AWS EC2 On-Demand is notoriously expensive, and AWS offers many ways to reduce hosting costs. Savings plans are the latest pricing model, which is easiest to get started with and offers a flexible way to save money.
Reserved instance savings, without obligation
The two main savings models that AWS offers – Reserved instances and Spot instances ̵1; both still have their uses. Reserved instances are long-term contracts for specific instances. If you know you will need to run 4
c5.xlargefor more than a year, you can buy an RI contract (and possibly pay a little in advance) to save up to about 60% on hosting costs. If you know your exact needs, you will find the lowest price with RI.
Spot instances are short-term instances used for applications with flexible start and end times. They mainly allow you to buy excessive computing power from AWS at bargain prices. If you run a program that does not care about an interruption of service on one of the machines in a fleet, such as a highly scalable web server workload, you can run your application with these to save as much or even more than reserved instances. Savings plans do not replace these, and if your workload allows it, they can be used together with RI or savings plans to cover nails in application use.
Savings Plan is the new savings model, which was announced in early November. It presents a flexible alternative to reserved instances that do not lock you in a specific instance. AWS already has Convertible RI, which achieves the same impact, but it is clumsy and requires you to sell your agency agreement and buy for another.
Instead of signing a contract with a commitment to use a specific EC2 instance for one year, Sparplan you have signed an agreement that makes a commitment to spend a certain amount of money on EC2. This way, you are not locked into a specific instance or need to manage to change convertible plans – as long as you spend money on EC2, you will save money. Commitment is measured in dollars per hour, so if you spend $ 2
Of course, this is still a commitment, and you still have to spend as much as you commit to. But if you want to switch to another instance, you will be able to without worrying about how it will affect your savings model. The best part is, even if you eventually need twice as much computing power as you planned, you can easily increase
Savings plans have two options – Calculate and EC2. Calculation savings plans are the most flexible and allow you to switch from any EC2 family or region to another. They offer savings “up to 66%”, just like convertible RIs. The calculation also applies to Lambda and Fargate. EC2 savings plans lock you into a specific instance family (e.g.
t3) and region, with the advantage of being slightly cheaper (“up to 72%”). Even if this is more locked in, it’s still better than RI, and you’re free to spin new instances and change instance types while seeing the same savings.
If you plan to use EC2 for at least a year and do not want to lock yourself in a specific instance or manage convertible RIs, there is no reason not to sign up for Compute Saving Plans, especially if half your bill.
How to register
Registering is pretty easy. From the AWS Management Console, open Cost Explorer under Services and select “Buy Savings Plans.”
From here you can select Calculation or EC2 savings plans and the length of the contract period. If you select EC2, you must select the instance family and region.
Then specify how much you plan to use. You can pay everyone in advance, some in advance, or simply stick to the monthly payments. You will be charged each month for the price you specify, regardless of how much you use EC2. You get discounts up to a certain price, and any use beyond that will be charged the usual On-Demand prices. However, you are always free to commit to larger savings plans if your needs change.
If you want to estimate your cost savings, you can use the AWS pricing calculator to do so.