Influxdb, Grafana causing system overload?

I just recently installed Influxdb with Grafana on a Raspberry Pi4. I’ve madeone HABpanel with an embedded link to a Grafana graph. When I access this HABpanel on my mobile the Pi seems to get overloaded.
I have the following setup:
A Pi4 acting as VPN server running Wiregurad and Pihole.
One Pi4 as Openhab server connected as client to the VPN located in the Netherlands,
Another Pi4 located in Italy also connected as a client to the VPN server thru a mobile 4G modem. (remote location no wired Ethernet available). Problem occurs on this Pi that I cannot access physically due to the distance.

After having viewed the HABpanel on my mobile phone, connection to the PI is lost. I can still ping it but on every attempt to connect to it I get a timeout message, even SSH terminal access is not possible anymore.

I am, thru a secondary system, able to cut power to the Pi so it reboots again (I’ve build this in as a safety backup for problems like this).

After the system has rebooted I can see nothing strange in the normal log files. What I do see is that the Openhab instance has been running until the moment I cut power, the events.log file has entries up the moment of the reboot.

Are there any tools I can use to monitor the system load during the viewing of the HABpanel? Or other ways to analyse what’s going on? I am new to both Openhab and RPi’s and on a steep learning curve.

Will

There are different tools that you can use. One of them is top to see the CPU load, memory usage, load caused by different processes.
For a comparison of different tools you may have a look at https://www.linux-magazine.com/Issues/2014/167/Real-Time-Monitoring-Tools

You can run the top command and it updates the output itself overtime.
You also can run it in an ‘endless’ loop and write statistics from header to a file ( make sure that it is not stored in an area that will be deleted after a reboot ).

while [ 1 ]; do top -n 1 -b | head -5; echo; sleep 60; done | tee -a /home/MyUser/top.log

@Wolfgang_S Thanks for the link and info on the tools, will try to grasp the load info to figure out what’s going on.

Regards Will