Run your low-CPU workloads more cost-effectively with burstable VMs

Small workloads, such as web servers, microservices, continuous integration-continuous deployment (CICD) pipelines, development, and test environments, often use regular virtual machines (VMs) that are provisioned with more CPU resources than needed. These workloads typically have low CPU utilization and occasionally need to use more CPU when incoming traffic or application requests spike. Burstable VMs enable your workloads to use a fraction of the CPU with the ability to burst to 100% of the CPU for short periods of time, at a lower cost than regular VMs.

As part of our overall goal of making more flexible infrastructure, you can now run low-CPU workloads cost-effectively on Oracle Cloud Infrastructure (OCI) using burstable VMs.

^{Figure 1: Typically low CPU utilization with occasional burst in CPU}

What are burstable VMs?

With a flexible VM, you can choose the number of CPU cores and memory to best suit your workload. In these VMs, you can use 100% of the CPU core all the time. This capability is ideal for workloads that consistently need the full power of the CPU core. For workloads that need a small amount of CPU most of the time but occasionally need a higher amount of CPU, burstable VMs now offer you a more cost-effective option with the additional flexibility of choosing the fraction of CPU needed.

With a burstable VM, you can select the OCPU between 1–64 cores, the memory between 1–64 GB per core (up to a maximum of 768 GB), and the baseline OCPU utilization as 12.5% or 50% of the total OCPUs. The baseline determines the minimum fraction of the CPU resources always available to the VM. A burstable VM with one OCPU and a 12.5% baseline can run at a sustained CPU performance of 12.5% of one core, or it can run lower than 12.5% and occasionally burst up to 100% of the core for short periods of time.

We wanted to keep burstable VM pricing simple, so burstable VMs are charged at our standard OCPU per hour price but only for the baseline OCPU chosen. This ensures that burstable VMs are much cheaper than non-burstable VMs. For a one-core, 12.5% baseline VM, you’re charged for 0.125 OCPU each hour, whether you use 12.5% or less of the CPU core or if you burst and use 100% of the core.

Burstable VM's flexibility and simple pricing make it a great choice to run your low CPU workloads. For more information on burstable VMs, see the documentation.

How do I get started?

You can easily get started with burstable VMs. Suppose you have a small workload like a webserver whose average CPU usage is less than 10% of a core. Now, instead of launching a regular VM with one core, you can configure a burstable VM with a baseline of 12.5% of a core to better optimize for this workload.

Using the Console, when creating an instance, choose the AMD shape series, and then select VM.Standard.E3.Flex as the shape. When configuring the shape, select the number of OCPU as 1, select the Burstable option. Finally choose the baseline utilization per OCPU as 12.5%. This configuration ensures that you have a baseline CPU performance of at least 12.5% of one core. And that’s it!

^{Figure 2: Configure burstable VM}

Learn more about burstable VMs

Burstable VMs are available with the AMD EPYC E3-based flexible instances, running on Linux and Windows operating systems. We plan to enable this feature on other flexible VM instance types in the future, so stay tuned for more updates. For more information, see the documentation about burstable VMs.

You can try out burstable VMs and other Oracle Cloud Infrastructure services by signing up for a trial account with $300 in credits.