This document gives an overview of the suspend, stop, or reset operations thatyou can use on a Compute Engine instance. To learn how to perform theseoperations, see instead the following:

• Suspend or resume an instance

• Stop or restart an instance

• Reboot or reset an instance

You can suspend, stop, or reset an instance to do the following:

• Save costs.

• Perform maintenance.

• Troubleshoot issues.

• Free up resources.

You can repeatedly suspend and resume, stop and restart, or reset a runninginstance throughout its lifecycle until the instance is deleted.

Understand instance operations

Based on your workload and cost needs, you can suspend, stop, or reset a computeinstance:

Suspend an instance

When you suspend an instance, this action is similar to closing the lid ofyour laptop. We recommend that you suspend an instance in the followingscenarios:

• You want to save money by no longer paying for the core and memory costsof running an instance, but still pay for storage to preserve its state.

• You don't need the instance at this time, but you want to be able to bringit back up quickly with its OS and application state where you left it.

For more information, seeSuspend operation in thisdocument.

Stop an instance

When you stop an instance, this action is similar to shutting down yourlaptop. We recommend that you stop an instance in the following scenarios:

• You no longer need the instance, but you want to remove and reuse theresources attached to the instance—such as its internal IPaddresses or Google Cloud Hyperdisk volumes.

• You don't need to preserve the guest OS memory, device state, orapplication state.

• You want to change certain properties of the instance and you need to stopthe instance to make these changes.

For more information, seeStop operation in thisdocument.

Reset an instance

When you reset an instance, this action is similar to doing a reset of yourcomputer, such as when you press a reset button or press and hold the powerbutton. A reset operation doesn't perform a graceful reboot, and loss ofunsaved data is possible. We recommend that you reset an instance in thefollowing scenarios:

• You want to re-initialize the instance to its boot state to help ensureoptimal performance and stability.

• You want to resume your workload after your guest OS has crashed and isunresponsive, and you have no other options than resetting the instance.

For more information, seeReset operation in thisdocument.

For an overview of the differences between the stop, suspend, and resetoperations for an instance, see thecomparison table inthis document.

Suspend operation

When you suspend a compute instance, the following occurs:

1. Compute Engine sends anAdvanced Configuration and Power Interface (ACPI) G1 Sleeping signalto the guest OS and changes the instance state toSUSPENDING. Then,Compute Engine uses persistent storage to store the following:

   • The guest OS memory

   • The device state

   • The application state of the instance

   The storing operation might take some time to complete, depending on theamount of data to store.

2. After Compute Engine has completed storing the data, the instancestate transitions toSUSPENDED within a few seconds, and the suspendoperation completes. All resources attached to the instance, like disks andstatic IP addresses, remain attached to the instance. However, any ephemeralIP addresses are released unless you promote them to a static IP address.

Unless youresumeordelete the instance, theinstance remains in theSUSPENDED state for up to 60 days. After that time,Compute Engine transitions the instance state toTERMINATED, and theinstance loses the preserved guest OS memory, device state, and applicationstate.

Stop operation

When you stop or delete a compute instance, or Compute Engine does sofor a scheduled stop or deletion, the following occurs:

1. Ifgraceful shutdown isenabled, then the instance enters thePENDING_STOP state, giving you timeto finish running tasks before the shutdown process begins. The instanceremains in this state until the graceful shutdown process times out or youmanually end it.

2. Compute Engine sends theACPI G2 Soft Off signalto the guest OS in the instance, and then sets the instance state toSTOPPING. Unless you specified toskip the guest OS shutdown,the time that the guest OS has to cleanly shut down depends on the instancetype as follows:

   • Spot VMs: for Spot VMs and preemptibleinstances, the guest OS shuts down in a maximum of 30 seconds. Thisperiod is the same length as thepreemption process.

   • Other instance types: for any other instance types,Compute Engine gives the guest OS up to a maximum of 120 secondsto shut down.

   Caution: If a shutdown script is still running at the end of the allowedguest OS shutdown period, then Compute Engine forcefully stops it.If you're concerned that a shutdown script may not finish on time, then tohelp ensure that the guest OS shuts down only after all shutdown scriptshave finished running,stop an instance from the guest OS.

3. After the guest OS has shut down, Compute Engine sends the ACPI G3Mechanical Off signal to instance, and, depending on the operation that isrunning, does one of the following:

   • For stop operations: Compute Engine sets the instance statetoTERMINATED within a few seconds, and the stop operation completes.The instance retains its attached resources, configuration settings,internal IP addresses, MAC addresses, and metadata.

   • For delete operations: Compute Engine deletes the instanceand all attached resources within a few seconds.

Reset operation

When you reset a compute instance, Compute Engine immediately restartsthe instance without sending an ACPI shutdown signal to the guest OS, bypassingany shutdown procedure. When your reset an instance, Compute Engine doesthe following:

• Compute Engine re-initializes the instance to its initial bootstate, but doesn't modify instance metadata or attached disks.

