pvc-allow-volume-expansion annotation does not work on PVC's consumed by VMSingle & VLSingle

[syphernl]

We use pvc-autoresizer to automatically increase PVC sizes. This causes .spec.storage.resources.requests.storage in the VictoriaMetrics CR to become out-of-sync with the actual deployed PVC size.
The operator then attempts to resize the PVC back to the configured size but fails.

Example log:

2026-01-26T10:03:56.622481829Z {"level":"info","ts":"2026-01-26T10:03:56Z","logger":"controller.VLSingle","msg":"cannot decrease PVC=vlsingle-victorialogs size from=38Gi to=10Gi, please check VolumeClaimTemplate configuration","vlsingle":"victorialogs","namespace":"victorialogs"}

Current Behavior

According to #867 and https://github.com/VictoriaMetrics/operator/blob/master/config/examples/vmcluster_storage_class_unexpandable.yaml the annotation:

operator.victoriametrics.com/pvc-allow-volume-expansion: "false"

can be set to prevent the operator from decreasing PVC size. The given example is for VMCluster.

I have applied this annotation to the PVC consumed by VMSingle and VLSingle but it appears this does not prevent the operator from attempting to resize.

Expected Behavior

• Annotation operator.victoriametrics.com/pvc-allow-volume-expansion: "false" should also work for PVC's consumed by VMSingle and VLSingle objects.

Notes

• Current behavior leads to unnecessary error logs and potential conflicts with external PVC management.
• Likely this feature is not yet implemented for PVC's consumed by VMSingle and VLSingle.

[AndrewChubatiuk]

currently operator first defines direction of volume size change. if it scales down - operator shows this warning, if it scales up then it checks if annotation is present. maybe it makes sense to change an order of these steps

[syphernl]

FWIW this also causes the following issue:

status:
  observedGeneration: 10
  reason: 'failed create or update vmsingle: cannot create storage: PersistentVolumeClaim
    "vmsingle-victoriametrics" is invalid: spec.resources.requests.storage: Forbidden:
    field can not be less than status.capacity'
  updateStatus: failed

I changed extraArgs on the VMSingle entity but the operator failed/refused to apply until I bumped the .storage.resources.requests.storage to a value at/above the current one.

[AndrewChubatiuk]

hey @syphernl
do you have annotation set directly on PVC or using VMSingle/VLSingle spec.storageMetadata.annotations?

[syphernl]

@AndrewChubatiuk We have this set on VMSingle and VLSingle:

  storageMetadata:
    annotations:
      resize.topolvm.io/enabled: "true"
      resize.topolvm.io/storage_limit: 250Gi
      resize.topolvm.io/threshold: 10%
      resize.topolvm.io/inodes-threshold: 10%
      resize.topolvm.io/increase: 1Gi

[AndrewChubatiuk]

and how do you set operator.victoriametrics.com/pvc-allow-volume-expansion?

[syphernl]

and how do you set operator.victoriametrics.com/pvc-allow-volume-expansion?

We haven't set this particular annotation yet because this is not supported by the currently released operator version

[AndrewChubatiuk]

ah, okay, thought you're observing it in a version built from master

[AndrewChubatiuk]

starting release 0.68.0 with PVC annotation operator.victoriametrics.com/pvc-allow-volume-expansion: false operator should ignore volume size changes if storage was expanded automatically