AWS, Google and Azure are in a price war; and seem committed to matching on-demand prices. That is good, but not the whole story.
The under reported price is that of the AWS spot market; which can be up to 10 x cheaper than on-demand prices.
On-demand / month
Spot / month
There are only 2 differences between AWS spot and on-demand instances.
1. Spot instances take longer to start (5 min vs 1 min)
2. Spot instances “fail” more frequently; when spot prices move above your bid price your instance gets terminated.
You might think that ( 2 ) would prevent you from using spot to host “always on” services like Cloud Foundry.