GCP Spot VM: Introduction and how to use them?

Google Cloud platform has recently launched Spot Virtual machines (VM). These Spot VMs aim to capitalize on the excess compute capacity of the Google Cloud platform on a cost-efficient basis. The Spot VMs allow the Google Cloud Platform to enhance its current Preemptible VMs by offering a cheaper alternative, with lesser restrictions and more flexibility.

The GCP equivalent of AWS and Azure Spot instances are Spot VMs. This article will discuss Spot VMs and how you can use Spot VMs to reduce your compute engine costs.

What are GCP Spot VMs?

GCP Spot VMs provide an affordable way to run jobs on demand. Spot VMs are a combination of on-demand and preemptible VMs and are cheaper than on-demand VMs. With the help of a Spot VM, users can capitalize on the excess compute capacity of the Google Cloud platform on a cost-efficient basis. However, these instances can be re-allocated by the Google Cloud Platform at any time if they need to be used somewhere else.

GCP Spot Instances currently offer the same machine types as on-demand VMs. We can use Spot VMs with fault-tolerant workloads because of the temporary nature of the instances. Internally the Google Kubernetes Engine (GKE) will make Compute Engine Spot VMs behave like a managed instance group.

What is the difference between a Spot VM and a Preemptible VM?

Currently, the Preemptible VM can be terminated on or before 24 hours of its creation. The Spot VM, on the other hand, has no such restriction. However, both the VMs are still on-demand and can be re-allocated by the Google Cloud Platform at any time.

GCP Spot VMs are equivalent to the Amazon Web Services (AWS) EC2 Spot instances that run on the excess compute capacity of AWS. GCP ver, GCP’s per-minute granularity makes it an enticing offer for potential users. It allows the Spot VMs to be efficiently used for workloads that have low resource demands.

What is the pricing model for Spot VM?

GCP Spot pricing makes it a lucrative choice for users to run workloads at a radically reduced rate. Preemptible VMs come at a 79% predicatble discount compared to on-demand VMs. Spot VMs, on the other hand, comes at a saving of variable 60%-91% discount compared to on-demand VMs. Spot VMs also provide additional benefits, like automated workload scheduling, cluster autoscaler, and more.

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Conclusion

Spot VMs have some limitations. If you are using Google Cloud free tier, you won’t be able to use Spot VMs. Spot VMs are also excluded from Compute Engine Service Level Agreement (SLA) and cannot be used for live migration. As discussed above, the resources can be re-allocated at any time and hence are finitely available.