cRIO CPU usage high - i801 SMBus interrupt

[Corey.Rotunno]

Hi, 

  I have been running into high CPU usage on a cRIO-9048. Even with no RT VI's running, I am often in the 30's of percents. I have done a little digging, it seems that the i801 SMBus is firing lots of interrupts. This interrupt is consistently consuming 20-25%, sometimes even more. 

Does anyone know what this is for? I am considering disabling interrupts for this per instructions linked below. However, I would really love to know what it's doing before I go and disable interrupts. 

EDIT : I did have an NI9870 and NI9871 (serial interfaces) configured to use "Real-Time Scan" so they appear as regular COM ports. I switched this back to "LabVIEW FPGA" thinking that maybe this was the source of the interrupts. It is not 😞

Thanks,
Corey

[Corey.Rotunno]

Duplicate thread. Sorry :/. Posted here first and it was auto-removed. Then posted in the hardware section. Then moderator un-removed this post. 


Annnnnyhow, hardware thread is here if anyone is interested in knowing more or could possible help. https://forums.ni.com/t5/Real-Time-Measurement-and/cRIO-CPU-usage-high-i801-SMBus-interrupt/m-p/4358...