Suspend/resume has been made widely available by Google. These capabilities allow you more control over how much Google Cloud resources you use. Suspending a Google Compute Engine VM saves the state of the instance to disk, allowing you to resume it later from where you left off. You don’t pay for cores or RAM when your instance is in the SUSPENDED state; instead, you just pay for the storage expenses of your instance memory. Other VM operating costs, such as OS licensing, could be decreased as well.
How does it work?
Suspending an instance sends an ACPI S3 signal to the instance’s operating system, which has two key advantages over other cloud providers’ similar functionality.
- Compatibility with a wide range of OS images without the need for a cloud-specific OS image or the installation of daemons. Suspend may operate with undocumented and modified OS images that react to the ACPI S3 signal.
- When Suspend is requested, storage is dynamically supplied and is independent from the instance’s boot disk. This is in contrast to other cloud implementations, which need you to guarantee that you have enough available space on your boot drive to save the instance state, potentially increasing your VM’s running costs. This also guarantees that your suspended instance just uses the storage space that it requires.
