Crio CPU usage jumping between 35% to 50% periodically

[IYED]

Hi gents,

I have a Crio 9024, in my RT application, I have 2 processing loops, the first one run each 200 ms and the second one is a dynamic event loop running each 3s. So the CPU usage jumps from 35% to 50% each 3s to process the event is't normal ??? this kind of app can be harmful for crio'CPU or not ?

Thanks 

[chembo]

I think the recommendation is keep the CPU load lower that 75%-80%, so you should be fine.

[altenbach]

What happens inside that event?

Why do you think that a slight rise in CPU usage would be harmful?

[IYED]

Thanks gents for your fast reply,I was thinking it could be harmful because it's periodically jumping. so I'm just asking to know if it's normal or not.

[GerdW · Accepted solution]

It jumps periodically as you call some routines periodically…

Why do you think it's not normal?

[IYED]

Thanks

[altenbach · Accepted solution]

Your program is doing something extra every 3 seconds and CPU usage raises briefly every 3 seconds.

Coincidence? I don't think so! 😄

[chembo · Accepted solution]

This is a very good source of information about cRIO http://www.ni.com/pdf/products/us/fullcriodevguide.pdf

I was a little bit high with 80%. See page 46:

When designing your real-time target application, you should aim for a CPU usage below 70 percent. You can monitor CPU usage with the NI Distributed System Manager or programmatically with the RT Get CPU Loads VI. Consider the following when trying to reduce the CPU usage of your application.