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Bug
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Resolution: Duplicate
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Major
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None
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4.14
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No
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Rejected
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False
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Description of problem:
We are running a test that has two distinct phases - a creation/ramp-up phase that creates a lot of resources like pods, services, network policies, namespaces etc and then a churn phase that deletes and recreates 10% of all resources created for about an hour to mimic a cluster in steady state. We notice that ovnkube-node container on the worker nodes is very spiky during the deletion phase as compared to the create phase in OVN-IC. We see a lot more CPU usage during the deletion actions as part of the "churn" phase when compared to the creation actions in the ramp-up phase.
Version-Release number of selected component (if applicable):
4.14.0-0.nightly-2023-08-08-094653
How reproducible:
100%
Steps to Reproduce:
1. Use kube-burner to run this workload on a ROSA/Self-managed OCP cluster 2. https://github.com/smalleni/kube-burner/commit/d2b4f20f1de20ca0e70d71070331ae61e15698a0 3. kube-burner ocp cluster-density-v2 --iterations=650
You can also reproduce this by running the regular clcuster-density-v2 workload with churn=true
Actual results:
High CPU usage during the churn (resource deletion/re-creation) phase
Expected results:
CPU usage should be lower
Additional info:
The biggest difference in CPU usage when comparing the ovnkube-node pod seems to be coming from the CPU usage of the ovnkube-node container during creation and deletion. The other containers are not contributing much to the difference.
ovnkube-node container CPU usage during creation phase: https://grafana.rdu2.scalelab.redhat.com:3000/dashboard/snapshot/FemcDupRa7aKUZMWqfu9xSGoOK7HwmxT
ovnkube-node container CPU usage during delete/recreate operation: https://grafana.rdu2.scalelab.redhat.com:3000/dashboard/snapshot/VxNUFvyPQYvSgnQSaGbncHs3yJmpkX0Y