On a fresh cluster deployment, applying performanceprofile or kubeletconfig for the first time (no reserved memory-related changes were done previously) with systemReserved changes causes ALL cluster nodes to reboot, event nodes this change is unrelated to.

Important: 
 - nodes for which the change is not relevant for, were just rebooted, and the change was not applied for them

- such all nodes reboot only once on the clean deployment; on the following changes for the system, reserved memory/CPU by performanceprofile or kubeleteconfig were rebooted relevant nodes only

Client Version: 4.15.0-ec.3
Kustomize Version: v5.0.4-0.20230601165947-6ce0bf390ce3
Server Version: 4.15.0-ec.3
Kubernetes Version: v1.28.3+20a5764

the same issue observed on 4.14 as well:
Client Version: 4.14.6
Kustomize Version: v5.0.1
Server Version: 4.14.6
Kubernetes Version: v1.27.8+4fab27b 

    always

    1. deploy cluster (even the minimal cluster will be suitable to reproduce this issue: 3 masters + 2 workers
    2. apply kubeletconfig related to the reserved memory change. For example:

apiVersion: machineconfiguration.openshift.io/v1
kind: KubeletConfig
metadata:
  name: set-sysreserved-master
  resourceVersion: "774812"
  uid: 3a575d56-d5ac-4e12-bbdf-5f7c328ed705
spec:
  kubeletConfig:
    systemReserved:
      cpu: 500m
      memory: 27Gi
  machineConfigPoolSelector:
    matchLabels:
      pools.operator.machineconfiguration.openshift.io/master: ""


    

kubeletconfig was created, change was applied to all master nodes, and master nodes were rebooted. But simultaneously, a rolling reboot of the worker nodes was started.

    kubeletconfig was created, change was applied to all master nodes, and master nodes were rebooted. And no workers reboot should be observed

    performanceprofile example:

apiVersion: performance.openshift.io/v2
kind: PerformanceProfile
metadata:
  name: performance-samsung-cnf
spec:
  additionalKernelArgs:
  - mmio_stale_data=off
  - mds=off
  - tsx_async_abort=off
  - retbleed=off
  cpu:
    isolated: 2-19,22-39,42-59,62-79
    reserved: 0-1,20-21,40-41,60-61
  globallyDisableIrqLoadBalancing: false
  hugepages:
    defaultHugepagesSize: 2M
    pages:
    - count: 32768
      node: 0
      size: 2M
    - count: 32768
      node: 1
      size: 2M
  machineConfigPoolSelector:
    machineconfiguration.openshift.io/role: samsung-cnf
  nodeSelector:
    node-role.kubernetes.io/samsung-cnf: ""
  numa:
    topologyPolicy: single-numa-node
  realTimeKernel:
    enabled: false
  workloadHints:
    highPowerConsumption: false
    realTime: false