kubevirt: kubevirt it takes too long to start the window vm

What happened: kubevirt it takes too long to start the window vm( spent at least 4 minutes)

What you expected to happen: How to optimize to reduce startup time?

How to reproduce it (as minimally and precisely as possible): windows.yaml:

apiVersion: kubevirt.io/v1alpha3
kind: VirtualMachineInstance
metadata:
  labels:
    special: vmi-windows
  name: vmi-windows
spec:
  domain:
    clock:
      timer:
        hpet:
          present: false
        hyperv: {}
        pit:
          tickPolicy: delay
        rtc:
          tickPolicy: catchup
      utc: {}
    cpu:
      cores: 2
    devices:
      disks:
      - disk:
          bus: virtio
        name: cloudinitdisk
      interfaces:
      - bridge: {}
        model: e1000
        name: default
    features:
      acpi: {}
      apic: {}
      hyperv:
        relaxed: {}
        spinlocks:
          spinlocks: 8191
        vapic: {}
    firmware:
      uuid: 5d307ca9-b3ef-428c-8861-06e72d69f223
    machine:
      type: q35
    resources:
      requests:
        memory: 2Gi
  networks:
  - name: default
    pod: {}
  terminationGracePeriodSeconds: 0
  volumes:
  - name: cloudinitdisk
    containerDisk:
      image: www.myregistry.com:5000/kube-win7:latest

kubectl create -f windows.yaml
#It takes 4 minutes to start

Environment:

• KubeVirt version v0.17.0
• Kubernetes version v1.13.5

Thanks in advance.