What is the impact of CPU high utilization in 4G Data experience?

Dear Experts.

What is the impact of CPU high utilization in 4G Data experience?

It means system is heavily loaded and may impact the performance of the node and in turn can result to service degradation.

Thanks. How to resolve this issue?

Good question. :slight_smile:

Check cell utilization / number of peak RRC connected users / high number of ping pong HO these are reason of high CPU utilisation in 4G.

You need to optimize cell level utilization_by traffic balancing / user balancing to reduce CPU utilization.

All cells have high CPU utilization.

It’s needed to look at different angle.

Be it application or at hardware could be a corner case for high CPU.

I faced this issue before, throughput was mainly affected.

The reason was from the high temperature.

Then it’s not cell specific issue.

Check if any new software package upgrade done recently on impacted nodes.

Normally vendors suggested threshold for CPU load of baseband or main control board, such as >=70% it should expand capacity.

But not clear it affect throughput.

Just in Call Admission flow, for example when CPU load very high >=95% eNB may restrict new users.

You can also check the RRC KPIs and rejection ratio during the high CPU load.

In my case: RRC users are high.–> RRC failure also increase due to shortage power → PRB decrease → Payload Decrease → Throughput decrease

Is there any KPI for CPU utilization in eNodeB?

LTE CPU utlilization is based on eNB Level.

Ok. Linked with base band utilization.

Not related to power shortage.

Its impacts all major LTE KPIs. Faced a similar issue and throughput, latency, ps dcr, erab sr was impacted. To resolve we performed below troubleshooting

  1. Added BPN card
  2. Balanced traffic on BPN card if multiple cards are configured
  3. Changed LTE into non-mixed if it was configured in mix mode.

Does Layer balancing within a site sector has positive effect on reducing CPU usage?
IF yes then how?