Why is eventRecordQPS defaulted to 5?

[zbialik]

Environment:

• Cloud provider or hardware configuration: on-prem

• OS (printf "$(uname -srm)\n$(cat /etc/os-release)\n"):

  Linux 5.4.0-53-generic x86_64
  NAME="Ubuntu"
  VERSION="20.04 LTS (Focal Fossa)"
  ID=ubuntu
  ID_LIKE=debian
  PRETTY_NAME="Ubuntu 20.04 LTS"
  VERSION_ID="20.04"
  HOME_URL="https://www.ubuntu.com/"
  SUPPORT_URL="https://help.ubuntu.com/"
  BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
  PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
  VERSION_CODENAME=focal
  UBUNTU_CODENAME=focal
  

• Version of Ansible (ansible --version): ansible-core==2.12.5

• Version of Python (python --version): 3.9

Kubespray version (commit) (git rev-parse --short HEAD): 2cf23e310

Network plugin used: cilium

Full inventory with variables (ansible -i inventory/sample/inventory.ini all -m debug -a "var=hostvars[inventory_hostname]"):

[all]

[kube_control_plane]
kubm04 node_labels='{"nodegroup.io/name": "core"}'
kubm05 node_labels='{"nodegroup.io/name": "core"}'
kubm06 node_labels='{"nodegroup.io/name": "core"}'

[etcd]
kubm04 etcd_member_name=etcd1 node_labels='{"nodegroup.io/name": "core"}'
kubm05 etcd_member_name=etcd2 node_labels='{"nodegroup.io/name": "core"}'
kubm06 etcd_member_name=etcd3 node_labels='{"nodegroup.io/name": "core"}'

[calico_rr]

[k8s_cluster:children]
kube_control_plane
kube_node
calico_rr

########################
# worker nodes section #
########################
[kube_node:children]
devops

[devops]
kubw01 node_labels='{"node-role.kubernetes.io/node": "", "nodegroup.io/name": "core"}' node_taints='["nodegroup.io/dedicated=core:NoSchedule"]' system_cpu_reserved="1000m" system_memory_reserved="2Gi"
kubw02 node_labels='{"node-role.kubernetes.io/node": "", "nodegroup.io/name": "core"}' node_taints='["nodegroup.io/dedicated=core:NoSchedule"]' system_cpu_reserved="1000m" system_memory_reserved="2Gi"
kubw03 node_labels='{"node-role.kubernetes.io/node": "", "nodegroup.io/name": "core"}' node_taints='["nodegroup.io/dedicated=core:NoSchedule"]' system_cpu_reserved="1000m" system_memory_reserved="2Gi"

[all:vars]
kube_network_plugin=cilium
kube_version=v1.24.6
kubelet_config_extra_args={"evictionHard": {"memory.available": "500Mi", "nodefs.available": "5Gi"}}
no_kube_reserved=True

Command used to invoke ansible: /venv/bin/ansible-playbook --become -i inventory/mycluster.ini cluster.yml

Output of ansible run:

Anything else do we need to know:

I see the default eventRecordQPS set in kubelet configs to be 5, but kubernetes has this defaulted to 50 (see docs).

My question is why does kubespray set the eventRecordQPS to 5? Shouldn't we just not define it in the kubelet config and let kubernetes decide what the default should be (based on the version ran)?