Elastic Compute Cloud
A company is hosting EC2 instances which focus on work-loads for non-production and non-priority batch loads. Also, these processes can be interrupted at any time. What is the best pricing model that can be used for EC2 instances in this case?
A. Reserved instances
B. On-Demand instances
C. Spot instances
D. Regular instances
C. Spot instances
Spot instances enable you to bid on unused EC2 instances, which can lower your Amazon EC2 costs significantly. The hourly price for a Spot instance (of each instance type in each Availability Zone) is set by Amazon EC2, and fluctuates depending on the supply of and demand for Spot instances. Your Spot instance runs whenever your bid exceeds the current market price.
Spot instances are a cost-effective choice if you can be flexible about when your applications run and if your applications can be interrupted. For example, Spot instances are well-suited for data analysis, batch jobs, background processing, and optional tasks.
Option A is invalid because even though Reserved instances can reduce costs, it’s best for workloads that would be active for longer periods of time rather than for batch load processes which could last for a shorter period.
Option B is not right because On-Demand instances tend to be more expensive than Spot Instances.
Option D is invalid because there is no concept of Regular instances in AWS.
For more information on Spot instances, please visit the below URL:
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-spot-instances.html
