

(My previous response due to misinformation that you are using Axon Server EE , that’s why its deleted.)

Thank you Stefan. What are the limits of Axon Server EE for no of commands and queries?

For Axon Server EE this is configurable, but by default, there is no hard limit set and it all depends on how much resources you assign to the instance (memory)


Thanks @stefand for your detailed response. Is there anything we can do to clear the cache? we are not able to use the context once it reaches limit even though we are not sending many messages.

We will clear the cache today and check if anything other then client application is causing the problem. In future feel free to report any issues to

Hi Arunkumar,
can you please give me the context name? are you still able to reproduce the issue?


Thanks for your response and recommendations. It is working smoothly as of today. I will contact support when we hit the limit again.