When I start load test then warning messages shows in EI log.
WARN - TargetHandler http-outgoing-519: Request not started while the handler is in an inconsistent state RESPONSE_DONE
WARN - SynapseCallbackReceiver Synapse received a response for the request with message Id : urn:uuid:38d9964b-4fec-4989-ae32-957f9636fa52 But a callback is not registered (anymore) to process this response
These warnings shows when call mediators call backend.
That can't be timeout becouse fault sequnece is no called.
Single invocation does not generate these warnings. Warnings only appear under load test.
How can I do to solve these warnings?
EDIT:
I log message:
2020-12-17 12:06:35,671 - call backend
2020-12-17 12:06:35,681 - warn
2020-12-17 12:06:35,706 - response from backend
after warnings, message is further processed correctly
The explanation for the below WARN message.
In the WSO2 EI, the requests are handled through the PassThrough Transport in an asynchronous manner. Let's say the EI server received a request. Then a single thread is used to serve the request and perform the mediation. Before the request is sent to the external back end, a callback is registered in the callback store and the thread is released to the thread pool. When the response is received for the particular request, another thread is used to correlate the callback and handle the response. the call back is cleared from the callback store if the response is received or after the endpoint timeout.
If the response is received after time out(due to the slowness of the back end), above WARN message is logged since the callback is not available in the callback store.
I assume that your back end is getting slower with the load. You can check this by directly hitting a load on the back end service.
It seems that the other WARN message is logged due to an inconsistency of the sate machine in EI[1]. If you can, share the complete synapse configs related to flow.
[1] https://wso2.com/library/articles/2014/04/demystifying-wso2-esb-pass-through-transport-part-iii