I recently went through a sizing exercise with one of our customers and thought it might be useful for some of our other government cloud customers. This on-premises environment customer was looking to move their Oracle applications to Oracle Government Cloud. When in doubt of which sizing method to use, consult your Oracle Enterprise Cloud Architect.
(OCPU) and a virtual CPU (vCPU). Oracle uses an OCPU, and other cloud service providers use a vCPU. What’s the difference? One OCPU has one physical core with two threads, the same in two vCPUs. With Oracle, you get an entire physical core.
With Oracle Government Cloud, you’re moving into a home with two floors all to yourself. With other cloud service providers, you’re also moving into a home with two floors, except you share the kitchen, bathroom, washer, and dryer. This analogy helps you understand sizing environments for Oracle Government Cloud and realizing what kind of performance you receive.
You have two options to size and determine the right shape for your workloads. The first way is the easy way: take the total vCPUs of all your workloads and convert them into OCPUs. Take the total vCPUs and divide by two, which gives you the total OCPUs you need. (Remember, one OCPU = two vCPU = two threads.) You can stop here if you want. You now have an idea of how many OCPUs you require and a general idea of costs for running these workloads in the Oracle Government Cloud.
The second way is to review the workloads with a fine-tooth comb. This method involves looking at each virtual machine (VM) and matching it with an Oracle Government Cloud shape. This method can get tricky and, sometimes, your VM sizes won’t match the shapes in Oracle Government Cloud perfectly. You can end up with less OCPU or more OCPU, depending on the workload.
I reminded the customer not to worry about RAM. You most likely get more RAM than needed, which is a good thing. The customer’s environment was small enough to review. In three out of the 20 workloads, the VM size didn’t match the Oracle Government Cloud shape. Here, you can save on costs.
We noticed that some shapes were about two OCPUs off. Going to the next larger shape gave the shape too many resources, which led to a higher cost. The next lower shape gave them not enough resources. Oracle Government Cloud has its advantages because we don’t oversubscribe, and we provide two threads per OCPU. With Government Cloud, you receive better performance than you previously had. Evaluate on a workload by workload basis. The customer determined that with the shape assigned, the workloads had enough resources to operate.
If you need to have perfectly matching shapes or have workloads that require extra threads, you can use our AMD EPYC E3 series flexible shapes, where you can adjust the shape size to the exact OCPU and RAM required.
You’re not locked in by shape size. If you need to change the shape size, you can always do that later. Shut down your instance, change the shape, and restart the instance.
When sized right, moving to the cloud can result in cost savings. As seen with the customer, adjusting to OCPUs here and there can lead to cost savings. To optimize cost savings and have a better total cost of ownership (TCO) than your on-premises environment, keep the following concepts in mind:
Analyze usage data: When sizing, you can provide an inventory dump from your hypervisor, a table containing resources allocated to each VM. In these cases, you most likely allocate more resources than needed. If the table includes a column that describes what’s being consumed, you have more information for better decision making about the need for a larger or smaller shape. Such data helps in saving costs. Continue to monitor your instances post-deployment to adjust as needed.
Performance need: If you don’t monitor your VMs frequently, we suggest running a performance analysis tool throughout peak usage. This analysis gives you the actual consumed data, so you can optimize your costs: not so much that you go over budget and not so little that you’re compromising on performance.
Compute processing power: Many customers view computing power from a processor frequency point of view, an on-premises habit. Oracle’s Government Cloud VM Standard 2 shape uses Intel Xeon Platinum 8167M with a base frequency of 2.0 GHz and a max turbo frequency of 2.4 GHz. This option is better than most on-premises environments have in the servers. However, by the time you perform these calculations, there’s a new and faster processor available. If you need more compute processing power, see our specialty shapes that include GPUs for high-performance computing (HPC).
Start small: When in doubt, start with a smaller OCPU shape. Unless you’re sure that you need all the CPUs or need the RAM, go with less OCPU to start. You’re getting the entire core and two threads—no sharing. That’s where Oracle Government Cloud has its advantages. Typically, with on-premises or type 1 hypervisors, as with the customer, they used a four-to-one vCPU to physical core ratio, assuming an oversubscription ratio of four. Oracle Government Cloud has no oversubscription. You get the entire core and two threads. If you go with a larger shape every time, you end up spending way more than you need. Start small and increase as needed.
Not all environments need equal resources: Customers also want the same resources across disaster recovery, development, and testing environments. They’re afraid of running out of hardware and an on-premises mentality. If you have a development or testing environment, it doesn’t have to use the same shapes as your production. You can use smaller shapes to start and change shapes later. If your development and testing environment need to run all the time, keep the shapes small and increase when you ramp up development and testing.
You no longer need to ask for everything upfront with the cloud. The resources are always there. Ask for what you consume and adjust accordingly. Throw out the 80–20 rule, where you need a 20% buffer of on-premises resources available to not overtax your on-premises hardware.
We know that every use case is different. The only way to know if Oracle Cloud Infrastructure is right for you is to try it. You can select either the Oracle Cloud Free Tier or a 30-day free trial in our commercial regions, which includes US$300 in credits to get you started with a range of services, including compute, storage, and networking. The Oracle Cloud Infrastructure regions dedicated to the Government consist of FedRAMP high federal and civilian authorized regions and IL5 Department of Defense (DoD) authorized regions. If you prefer Oracle Government Cloud, consult your Oracle sales representative for a proof of concept in the appropriate region.