Description of problem:

Durning CUDN BGP export scenario scale testing,

• High cpu usage of ovnkube-controller container 
• High cpu usage on both master and worker nodes

I am scale testing BGP router export scenario on a OCP 4.19 baremetal cluster with 24 worker nodes (no infra nodes) using 4.19.0-ec.3 with  OVNK BGP image which is built using the PR  build 4.19,openshift/ovn-kubernetes#2239 on 03/25/2025.

Test creates 72 CUDN, 1 namespace per CUDN and 1 pod per namespace. I waited for 30 minutes after creating all the resources and before creating router advertisements.

Then test creates 72 router advertisements where each RA advertises only one unique cudn i.e RA:CUDN is 1:1.

Average CPU usage of "controller" container (in frr-k8s pod of openshift-frr-k8s namespace) is 1390% and max cpu usage is 1813%.

We see very high cpu usage on each master node as well i.e avg 2935% and max 4625%.

cpu usage on each worker node avg 2835% and max 4472%

Test results are avaialble at https://docs.google.com/spreadsheets/d/1WLuTpcrTwFBUcZ-XF2wppOJL9M13_V_HYh2i23UpQUo/edit?usp=sharing 
Grafana screenshots at https://storage.scalelab.redhat.com/anilvenkata/bgp/ra72export/ 

I can provide the live environment to the engineer for troubleshooting.