WAAS experiencing high CPU utilization

[deshaw]

We are monitoring WAAS devices for CPU utilization in our Network.Currently we have set the threshold for 70%. At this threshold we see a large number of alerts from WAAS crossing 70% CPU utilization. I guess 70% CPU utilization is normal for WAAS. Am I right???

[Daniel Arrondo Ostiz]

Hi,

Whether it's normal or not would depend on how much traffic it's processing.

I would suggest you to check some historical graphs of the CPU usage. If you see it goes up to 70% during peak hours but goes down when the network is not used so much, then, this value is probably normal for your setup.

Regards

Daniel

[deshaw]

Hi Daniel,

Yes, during the peak hours sometimes the CPU shoots even upto 95% and then in next 5 min comes down to normal below 70%.

Since our threshold is 70%, we get a lot of inactionable(because it becomes normal in 5-10 miinutes only) alert.I was wondering if we could change the threshold.

One of the Cisco Tac Engineer replied to the above question :

That is true. It is normal to have a high CPU utilization in normal Operation as we mentioned earlier it runs on underlying Linux kernel and linux does not use Page file rather it uses Maximum RAM that it could .

Regards,

Mohit

[Daniel Arrondo Ostiz]

Hi,

I'm afraid it's not possible to change the thresholds. 70% was hard coded as it's considered a good threshold for overload. If you frequentlyt have values above that, then, you should consider either replacing this device with a more powerful one or load-balance the traffic between several WAE.

Regarding your second comment. The statement applies to memory usage only (where it's normal to have it at 95%), but not for CPU.

Regards

Daniel

[deshaw]

Thanks Daniel