Serf process not responsive anymore

Hi,

I'm observing this strange error for some time and it seems to only reveal itself after running for around 14 days.
We are running this on our armv5te boards.
Using the discover option and also using encryption.
Serf versio = 0.6.3

I finally managed to get a trace from serf after it became unresponsive by:
killall -SIGABRT serf
I attached the output.

Any help is appreciated!!

Thanks in advance
Jaap

[trace.txt](https://github.com/hashicorp/serf/files/66572/trace.txt)