• Compute Engine wipes the contents of the instance's memory.

• Compute Engine keeps the instance state toRUNNING throughout thereset operation.

The reset operation doesn't change any instance properties. The instance retainsits ephemeral IPs, static external IPs, attached disks, machine type, and LocalSSD disks (if any).

Warning: Only reset an instance as a last resort when the guest OS has crashedand is unresponsive. This action forces an abrupt shutdown of the guest OS,which can cause data loss or file system corruption. To cleanly restart aninstance, see insteadReboot the instance.

Comparison table

The following table shows how stop, suspend, and reset operations affect acompute instance and its attached resources:

	Suspend an instance	Stop an instance	Reset an instance
Billing	While an instance is in theSUSPENDING orSUSPENDED state, you don't incur charges for CPU usage. However, you keep incurring charges for the resources attached to the instance until you delete them.	While an instance is in theSTOPPING orTERMINATED state, you don't incur charges for CPU usage. However, you keep incurring charges for the resources attached to the instance until you delete them.	Because the instance remains in theRUNNING state when it's resetting, you keep incurring charges for the instance at the same rate as a running instance.
Instance state	SUSPENDED	TERMINATED	RUNNING
Attached disks	Attached disks are maintained and you keep incurring charges for them.	Attached disks are maintained and you keep incurring charges for them.	Attached disks are maintained and you keep incurring charges for them.
Memory and instance state	The guest OS and application state are preserved and restored when the instance is resumed. You incur charges at a specific rate for storing the preserved data. For more information, see thepricing for suspended instances.	The instance resets to power-on state and no data is saved.	The instance resets to power-on state and no data is saved.
GPUs	Not supported. If a GPU is attached to an instance, then you can't suspend the instance.	You don't incur charges for GPUs when an instance is stopped. A GPU that is attached to an instance with aTERMINATED state doesn't count against your project quota.	You incur charges at standard GPU prices.
Local SSD disks	When you suspend an instance, you can choose whether to discard or preserve the data on the attached Local SSD disks. If you opt topreserve Local SSD data (Preview), then Compute Engine migrates the Local SSD data to durable storage, and you incur charges for the used storage space until you resume or delete the instance.	When you stop an instance, you can choose whether to discard or preserve the data on the attached Local SSD disks. If you opt topreserve Local SSD data (Preview), then Compute Engine migrates the Local SSD data to durable storage, and you incur charges for the used storage space until you restart or delete the instance.	Local SSD disks and their data are maintained; however, resetting an instance can cause data loss or corrupt file systems.
External ephemeral IP addresses	Compute Engine releases ephemeral IP addresses when an instance is suspended, and it assigns a new ephemeral IP address to the instance when the instance resumes. To retain an external IP address, promote it to a static IP address.	Compute Engine releases ephemeral IP addresses when an instance is stopped, and it assigns a new ephemeral IP address to the instance when the instance restarts. To retain an external IP address, promote it to a static IP address.	Ephemeral IP addresses are maintained.
External static IP addresses	Static external IP addresses are maintained. If you reserve a static external IP address and don't assign it to an instance, then you're charged at a higher rate than for static and ephemeral external IP addresses that are in use. For more information, seeExternal IP address pricing.	Static external IP addresses are maintained. If you reserve a static external IP address and don't assign it to an instance, or you assign it an instance in theTERMINATED state, then you're charged at a higher rate than for static and ephemeral external IP addresses that are in use. For more information, seeExternal IP address pricing.	Static external IP addresses are maintained.
Internal IP or MAC addresses	Internal IP and MAC addresses are maintained.	Internal IP and MAC addresses are maintained.	Internal IP and MAC addresses are maintained.
VM metadata	VM metadata is maintained.	VM metadata is maintained.	VM metadata is maintained.

Pricing

The following sections outlines the pricing for stop, suspend, or resetoperations for a compute instance.

Pricing for suspending an instance

After a compute instance state transitions toSUSPENDING, you no longer incurcharges for CPU usage. However, you continue incurring charges for the followingresources attached to the instance until you delete them:

• The instance's memory.

• Any disks attached attached to the instance.

• Any static IP addresses assigned to the instance.

Additionally, you might still incur charges for your software license fees. Forexample, if you suspend Windows Server instances, you don't incur charges forWindows Server license fees. However, you might still incur charges for othertypes of licenses.

For more information, see thepricing for suspended instances.

Pricing for stopping an instance

After a compute instance state transitions toSTOPPING, you no longer incurcharges for CPU usage. However, you continue incurring charges for any resourcesattached to the instance, such as disks and external IP addresses, until youdelete them.

For more information, seeInstance uptime.

Pricing for resetting an instance

Since the state of a compute instance remainsRUNNING when you reset it, youcontinue to incur charges for the instance at the same rate as a runninginstance.

For more information, seeVM instance pricing.

What's next

• Suspend or resume an instance

• Stop or restart an instance

• Schedule an instance to start and stop

• Limit the runtime of an instance

• Reboot or reset an instance