Stopped Vertex AI Workbench instances that still bill for their disks
What does ZopNight detect here?
A stopped Vertex AI Workbench instance has no CPU or GPU charges, but Google still bills its boot and data disks. ZopNight flags Workbench instances in the `STOPPED` state and reports their billed cost, which at that point is disk storage, as the saving from deleting them. It stays silent when the cost is unknown.
Signal and threshold
| Field | Value |
|---|---|
| Rule IDs | RC-1213 |
| Category | orphan |
| Severity | low |
| Metric | none — pure configuration read |
| Threshold | state STOPPED |
| Source | ZopNight |
| Permissions used | notebooks.instances.list · notebooks.instances.get |
Where it applies
A shut-down notebook is a disk bill
Vertex AI Workbench instances are Compute Engine VMs with JupyterLab on top. Google’s idle shutdown page spells out the billing: while an instance is shut down “there are no CPU or GPU usage charges”, but “disk storage charges still apply”. The boot disk and the data disk, often sized generously for datasets, keep charging every hour the instance sits stopped.
Workbench shuts instances down after 180 idle minutes by default, so stopped notebooks pile up naturally. Most get restarted. Some never do.
Listing stopped Workbench instances
Workbench instances are zonal. List the stopped ones in a zone:
gcloud workbench instances list --location=us-central1-a --filter="state=STOPPED"Check the owner label and the last activity date in the console before assuming one is abandoned.
When a notebook counts as stopped
ZopNight reads the instance state and fires only when it resolves to STOPPED. Any other state,
or a state it cannot read, produces nothing. There is no dwell time: a notebook stopped
yesterday is flagged just like one stopped months ago, so treat the list as a review queue.
What keeps a stopped notebook off the list
The rule needs a billed cost for the instance. If that cost is unknown or zero, ZopNight raises nothing rather than reporting a $0 saving. Running notebooks without idle shutdown are a different problem, covered by GCP Vertex AI Workbench Notebook Missing Idle Shutdown.
The disk cost you stop paying
saving = billed monthly cost of the stopped instance (its disks)cost after fix = 0Because compute is already off, the full remaining cost goes away only when the instance and its disks are deleted. The finding is labelled as a cleanup, and it ships even when the amount is small.
Deleting a notebook you no longer need
- Ask the owner whether the notebook holds unsaved work. Start it if needed and copy notebooks and data to a Cloud Storage bucket or a Git repository.
- Delete the instance:
gcloud workbench instances delete INSTANCE_NAME --location=us-central1-a. - Confirm in the Compute Engine disks list that no data disk was left behind.