Splendid The log covers app. 9h of time, that should give us an idea of what is happening.
I’ve uploaded the log into the Z-Wave Log Viewer that Chris provides on his website.
Looking at the Filter option I count only 27 nodes that take part in the communication. Your network map shows way more than these 27 nodes. Also in the network map I see #76 as the node with the highest number, but in the filter view of the log viewer there is a node #255. Filtering for this node does not give any hints, maybe this is just data garbage that cannot be associated with a single node.
Filtering randomly for one node, #61, shows some traffic. Temperature is reported, but it seems that you took care to avoid traffic: only changes of at least 0,5 degF are reported, or multiples of that. That’s good, avoiding unnecessary traffic is one of the top priorities in a network with limited bandwith but a lot of participating communication partners.
And to the next random node, #28. Only ONE message is shown. Either it is a node that has not much to report or it has no chance to do so. I cannot tell.
Node #8 is similar, only 2 points in time it is seen in the logs.
On to node #75. Now it gets interesting. There are several messages “DeleteSUCReturnRoute”. Is there more than one controller in your setup? What are the settings for your controller(s)?
Node #48: Only one point in time this node communicates. But it is shown that it took over 20 seconds to receive an acknoledgement from the device. Only 3 other nodes were communicating at 16:41:xx. That does not look like congestion of the network.
Node #55: Between 7:54 and 9:39 the node does not report anything, there are messages containing “DeleteSUC ReturnRoute”. But at 16:22 it starts reporting kWh, beginning every two minutes, then it becomes more erratic.
I cannot pinpoint something (to me) obvious. But I’m curious why a lot of nodes shown in your network view are not seen in the logfile.
Looking at the file without the logviewer at Chris’s website I see messages like
2020-12-27 08:04:32.099 [DEBUG] [ng.zwave.internal.protocol.ZWaveNode] - NODE 23: SECURITY not supported
2020-12-27 08:04:32.099 [DEBUG] [ng.zwave.internal.protocol.ZWaveNode] - NODE 23: Command Class COMMAND_CLASS_SWITCH_MULTILEVEL is NOT required to be secured
2020-12-27 08:04:32.102 [DEBUG] [ng.zwave.internal.protocol.ZWaveNode] - NODE 29: SECURITY not supported
Are your devices included with security enabled? That puts a strain on all the processing, in the devices as well as on the controller. Maybe that is a hint.
Did you check the load on the system where OH is running?