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VMware Windows CPU hog

VMware Windows CPU hog applies stress on the CPU resources on Windows OS based VMware VM. It checks the performance of the application running on the VMware Windows VMs.

VMware Windows Cpu Hog

Use cases​

VMware Windows CPU hog:

  • Determines the resilience of an application when stress is applied on the CPU resources of a VMware Windows virtual machine.
  • Simulates the situation of lack of CPU for processes running on the application, which degrades their performance.
  • Helps verify metrics-based horizontal pod autoscaling as well as vertical autoscale, that is, demand based CPU addition.
  • Verifies the autopilot functionality of cloud managed clusters.

Prerequisites​

  • Kubernetes > 1.16 is required to execute this fault.

  • Execution plane should be connected to vCenter and host vCenter on port 443.

  • Adequate vCenter permissions should be provided to access the hosts and the VMs.

  • VMware tool should be installed on the target VM with remote execution enabled.

  • The VM should be in a healthy state before and after injecting chaos.

  • Kubernetes secret has to be created that has the Vcenter credentials in the CHAOS_NAMESPACE.

  • VM credentials can be passed as secrets or as a chaos engine environment variable.

apiVersion: v1
kind: Secret
metadata:
  name: vcenter-secret
  namespace: litmus
type: Opaque
stringData:
    VCENTERSERVER: XXXXXXXXXXX
    VCENTERUSER: XXXXXXXXXXXXX
    VCENTERPASS: XXXXXXXXXXXXX

Mandatory tunables​

Tunable Description Notes
VM_NAME Name of the target VM. For example, ubuntu-vm-1
VM_USER_NAME Username of the target VM. For example, vm-user.
VM_PASSWORD User password for the target VM. For example, 1234. Note: You can take the password from secret as well.

Optional tunables​

Tunable Description Notes
CPU_CORES Number of CPU cores subject to CPU stress. Default: 0. Indicates that all the avaialble CPU resources are consumed. For more information, go to CPU cores.
TOTAL_CHAOS_DURATION Duration that you specify, through which chaos is injected into the target resource (in seconds). Default: 60s. For more information, go to duration of the chaos.
RAMP_TIME Period to wait before and after injecting chaos (in seconds). For example, 30s. For more information, go to ramp time.
SEQUENCE Sequence of chaos execution for multiple instances. Default: parallel. Supports serial sequence as well. For more information, go to sequence of chaos execution.
DEFAULT_HEALTH_CHECKDetermines if you wish to run the default health check which is present inside the fault. Default: 'true'. For more information, go to default health check.

CPU cores​

The CPU_CORE environment variable applies stress on the target Windows VM for a specific duration. If the variable is set to 0, the fault consumes all the available CPU resources.

Use the following example to specify CPU cores:

# CPU hog in the VMware VM
apiVersion: litmuschaos.io/v1alpha1
kind: ChaosEngine
metadata:
  name: engine-nginx
spec:
  engineState: "active"
  chaosServiceAccount: litmus-admin
  experiments:
  - name: vmware-windows-cpu-hog
    spec:
      components:
        env:
        # Name of the VM
        - name: VM_NAME
          value: 'test-vm-01'
       # CPU cores for stress
        - name: CPU_CORES
          value: '1'