I do not know if this is specific to GKE or k8s storage in general. I assume it’s user error.

I’m creating PVCs in GKE with both requests and limits set (to the same thing) but the resulting PV capacity is much higher, as well as the capacity shown in PVC status. For example, a request for 1Gi resulting in 2.5Ti. I don’t know where the 2560Gi is coming from after searching around the GKE console:

Original request for a 1G PVC:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc0
spec:
  accessModes:
  - ReadWriteMany
  resources:
    limits:
      storage: 1Gi
    requests:
      storage: 1Gi
  storageClassName: my-storage-class0

Resultant PVC:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  annotations:
    pv.kubernetes.io/bind-completed: "yes"
    pv.kubernetes.io/bound-by-controller: "yes"
    volume.beta.kubernetes.io/storage-provisioner: filestore.csi.storage.gke.io
    volume.kubernetes.io/storage-provisioner: filestore.csi.storage.gke.io
  finalizers:
  - kubernetes.io/pvc-protection
  name: my-pvc0
spec:
  accessModes:
  - ReadWriteMany
  resources:
    limits:
      storage: 1Gi
    requests:
      storage: 1Gi
  storageClassName: my-storage-class0
  volumeMode: Filesystem
  volumeName: pvc-XXXXXXXXXXXXXXXXXXXX
status:
  accessModes:
  - ReadWriteMany
  capacity:
    storage: 2560Gi
  phase: Bound

Resultant PV:

apiVersion: v1
kind: PersistentVolume
metadata:
  annotations:
    pv.kubernetes.io/provisioned-by: filestore.csi.storage.gke.io
    volume.kubernetes.io/provisioner-deletion-secret-name: ""
    volume.kubernetes.io/provisioner-deletion-secret-namespace: ""
  finalizers:
  - kubernetes.io/pv-protection
  name: pvc-XXXXXXXXXXXXXXXXXXXX
spec:
  accessModes:
  - ReadWriteMany
  capacity:
    storage: 2560Gi
  claimRef:
    apiVersion: v1
    kind: PersistentVolumeClaim
    name: my-pvc0
  csi:
    driver: filestore.csi.storage.gke.io
    volumeAttributes:
      ip: 10.###.###.###
      storage.kubernetes.io/csiProvisionerIdentity: #####-filestore.csi.storage.gke.io
      volume: vol1
  persistentVolumeReclaimPolicy: Delete
  storageClassName: my-storage-class0
  volumeMode: Filesystem
status:
  phase: Bound

Also, the StorageClass:

allowVolumeExpansion: true
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  annotations:
    components.gke.io/component-name: filestorecsi
    components.gke.io/component-version: 0.10.18
    components.gke.io/layer: addon
  labels:
    addonmanager.kubernetes.io/mode: EnsureExists
    k8s-app: gcp-filestore-csi-driver
  name: my-store-class0
parameters:
  tier: premium
provisioner: filestore.csi.storage.gke.io
reclaimPolicy: Delete
volumeBindingMode: Immediate

I tried the above, and expected the PV and PVC.status capacity to match the original 1Gi requested.