modbus polling and cpu overcharging

[gdimaria]

hi,
I have a LM whose CPU is often overloaded (it even restarts!).
I have analyzed every possible cause, including infinite loop scripts, but nothing. 
The only thing I notice is a continuous telegram traffic from an external modbus gateway to which several devices are connected. 
There are several telegrams frequently updated and/or repeated. 
Could this be the cause of the overload?
Is it possible to monitor the CPU load trend to determine when it overloads?

Thanks in advance

Peppe

[admin]

Install System load app and check which process is consuming max CPU/RAM.

[gdimaria]

Install System load app and check which process is consuming max CPU/RAM.

I already done, those ones are always in pole position... enspecially nginx (there are several users simultaneously pointing their browser to LM).