Coap Communication leads to memory leak

[Pritesh-1011]

Hi OpenThread community!

I am using the coap communication as the protocol for the data exchange between the devices with the confirmation flag enable. So when I send the data from the Gateway to Endnode, Endnode will send the confirmation to gateway but it leads to some memory leak during the session. And If remove the confirmation flag then there is no memory leak.

Attached the logs file for the Gateway and Endnode for the reference.
Note : Used Openthread version 1.2
EndNode.txt
Gateway.txt
.

[jwhui]

It appears that your child is configured as a sleepy end device. If so, what is the poll period value? See pollperiod CLI command.

Note that poll period will determine the latency sending messages (in this case the CoAP ACK message) to the sleepy end device.

[Pritesh-1011]

Hello jwhui,

Thank you so much for the reply.
Here the demo code that I am using is for the sleepy end devices. But the devices will only move into sleep mode when I pressed the button otherwise it will work as the active device.

So when I was facing the issue, my device was not in sleep mode. so Coap ACK messages will be sent instantly.

[jwhui]

OK, then what you are observing are the cached responses - see my other answer #7866 (comment).

[jwhui]

What you are observing are the cached responses to support message de-duplication - see:

openthread/src/core/coap/coap.hpp

Line 276 in b71c159

class ResponsesQueue