Gateway Hangs

[RexBelli]

I'm seeing an issue where the gateway hangs after some amount of time. I've seen it last multiple weeks, or just 10 minutes. When it's hanging, there's no output to stdout/stderr. This is the strace output when it goes into the hung state:

gettimeofday({tv_sec=1578760744, tv_usec=315033}, NULL) = 0
gettimeofday({tv_sec=1578760744, tv_usec=315577}, NULL) = 0
gettimeofday({tv_sec=1578760744, tv_usec=316024}, NULL) = 0
stat64("/etc/localtime", {st_mode=S_IFREG|0644, st_size=3687, ...}) = 0
write(2, "Jan 11 16:39:04 \33[36mDEBUG\33[0m ", 31) = 31
write(2, "TSF:MSG:READ,2-2-0,s=10,c=1,t=0,"..., 52) = 52
getsockopt(5, SOL_TCP, TCP_INFO, "\10\4\6\0\6\7g\0\0$\364\0@\234\0\0\200\5\0\0\30\2\0\0\1\0\0\0\0\0\0\0"..., [104]) = 0
ioctl(5, FIONREAD, [0])        = 0
ioctl(5, TIOCOUTQ, [1988])     = 0
nanosleep({tv_sec=0, tv_nsec=1000000}, NULL) = 0
ioctl(5, TIOCOUTQ, [1988])     = 0
nanosleep({tv_sec=0, tv_nsec=1000000}, NULL) = 0
ioctl(5, TIOCOUTQ, [1988])     = 0

The last two lines repeat forever, or at least as long as I've waited, multiple days in some cases. I have the rest of the output if it's helpful.

Hardware: Raspberry Pi Zero W (Raspbian 10) with rfm69hw Software: I've tried the dev branch and 2.3.2 release. Both configured with:

MY_RFM69_NETWORKID=5 \
	./configure \
	--my-transport=rfm69 \
	--my-rfm69-frequency=915 \
	--my-is-rfm69hw \
	--extra-cxxflags="-DMY_RFM69_NETWORKID=\(28\)" \
	--my-rfm69-encryption-enabled \
	--my-gateway=mqtt \
	--my-controller-url-address=<redacted> \
	--my-mqtt-publish-topic-prefix=harper-out \
	--my-mqtt-subscribe-topic-prefix=harper-in \
	--my-mqtt-client-id=gw-harper \
	--my-mqtt-user=gw-harper \
	--my-mqtt-password=<redacted> \