The device crashes when OpenThread uses the CONFIG_OPENTHREAD_NORDIC_LIBRARY_MASTER precompiled library.

[Quay]

Hi Nordicsemi engineers,

While testing a large-scale OpenThread network recently, I encountered an irregular pattern of device crashes. The network consists of 70 devices, all using the same pre-compiled firmware with `CONFIG_OPENTHREAD_NORDIC_LIBRARY_MASTER`. Typically, after more than 30 hours of operation, around three devices will crash.

SDK version: NCS3.0.0

SOC:NRF52840 QIAA

The network topology is as follows:

I believe the insufficient size of the message pool in the OpenThread precompiler settings caused a memory overflow, triggering the system crash.Because in my tests on another small network (5 devices), no device crashes occurred.

Our project targets over 150 devices. How should we proceed with the modification?

I'm really looking forward to your replies.

[Amanda Hsieh]

Hi Quay, 

The OpenThread samples in nRF Connect SDK use prebuilt OpenThread libraries where the maximum number of children is defined to be 32. If you want to change this, you need to build the libraries from source, as described in Select OpenThread libraries.

The 32 end nodes per router are the number we tested for our Thread certification. If you increase this number, you may have to modify the binaries, which may require extra work with Thread Certification. You cannot reference Nordic Component Certification to obtain a Product Certification if you build the libraries yourself. See Certification by inheritance with modifications to binaries for more information.

Regards,
Amanda H.

[Quay]

Hi Amanda,

I still don't understand, is the device crashing because the number of end nodes in the routing table exceeds 32?This crash behavior resembles triggering a fatal error and entering an assertion deadlock.No router was found to have more than 32 end nodes in the network topology diagram.

Regards,

Quay

[Amanda Hsieh]

Hi, 

Quay said:

No router was found to have more than 32 end nodes in the network topology diagram.

Got it. 

I believe the insufficient size of the message pool in the OpenThread precompiler settings caused a memory overflow, triggering the system crash.

It cannot adjust the size of the message pool for pre-compiled firmware. See the note in the Message pool configuration. If you want to change this, you need to build the libraries from source, as described in Select OpenThread libraries.

-Amanda H.