Amazon EC2: Spot Instances

[jorgearj]

How can we address Spot Instances (http://aws.amazon.com/ec2/pricing/#spot)?

One way would be to ignore the price fluctuation and use the table from the website.

Other way (probably the most accurate) could be to use a Usage Variable instead of a constant for the price, then this usage variable could be set to whatever value is the current spot instance value.

Finally we could leave this issue to the providers by enforcing that when a user asks for the spot instances price the model is generated with the current price.

This could lead to the need for a new property requestForQuote.

[jorgearj]

a mechanism for validate the price model might be needed.
For example, to know if the current model is valid in a particular time.
Spot Instances may change every minute os so.